Neoplasia US Medical PG Practice Questions and MCQs
Practice US Medical PG questions for Neoplasia. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Neoplasia US Medical PG Question 1: A 33-year-old woman comes to the physician 1 week after noticing a lump in her right breast. Fifteen years ago, she was diagnosed with osteosarcoma of her left distal femur. Her father died of an adrenocortical carcinoma at the age of 41 years. Examination shows a 2-cm, firm, immobile mass in the lower outer quadrant of the right breast. A core needle biopsy of the mass shows adenocarcinoma. Genetic analysis in this patient is most likely to show a defect in which of the following genes?
- A. BRCA1
- B. KRAS
- C. TP53 (Correct Answer)
- D. Rb
- E. PTEN
Neoplasia Explanation: ***TP53***
- This patient's presentation with **early-onset breast cancer**, a history of **osteosarcoma** at a young age, and a father's death from **adrenocortical carcinoma** at 41 years strongly suggests **Li-Fraumeni syndrome**.
- Li-Fraumeni syndrome is an autosomal dominant disorder caused by a germline mutation in the **tumor suppressor gene TP53**, increasing the risk for multiple primary cancers at a young age.
*BRCA1*
- While **BRCA1 mutations** are associated with an increased risk of breast and ovarian cancer, they are not typically linked to osteosarcoma or adrenocortical carcinoma.
- The constellation of cancers in this patient is more indicative of Li-Fraumeni syndrome than solely a BRCA1-related cancer syndrome.
*KRAS*
- **KRAS** is an oncogene commonly mutated in several cancers, including pancreatic, colorectal, and lung cancer, but is not primarily associated with either Li-Fraumeni syndrome or the specific tumors seen in this family history.
- Mutations in KRAS are typically somatic mutations acquired during a person's lifetime, not germline mutations causing inherited cancer syndromes like the one suggested here.
*Rb*
- Mutations in the **retinoblastoma (Rb) gene** are associated with retinoblastoma and an increased risk of osteosarcoma, but not typically with adrenocortical carcinoma or breast cancer as part of a classic inherited syndrome.
- The combination of breast cancer, osteosarcoma, and adrenocortical carcinoma points more specifically to TP53.
*PTEN*
- **PTEN mutations** are associated with Cowden syndrome, which increases the risk for breast cancer, thyroid cancer, and endometrial cancer, along with benign growths.
- However, Cowden syndrome does not typically include osteosarcoma or adrenocortical carcinoma as prominent features, making PTEN less likely than TP53 for this specific family history.
Neoplasia US Medical PG Question 2: A 62-year-old woman presents to her physician with a painless breast mass on her left breast for the past 4 months. She mentions that she noticed the swelling suddenly one day and thought it would resolve by itself. Instead, it has been slowly increasing in size. On physical examination of the breasts, the physician notes a single non-tender, hard, and fixed nodule over left breast. An ultrasonogram of the breast shows a solid mass, and a fine-needle aspiration biopsy confirms the mass to be lobular carcinoma of the breast. When the patient asks about her prognosis, the physician says that the prognosis can be best determined after both grading and staging of the tumor. Based on the current diagnostic information, the physician says that they can only grade, but no stage, the neoplasm. Which of the following facts about the neoplasm is currently available to the physician?
- A. The tumor invades the pectoralis major.
- B. The tumor has spread via blood-borne metastasis.
- C. The tumor has not metastasized to the contralateral superior mediastinal lymph nodes.
- D. The tumor has metastasized to the axillary lymph nodes.
- E. The tumor cells exhibit marked nuclear atypia. (Correct Answer)
Neoplasia Explanation: ***The tumor cells exhibit marked nuclear atypia.***
- **Grading** assesses the **histological appearance** of cancer cells and tissues, including features like nuclear atypia, mitotic rate, and architectural features, which are directly observable from the **fine-needle aspiration biopsy**.
- **Nuclear atypia** refers to abnormal changes in the size, shape, and chromatin pattern of cell nuclei, indicating a higher degree of anaplasia and aggressiveness.
*The tumor invades the pectoralis major.*
- **Invasion into surrounding tissues**, especially muscle, is a feature determined during **surgical staging** or comprehensive imaging, which is not described as being performed yet.
- This information relates to the **"T" (tumor size/extension)** component of TNM staging, which cannot be fully assessed with only a biopsy.
*The tumor has spread via blood-borne metastasis.*
- **Distant metastasis** is part of the **"M" (metastasis)** component of TNM staging, requiring imaging studies (e.g., PET scan, CT scan) or biopsies of suspected metastatic sites.
- The current diagnostic information (biopsy of the primary tumor) does not provide details about **blood-borne spread**.
*The tumor has not metastasized to the contralateral superior mediastinal lymph nodes.*
- Information about **lymph node involvement**, even in distant locations like the mediastinum, falls under the **"N" (nodes)** component of TNM staging, which requires thorough imaging or surgical dissection.
- The current biopsy focuses on the primary breast mass and cannot rule out distant lymph node metastasis.
*The tumor has metastasized to the axillary lymph nodes.*
- **Axillary lymph node metastasis** is also part of the **"N" component** of staging and is typically determined by sentinel lymph node biopsy or axillary dissection performed during surgery, or through imaging.
- A fine-needle aspiration of the primary breast mass does not provide information about regional lymph node involvement.
Neoplasia US Medical PG Question 3: Patient 1 – A 26-year-old woman presents to her primary care physician for an annual exam. She currently does not have any acute concerns and says her health has been generally well. Medical history is significant for asthma, which is managed with an albuterol inhaler. Her last pap smear was unremarkable. She is currently sexually active with one male and consistently uses condoms. She occasionally smokes marijuana and drinks wine once per week. Her mother recently passed away from advanced ovarian cancer. Her sister is 37-years-old and was recently diagnosed with breast cancer and ovarian cancer. Physical examination is remarkable for a mildly anxious woman.
Patient 2 – A 27-year-old woman presents to her primary care physician for an annual exam. She says that she would like to be screened for breast cancer since two of her close friends were recently diagnosed. She noticed she has a small and mobile mass on her left breast, which increases in size and becomes tender around her time of menses. Family history is remarkable for hypertension in the father. The physical exam is significant for a small, well-defined, and mobile mass on her left breast that is not tender to palpation.
Which of the following is the best next step in management for patient 1 and 2?
- A. Patient 1 – Breast ultrasound. Patient 2 – Return in 3 months for a clinical breast exam
- B. Patient 1 – Reassurance. Patient 2 – Breast ultrasound
- C. Patient 1 – CA-125 testing. Patient 2 – BRCA testing
- D. Patient 1 – BRCA testing. Patient 2 – Breast ultrasound (Correct Answer)
- E. Patient 1 – Breast and ovarian ultrasound. Patient 2 – Mammography
Neoplasia Explanation: ***Patient 1 – BRCA testing. Patient 2 – Breast ultrasound***
- Patient 1 has a strong family history of early-onset **breast and ovarian cancer** (**mother and sister**), suggesting a high probability of an inherited genetic mutation, such as **BRCA1/2**, which warrants genetic testing.
- Patient 2 presents with a **small, mobile, well-defined breast mass** that is likely benign, and a **breast ultrasound** is the appropriate initial imaging for further characterization in a young woman.
*Patient 1 – Breast ultrasound. Patient 2 – Return in 3 months for a clinical breast exam*
- Patient 1's primary concern is genetic predisposition due to family history, an **ultrasound** is not the initial or primary screening method for future cancer risk.
- Patient 2 has a palpable mass; waiting 3 months for a **clinical breast exam** without initial imaging (ultrasound) is not appropriate for evaluating a new breast lump.
*Patient 1 – Reassurance. Patient 2 – Breast ultrasound*
- Patient 1's family history of **early-onset breast and ovarian cancer** is a significant risk factor; therefore, simple **reassurance** without further investigation is inappropriate.
- While a **breast ultrasound** is appropriate for Patient 2, the recommendation for Patient 1 is incorrect.
*Patient 1 – CA-125 testing. Patient 2 – BRCA testing*
- **CA-125** is a tumor marker primarily used for monitoring ovarian cancer treatment or recurrence, not for initial screening in asymptomatic individuals, especially in a young woman with no active symptoms.
- **BRCA testing** is indicated for Patient 1 due to family history, but not for Patient 2 who has a likely benign breast mass and no significant family history.
*Patient 1 – Breast and ovarian ultrasound. Patient 2 – Mammography*
- Regular **breast and ovarian ultrasounds** are not recommended as primary screening tools for genetic risk in asymptomatic high-risk individuals like Patient 1.
- **Mammography** is less sensitive in young women (under 30) due to higher breast tissue density, making **ultrasound** the preferred initial imaging for Patient 2.
Neoplasia US Medical PG Question 4: An epidemiologist is evaluating the efficacy of Noxbinle in preventing HCC deaths at the population level. A clinical trial shows that over 5 years, the mortality rate from HCC was 25% in the control group and 15% in patients treated with Noxbinle 100 mg daily. Based on this data, how many patients need to be treated with Noxbinle 100 mg to prevent, on average, one death from HCC?
- A. 20
- B. 73
- C. 10 (Correct Answer)
- D. 50
- E. 100
Neoplasia Explanation: ***10***
- The **number needed to treat (NNT)** is calculated by first finding the **absolute risk reduction (ARR)**.
- **ARR** = Risk in control group - Risk in treatment group = 25% - 15% = **10%** (or 0.10).
- **NNT = 1 / ARR** = 1 / 0.10 = **10 patients**.
- This means that **10 patients must be treated with Noxbinle to prevent one death from HCC** over 5 years.
*20*
- This would result from an ARR of 5% (1/0.05 = 20), which is not supported by the data.
- May arise from miscalculating the risk difference or incorrectly halving the actual ARR.
*73*
- This value does not correspond to any standard calculation of NNT from the given mortality rates.
- May result from confusion with other epidemiological measures or calculation error.
*50*
- This would correspond to an ARR of 2% (1/0.02 = 50), which significantly underestimates the actual risk reduction.
- Could result from incorrectly calculating the difference as a proportion rather than absolute percentage points.
*100*
- This would correspond to an ARR of 1% (1/0.01 = 100), grossly underestimating the treatment benefit.
- May result from confusing ARR with relative risk reduction or other calculation errors.
Neoplasia US Medical PG Question 5: A 39-year-old African American woman is admitted to the hospital following a seizure with a severe post-ictal headache. She was diagnosed with breast cancer 1 year ago when she presented with a hard, rock-like, immobile mass with irregular borders accompanied by changes in the breast skin, including erythema and dimpling. She had ipsilateral mobile axillary lymphadenopathy at that time. A biopsy confirmed the diagnosis of stage 2B invasive breast cancer. Her mother died at 42 years of age due to the same type of breast cancer. A CT scan done during this admission reveals multiple metastatic lesions in the brain and liver, along with the involvement of supra- and infra-clavicular lymph nodes. Which of the following molecular profile most likely characterizes this patient?
- A. PR, ER, HER2 positive
- B. HER2 positive
- C. Progesterone receptor (PR) positive
- D. ER, PR, HER2 negative (Correct Answer)
- E. Estrogen receptor (ER) positive
Neoplasia Explanation: ***ER, PR, HER2 negative***
- This patient's presentation with aggressive breast cancer at a relatively young age (39 years old), family history of early-onset breast cancer, rapid progression to metastatic disease in the brain and liver, and involvement of multiple lymph nodes (axillary, supra- and infra-clavicular) are all highly suggestive of a **triple-negative breast cancer (TNBC)**.
- TNBC is characterized by the absence of **estrogen receptors (ER)**, **progesterone receptors (PR)**, and **human epidermal growth factor receptor 2 (HER2)** overexpression, making it an aggressive subtype with limited targeted treatment options and a poor prognosis, consistent with the patient's rapidly worsening condition.
*PR, ER, HER2 positive*
- This molecular profile (also known as triple-positive breast cancer) generally indicates a more favorable prognosis due to the availability of **hormonal therapy** (for ER/PR positivity) and **anti-HER2 targeted therapy**.
- The aggressive course and rapid metastatic spread described in the patient are less typical for triple-positive disease, which often responds well to various targeted treatments.
*HER2 positive*
- HER2-positive breast cancer can be aggressive, but the presence of HER2 positivity allows for **HER2-targeted therapies** (e.g., trastuzumab, pertuzumab), which significantly improve outcomes.
- While HER2-positive cancers can metastasize to the brain, the overall clinical picture, especially the aggressive growth and lack of other receptor expression, aligns more with triple-negative disease.
*Progesterone receptor (PR) positive*
- PR positivity, often alongside ER positivity, indicates a **hormone-sensitive breast cancer**, which typically has a better prognosis and is amenable to **endocrine therapy**.
- The aggressive and rapid metastatic progression to multiple sites, including brain and liver, is not characteristic of a purely PR-positive tumor without other aggressive features.
*Estrogen receptor (ER) positive*
- ER-positive breast cancer is the most common subtype and is generally associated with a **better prognosis** and responsiveness to **endocrine therapy**.
- The patient's aggressive disease course, including early metastasis and family history of early-onset, aggressive breast cancer, does not align with the typical presentation of an exclusively ER-positive tumor.
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