Neoplasia — MCQs

A 58-year-old woman with colon cancer presents with 3 months of increasing shortness of breath. A chest X-ray reveals numerous, bilateral, round masses in both lungs. Histologic examination of an open-lung biopsy discloses malignant gland-like structures, which are nearly identical to the colon primary. Which of the following changes in cell behavior was the first step in the process leading to tumor metastasis from the colon to the lung in this patient?

Q347Medium

Defective DNA repair is seen in all of the following conditions EXCEPT?

Q348Easy

Post-transplant lymphoma occurs due to proliferation of which of the following cells?

Q349Easy

Apoptosis is inhibited by which of the following?

Q350Easy

Gleason's score is used for?

Neoplasia Indian Medical PG Practice Questions and MCQs

Question 341: Malignancy is typically associated with disordered differentiation and maturation. Which of the following best describes anaplasia?

A. Hepatic tumors synthesizing bile
B. Skin tumor producing keratin pearl
C. Bronchial epithelium cells producing keratin pearl (Correct Answer)
D. Colonic tumor cell producing mucin

Explanation: **Explanation:** **Anaplasia** literally means "to form backward." It refers to a lack of differentiation, where tumor cells lose the structural and functional characteristics of their tissue of origin [1]. The hallmark of malignancy is the degree to which cells fail to resemble their normal counterparts. **Why Option C is Correct:** The bronchial lining is normally composed of pseudostratified ciliated columnar epithelium. If a bronchial tumor produces **keratin pearls**, it indicates that the cells have not only become malignant but have undergone **squamous metaplasia** followed by neoplastic transformation [2]. The production of keratin (a squamous feature) by cells originating from a columnar lineage is a classic example of disordered differentiation and morphological deviation from the parent tissue, characteristic of anaplastic changes in squamous cell carcinoma of the lung. **Analysis of Incorrect Options:** * **Options A, B, and D:** These represent **well-differentiated** tumors. In these cases, the malignant cells retain the functional capabilities of their cells of origin (Hepatocytes making bile, Squamous cells making keratin, Colonic cells making mucin) [1]. While these are malignant, they show minimal anaplasia because they still "mimic" their home tissue. **NEET-PG High-Yield Pearls:** 1. **Morphological Hallmarks of Anaplasia:** Pleomorphism (variation in size/shape), Hyperchromatism (dark nuclei), increased Nuclear-to-Cytoplasmic (N:C) ratio (approaching 1:1), and atypical tripolar or quadripolar mitotic figures [1]. 2. **Polarity:** Anaplastic cells show a complete loss of organized growth patterns (loss of polarity). 3. **Correlation:** The degree of anaplasia determines the **Grade** of the tumor; the more anaplastic a tumor, the higher the grade and the more aggressive the clinical behavior. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 276-278. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 278-280.

Question 342: All of the following genes are implicated in colon carcinoma by the classical pathway except?

A. APC
B. K-ras
C. Beta-catenin
D. Mismatch repair genes (Correct Answer)

Explanation: **Explanation:** Colorectal carcinoma (CRC) primarily develops through two distinct molecular pathways: the **Classical (Adenoma-Carcinoma) Pathway** and the **Microsatellite Instability (MSI) Pathway** [4]. **Why Mismatch Repair (MMR) genes is the correct answer:** Mismatch repair genes (such as *MLH1, MSH2, MSH6,* and *PMS2*) are the hallmark of the **MSI Pathway**, not the classical pathway [3]. Deficits in these genes lead to the accumulation of mutations in microsatellite repeats. This pathway is associated with **Lynch Syndrome** (Hereditary Non-Polyposis Colorectal Cancer) and "serrated" pathway lesions [4]. **Analysis of Incorrect Options (Classical Pathway Components):** The Classical Pathway (Chromosomal Instability Pathway) accounts for 80% of sporadic CRCs and follows a predictable sequence of mutations: * **APC (Option A):** Known as the "gatekeeper" of colonic neoplasia. Loss of the *APC* gene is the earliest event, leading to the formation of small adenomas [2]. * **Beta-catenin (Option C):** In the absence of *APC* function, beta-catenin accumulates and translocates to the nucleus, where it activates genes promoting cell proliferation (e.g., *MYC*, *Cyclin D1*) [1]. * **K-ras (Option B):** Mutations in *K-ras* occur after *APC* loss, promoting the growth of the adenoma and increasing its size and complexity [1]. **High-Yield NEET-PG Pearls:** * **Sequence of Classical Pathway:** *APC* loss (Gatekeeper) → *K-ras* mutation (Growth) → *p53/DCC* loss (Transformation). * **Lynch Syndrome:** Characterized by right-sided (proximal) colon cancers and associated with MMR gene mutations [3]. * **FAP (Familial Adenomatous Polyposis):** Caused by germline mutations in the *APC* gene on chromosome **5q21** [4]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, p. 819. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 304-305. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 819-821. [4] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 821-822.

Question 343: A man presents with cervical adenopathy. What is the most likely diagnosis?

A. Arteriovenous malformation
B. Cellulitis
C. Graves' disease
D. Lymphoma (Correct Answer)

Explanation: **Explanation:** **Correct Answer: D. Lymphoma** The term **cervical adenopathy** refers to the enlargement of the cervical lymph nodes [1]. In the context of pathology and clinical medicine, persistent or significant lymphadenopathy is a hallmark presentation of **Lymphoma** (both Hodgkin and Non-Hodgkin) [1], [2]. Lymphomas typically present as painless, rubbery, and firm lymph node enlargements [2]. In a clinical exam setting, when a patient presents with an isolated or generalized neck mass that is identified as "adenopathy," a neoplastic process involving the lymphoid tissue is the most likely diagnosis among the provided choices [1]. **Why the other options are incorrect:** * **A. Arteriovenous malformation (AVM):** This is a vascular structural abnormality. While it can cause a neck mass, it would present with a thrill or bruit and is not characterized as "adenopathy" (which specifically refers to glandular/node enlargement). * **B. Cellulitis:** This is a spreading bacterial infection of the deep dermis and subcutaneous tissues. It presents with localized erythema, warmth, and pain, rather than discrete lymph node enlargement. * **C. Graves' disease:** This involves diffuse enlargement of the **thyroid gland** (goiter) due to autoimmune stimulation, not the lymph nodes. **NEET-PG High-Yield Pearls:** * **Rule of 80s for Neck Masses:** In adults, 80% of non-thyroid neck masses are neoplastic; of those, 80% are malignant. * **Virchow’s Node:** A specific type of supraclavicular adenopathy (usually left-sided) indicating metastatic abdominal malignancy (e.g., Gastric Adenocarcinoma). * **Painful vs. Painless:** Painful nodes usually suggest an inflammatory/infectious process (lymphadenitis), while painless, fixed nodes are highly suspicious for malignancy (Lymphoma or Metastasis) [2]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 549-551. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, p. 618.

Question 344: Which of the following tumors is associated with BRAF mutation?

A. Adenocarcinoma of the colon (Correct Answer)
B. Medullary thyroid carcinoma
C. Hodgkin's lymphoma
D. Hepatocellular carcinoma

Explanation: **Explanation:** **BRAF mutations** (specifically the V600E mutation) are critical drivers in the MAP-kinase pathway. In **Adenocarcinoma of the colon**, BRAF mutations are characteristically associated with the **Serrated Pathway** of carcinogenesis. These tumors often arise from sessile serrated adenomas, exhibit **Microsatellite Instability (MSI-H)** due to CpG island methylator phenotype (CIMP), and are typically located in the right (proximal) colon [1]. **Analysis of Options:** * **A. Adenocarcinoma of the colon (Correct):** Approximately 10-15% of sporadic colorectal cancers harbor BRAF mutations. They serve as a poor prognostic marker but are a hallmark of the sporadic MSI pathway [2]. * **B. Medullary Thyroid Carcinoma (Incorrect):** This tumor is classically associated with **RET proto-oncogene** mutations (MEN 2A/2B). Note: BRAF is the most common mutation in *Papillary* thyroid carcinoma, not Medullary. * **C. Hodgkin’s Lymphoma (Incorrect):** This is associated with EBV infection and NF-̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀ဃB activation. BRAF mutations are rare here but are pathognomonic for **Hairy Cell Leukemia**. * **D. Hepatocellular Carcinoma (Incorrect):** Common drivers include **TP53** and **CTNNB1** (̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀̀́00%] HBV/HCV or cirrhosis. **NEET-PG High-Yield Pearls:** * **BRAF V600E** is also a key marker for **Malignant Melanoma**, **Papillary Thyroid Carcinoma**, and **Hairy Cell Leukemia** (100% association). * In Colorectal Cancer, BRAF and KRAS mutations are usually **mutually exclusive** [1]. * The presence of a BRAF mutation in an MSI-high colorectal tumor suggests a **sporadic** origin rather than Lynch Syndrome (HNPCC).", "inlineCitations": [ { "referenceNumber": 1, "supportedClaim": "In colon adenocarcinoma, BRAF mutations are associated with the serrated pathway, MSI-high status, and right-sided tumor location, and are typically mutually exclusive with KRAS mutations." }, { "referenceNumber": 2, "supportedClaim": "Approximately 10-15% of sporadic colorectal cancers harbor BRAF mutations, which are characteristic of the sporadic microsatellite instability pathway." } ], "bibliography": [ { "referenceNumber": 1, "citation": "Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 819-821.", "relevanceScore": 9, "relevanceReason": "Directly explains the molecular pathways of colon adenocarcinoma, specifically mentioning MSI, right-sidedness, and the role of BRAF/KRAS mutations." }, { "referenceNumber": 2, "citation": "Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 373-374.", "relevanceScore": 8, "relevanceReason": "Confirms the prevalence (15%) of high microsatellite instability in sporadic colon cancers, which the explanation links to BRAF mutations." } ], "skippedReferences": [ { "referenceNumber": 3, "reason": "too_general", "explanation": "Focuses on Lynch Syndrome (HNPCC) and FAP rather than the specific BRAF mutation requested by the question." }, { "referenceNumber": 4, "reason": "duplicate_information", "explanation": "Contains similar information to Reference 2 regarding the percentage of sporadic MSI-high tumors but is less specific regarding molecular drivers." }, { "referenceNumber": 5, "reason": "too_general", "explanation": "Discusses the adenoma-carcinoma sequence generally and chromosomal loci, but does not provide specific details on BRAF mutations." } ], "processingNotes": { "referencesProvided": 5, "referencesUsed": 2, "referencesSkipped": 3 } }``` **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 819-821. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 373-374.

Question 345: Which of the following is true regarding sarcomas?

A. Malignant tumors of mesenchymal origin (Correct Answer)
B. Usually spread by vascular invasion
C. Frequently metastasize to regional lymph nodes
D. Are only loosely invasive

Explanation: **Explanation:** **1. Why Option A is correct:** Sarcomas are defined as malignant neoplasms arising from **mesenchymal (connective) tissues** [1]. This includes structures derived from the mesoderm, such as bone, cartilage, fat, muscle, and blood vessels. In contrast, "carcinomas" arise from epithelial cells [1]. **2. Why other options are incorrect:** * **Option B (Vascular Invasion):** While it is true that sarcomas characteristically spread via the **hematogenous (bloodborne) route** [2], this option is technically "less correct" than the fundamental definition provided in Option A. In the context of NEET-PG, the histological origin is the primary defining feature. * **Option C (Lymph Node Metastasis):** This is generally **false**. Carcinomas typically spread via lymphatics, whereas sarcomas rarely involve lymph nodes [2]. * **Option D (Loosely Invasive):** Sarcomas are **highly aggressive and locally invasive** [3]. They often lack a true capsule (or possess a "pseudocapsule") and infiltrate surrounding tissues extensively, making surgical resection challenging. **High-Yield Clinical Pearls for NEET-PG:** * **The "Rule of Exceptions":** While most sarcomas spread hematogenously, a few frequently metastasize to **lymph nodes**. Remember the mnemonic **SCARE**: **S**ynovial sarcoma, **C**lear cell sarcoma, **A**ngiosarcoma, **R**habdomyosarcoma, and **E**pithelioid sarcoma. * **Most common site of metastasis:** For most sarcomas, the **lungs** are the first and most common site of distant spread [2]. * **Nomenclature:** A benign mesenchymal tumor ends in "-oma" (e.g., Lipoma), while the malignant counterpart ends in "-sarcoma" (e.g., Liposarcoma) [1]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 208-209. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, p. 282. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, pp. 1224-1225.

Question 346: A 58-year-old woman with colon cancer presents with 3 months of increasing shortness of breath. A chest X-ray reveals numerous, bilateral, round masses in both lungs. Histologic examination of an open-lung biopsy discloses malignant gland-like structures, which are nearly identical to the colon primary. Which of the following changes in cell behavior was the first step in the process leading to tumor metastasis from the colon to the lung in this patient?

A. Arrest within the circulating blood or lymph
B. Exit from the circulation into a new tissue
C. Invasion of the underlying basement membrane (Correct Answer)
D. Penetration of vascular or lymphatic channels

Explanation: **Explanation:** The metastatic cascade is a highly organized, multi-step process. For a primary epithelial tumor (like colon adenocarcinoma) to metastasize, it must first break away from the primary site [1]. **1. Why the correct answer (C) is right:** The **first step** in the metastatic process is the **invasion of the extracellular matrix (ECM)**. For epithelial cells, this begins with the loss of intercellular adhesions (e.g., downregulation of E-cadherin) followed by the **invasion of the underlying basement membrane** [1, 2]. This is achieved through the secretion of proteolytic enzymes like Matrix Metalloproteinases (MMPs) and Cathepsin D [1, 2]. Without breaching the basement membrane, a tumor remains *in situ* and cannot access the underlying stroma or vessels. **2. Why the incorrect options are wrong:** * **D. Penetration of vascular or lymphatic channels:** This is known as *intravasation*. It occurs only *after* the tumor cells have traversed the basement membrane and migrated through the interstitial connective tissue [2]. * **A. Arrest within the circulating blood or lymph:** This occurs much later in the cascade. Once in the circulation, tumor cells must survive immune surveillance (often by forming tumor-platelet emboli) before lodging in a distant capillary bed [2]. * **B. Exit from the circulation into a new tissue:** This is known as *extravasation*. It is one of the final steps before the formation of a secondary metastatic deposit (colonization) [2]. **Clinical Pearls for NEET-PG:** * **E-cadherin:** The "glue" of epithelial cells. Loss of E-cadherin is a hallmark of the **Epithelial-Mesenchymal Transition (EMT)**. * **MMPs (especially MMP-2 and MMP-9):** These are Type IV collagenases that degrade the basement membrane [1, 3]. * **"Cannonball Metastasis":** The bilateral, well-circumscribed lung masses described in the question are classic for hematogenous spread from primary sites like the colon, kidney (RCC), or breast. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 314-315. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 233-234. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 232-233.

Question 347: Defective DNA repair is seen in all of the following conditions EXCEPT?

A. Xeroderma pigmentosum
B. Werner syndrome
C. Bloom syndrome
D. Friedreich's ataxia (Correct Answer)

Explanation: **Explanation:** The core concept tested here is the category of **DNA Repair Deficiency Syndromes** (Genodermatoses). These are conditions where mutations in genes responsible for repairing DNA damage lead to genomic instability and a high predisposition to cancer. **Why Friedreich’s Ataxia is the Correct Answer:** Friedreich’s ataxia is **not** a DNA repair defect. It is an **autosomal recessive trinucleotide repeat disorder** (GAA repeat) in the *FXN* gene on chromosome 9 [3]. This mutation leads to a deficiency in **frataxin**, a mitochondrial protein involved in iron metabolism. The pathology involves neurodegeneration and cardiomyopathy due to mitochondrial dysfunction and oxidative stress, rather than a failure to repair DNA strands [2]. **Analysis of Incorrect Options (DNA Repair Defects):** * **Xeroderma Pigmentosum:** A classic defect in **Nucleotide Excision Repair (NER)** [1]. Patients cannot repair pyrimidine dimers caused by UV radiation, leading to early-onset skin cancers [1]. * **Werner Syndrome:** Known as "Adult Progeria," it is caused by a mutation in the *WRN* gene, which encodes a **DNA helicase** involved in homologous recombination and DNA repair. * **Bloom Syndrome:** Caused by a mutation in the *BLM* gene (RecQ helicase family). It results in a defect in DNA helicase, leading to high rates of **sister chromatid exchange** and chromosomal instability [1]. **High-Yield Clinical Pearls for NEET-PG:** * **Ataxia-Telangiectasia:** Another high-yield DNA repair defect (ATM gene) involving double-strand break repair [1]. * **HNPCC (Lynch Syndrome):** Defect in **Mismatch Repair (MMR)** genes (*MSH2, MLH1*). * **BRCA1/BRCA2:** Defects in **Homologous Recombination** repair. * **Fanconi Anemia:** Defect in the repair of DNA interstrand cross-links [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 322-323. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1300-1301. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Genetic Disorders, p. 177.

Question 348: Post-transplant lymphoma occurs due to proliferation of which of the following cells?

A. T cell
B. B cell (Correct Answer)
C. NK cell
D. Monocyte

Explanation: **Explanation:** Post-Transplant Lymphoproliferative Disorder (PTLD) refers to a spectrum of conditions ranging from benign lymphoid hyperplasia to malignant lymphoma that occurs following solid organ or hematopoietic stem cell transplantation. **Why B cell is correct:** The vast majority (approx. 85-90%) of PTLD cases are of **B-cell origin** [1]. The primary driver is the **Epstein-Barr Virus (EBV)**. In a healthy individual, EBV-infected B cells are kept in check by cytotoxic T-cells [1]. However, in transplant recipients, the use of **iatrogenic immunosuppression** (to prevent graft rejection) impairs T-cell surveillance [2]. This allows EBV to drive the uncontrolled proliferation of B-lymphocytes, leading to immortalization and eventual neoplastic transformation [1]. **Why other options are incorrect:** * **T cell:** While T-cell PTLDs do exist, they are rare and usually occur much later after transplantation. They are often not associated with EBV. * **NK cell:** These are extremely rare forms of PTLD and do not represent the standard pathology tested in exams. * **Monocyte:** PTLD is specifically a "lymphoproliferative" disorder; monocytes belong to the myeloid lineage and are not the cells involved in this pathology. **High-Yield Clinical Pearls for NEET-PG:** * **Most common virus implicated:** EBV (Epstein-Barr Virus) [1]. * **Risk factor:** The intensity of immunosuppression (especially T-cell depleting agents like OKT3 or Anti-thymocyte globulin) [2]. * **Management:** The first line of management is often the **reduction of immunosuppressive therapy**, which allows the host's immune system to recover and attack the proliferating B cells. * **Morphology:** Can range from polymorphic (mixed cells) to monomorphic (resembling Diffuse Large B-cell Lymphoma) [3]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Infectious Diseases, pp. 368-369. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 595-596. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 596-598.

Question 349: Apoptosis is inhibited by which of the following?

A. RAS
B. N-myc
C. Bcl-2 (Correct Answer)
D. All of the above

Explanation: **Explanation:** The correct answer is **C. Bcl-2**. **Mechanism of Action:** Apoptosis (programmed cell death) is regulated by the balance between pro-apoptotic and anti-apoptotic proteins [4]. **Bcl-2** is the prototypical **anti-apoptotic** protein located on the outer mitochondrial membrane [2]. It acts by preventing the leakage of Cytochrome C into the cytosol [1]. It does this by inhibiting the pro-apoptotic proteins **BAX and BAK**, which are responsible for forming pores in the mitochondrial membrane. When Bcl-2 is overexpressed, the cell becomes resistant to apoptosis, a hallmark of many cancers [3]. **Analysis of Incorrect Options:** * **A. RAS:** This is a proto-oncogene involved in **signal transduction**. Mutations in RAS (most commonly point mutations) lead to continuous cell proliferation signals, not direct inhibition of the apoptotic machinery. * **B. N-myc:** This is a **transcription factor** (oncogene). While its amplification (common in Neuroblastoma) drives rapid cell cycle progression and growth, its primary role is not the direct inhibition of apoptosis. * **D. All of the above:** Incorrect because RAS and N-myc primarily drive proliferation, whereas Bcl-2 specifically functions as an apoptosis inhibitor. **High-Yield Clinical Pearls for NEET-PG:** * **Follicular Lymphoma:** Characterized by the **t(14;18)** translocation, which moves the *BCL2* gene to the IgH locus, leading to overexpression of Bcl-2 and subsequent inhibition of apoptosis in B-cells [3]. * **Pro-apoptotic proteins:** BAX, BAK, Bim, Bid, Bad (Mnemonic: "Death" proteins). * **Anti-apoptotic proteins:** Bcl-2, Bcl-xL, MCL-1. * **Guardian of the Genome:** p53 induces apoptosis by upregulating BAX if DNA repair fails [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, p. 310. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Cellular Responses to Stress and Toxic Insults: Adaptation, Injury, and Death, pp. 65-67. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 310-311. [4] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Cellular Responses to Stress and Toxic Insults: Adaptation, Injury, and Death, pp. 64-65.

Question 350: Gleason's score is used for?

A. Prostate carcinoma (Correct Answer)
B. Testicular carcinoma
C. Renal cell carcinoma
D. Malignant melanoma

Explanation: **Explanation:** **Gleason’s Scoring System** is the gold standard for grading **Prostate Carcinoma** [1]. Unlike many other cancers that use cellular atypia, the Gleason system is based solely on the **architectural patterns** of the tumor cells. It assesses how well the neoplastic cells form glands [2]. * **Why it is correct:** The score is calculated by adding the primary (most dominant) pattern and the secondary (second most dominant) pattern. Each is graded from 1 (well-differentiated) to 5 (no glandular differentiation). The total score ranges from 2 to 10. A higher score indicates a more aggressive tumor and a poorer prognosis [1], [2]. **Analysis of Incorrect Options:** * **Testicular Carcinoma:** These are primarily staged using the TNM system and serum tumor markers (AFP, hCG, LDH). Grading systems like Gleason are not applied here. * **Renal Cell Carcinoma (RCC):** The standard grading system for RCC is the **Fuhrman Nuclear Grade** (or the updated ISUP/WHO system), which focuses on nuclear size, contour, and nucleolar prominence. * **Malignant Melanoma:** Prognosis is determined by the **Breslow Depth** (thickness in mm) and **Clark Level** (anatomical layer of invasion), not a Gleason-like architectural score. **High-Yield Clinical Pearls for NEET-PG:** * **Gleason Grade Groups:** Modern pathology now groups scores into five categories (Grade Group 1 to 5) to better reflect clinical outcomes (e.g., Score ≤6 is Grade Group 1). * **Prostate Biopsy:** In a biopsy, if only one pattern is seen, it is doubled (e.g., 3+3=6). If three patterns are present, the most common and the *highest* grade are added. * **Site:** Prostate cancer most commonly arises in the **peripheral zone**, making it detectable via Digital Rectal Examination (DRE) [1], [3]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lower Urinary Tract and Male Genital System, pp. 993-994. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lower Urinary Tract and Male Genital System, pp. 990-992. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lower Urinary Tract and Male Genital System, pp. 989-990.

Practice by Chapter

Nomenclature and Classification of Tumors

Practice Questions

Characteristics of Benign and Malignant Neoplasms

Practice Questions

Molecular Basis of Cancer

Practice Questions

Carcinogenesis and Carcinogens

Practice Questions

Tumor Progression and Metastasis

Practice Questions

Tumor Markers

Practice Questions

Paraneoplastic Syndromes

Practice Questions

Genetic Basis of Cancer

Practice Questions

Tumor Immunity

Practice Questions

Cancer Epidemiology and Prevention

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free

Neoplasia — MCQs

Neoplasia — MCQs

On this page

Practice by Chapter

Want unlimited practice?