Biopsy Principles — MCQs
Which of the following is a differential of giant cell tumor?
Most sensitive modality for detecting bone metastases
Which one of the following is not a principle followed in the management of missile injuries?
Identify the given bone marrow biopsy instrument
A 28-year-old lady presented with wrist pain. X-ray of the wrist shows a lytic eccentric lesion in the lower end of the radius with a soap bubble appearance. What is the next plan of management?
Biopsy of a clinically suspicious lesion is negative. The most appropriate treatment is
Distant bone metastases can be best detected by which of the following imaging techniques?
An elderly patient presents with a non-healing ulcerative lesion on the lower lip, as shown in the image. The lesion has been gradually enlarging over the past few months. Suspecting squamous cell carcinoma (SCC), what is the most appropriate method to obtain a biopsy for definitive diagnosis?
A 10 cm tumor is found on the anterior surface of the thigh. What is the most appropriate procedure to obtain a diagnosis?
A 45 yrs male presented with an expansile lesion in the centre of femoral metaphysis. The lesion shows Endosteal scalloping and punctuate calcifications. Most likely diagnosis is:
Biopsy Principles Indian Medical PG Practice Questions and MCQs
Question 1: Which of the following is a differential of giant cell tumor?
- A. Chondroblastoma (Correct Answer)
- B. Osteogenic sarcoma
- C. Ossifying fibroma
- D. Non-ossifying fibroma
Explanation: **Chondroblastoma** - Both **Chondroblastoma** and **giant cell tumor (GCT)** are epiphyseal lesions that can occur in a similar age group and have some overlapping radiographic features, making them a differential. - Histologically, chondroblastoma can contain **multinucleated giant cells**, which may be confused with those found in GCT. *Osteogenic sarcoma* - **Osteogenic sarcoma (osteosarcoma)** is a malignant bone tumor primarily affecting the metaphysis of long bones, in contrast to GCT's epiphyseal location [1]. - Radiographically, osteosarcoma often presents with an aggressive, destructive pattern including **periosteal reaction** (e.g., sunburst, Codman's triangle), which is less typical for GCT [1]. *Ossifying fibroma* - **Ossifying fibroma** is a benign fibro-osseous lesion most commonly found in the jaws, distinctly different from GCT's predilection for epiphyses of long bones. - Histologically, it's characterized by the presence of **mineralized material** resembling bone or cementum within a fibrous stroma, unlike the abundant multinucleated giant cells of GCT [1]. *Non-ossifying fibroma* - A **non-ossifying fibroma (NOF)**, also known as a fibrous cortical defect, is typically a benign, asymptomatic, and self-limiting lesion found in the metaphysis of long bones, usually in children and adolescents. - It is characterized by **fibrous tissue** and foam cells but lacks the prominent multinucleated giant cells and epiphyseal location characteristic of GCT [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, pp. 1205-1206. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, p. 1208.
Question 2: Most sensitive modality for detecting bone metastases
- A. Bone scan
- B. PET-CT
- C. Plain radiograph
- D. MRI (Correct Answer)
Explanation: ***MRI*** - **MRI**, especially **whole-body MRI (WB-MRI)**, has the **highest sensitivity (90-100%)** for detecting bone metastases among all imaging modalities. - It directly visualizes **bone marrow changes** before cortical bone destruction occurs, allowing for earlier detection than other modalities. - Excellent for detecting both **lytic and sclerotic lesions** and provides superior soft tissue contrast for assessing marrow involvement. - Particularly sensitive for **spine and pelvic metastases**, and whole-body protocols enable comprehensive skeletal assessment. *PET-CT* - **PET-CT with 18F-FDG** is highly sensitive for detecting metabolically active lesions and provides whole-body assessment with both metabolic and anatomical information. - However, its sensitivity varies by primary tumor type and is **limited for sclerotic/osteoblastic metastases** which may not be FDG-avid. - While excellent for many malignancies, it has **lower sensitivity than MRI** for pure bone metastases detection, particularly in low-metabolism lesions. *Bone scan* - **Bone scan (Tc-99m MDP)** detects increased osteoblastic activity and has been the traditional screening tool with good sensitivity (62-89%). - Effective for detecting osteoblastic lesions and provides whole-body skeletal survey at relatively low cost. - However, it is **less sensitive than MRI** and can miss purely lytic metastases or early marrow involvement before osteoblastic response occurs. *Plain radiograph* - **Plain radiographs** require significant bone mineral loss (30-50%) to visualize lesions, making them the **least sensitive modality** for bone metastases. - Useful for assessing established lesions and complications like pathological fractures, but inadequate for screening or early detection.
Question 3: Which one of the following is not a principle followed in the management of missile injuries?
- A. Excision of all dead muscles
- B. Removal of foreign bodies
- C. Leaving the wound open
- D. Removal of fragments of bone (Correct Answer)
Explanation: ***Removal of fragments of bone*** - While large, easily accessible bone fragments that are likely to cause future complications (e.g., nerve compression) might be removed, the general principle in missile injuries is **not to routinely remove all bone fragments**. - Small, embedded bone fragments often act as a scaffold for healing and may not pose a significant threat if sterile, and aggressive removal can cause further trauma. *Excision of all dead muscles* - This is a fundamental principle in the management of missile injuries to prevent **infection** and promote healing. - **Debridement** of all non-viable tissue, including dead muscle, is crucial to remove potential sources of bacterial growth and toxins. *Removal of foreign bodies* - This is also a crucial principle to prevent **infection**, **inflammation**, and potential long-term complications. - Foreign bodies like bullet fragments, clothing, or dirt can introduce bacteria and hinder wound healing. *Leaving the wound open* - This is a standard practice for most missile wounds, especially those with significant tissue damage or contamination, to allow for **drainage** and prevent **compartment syndrome**. - **Delayed primary closure** may be performed after a few days if the wound is clean and free of infection, but initial closure is generally avoided.
Question 4: Identify the given bone marrow biopsy instrument
- A. Jamshidi needle (Correct Answer)
- B. Salah needle
- C. Tru-cut needle
- D. Vim Silverman needle
Explanation: ***Jamshidi needle*** - The image displays a **Jamshidi needle**, characterized by its **tapered, beveled tip** designed to facilitate entry into the bone and procure an intact core of bone marrow. - This needle is widely considered the **gold standard** for bone marrow biopsy due to its effectiveness in obtaining high-quality trephine samples. *Salah needle* - A Salah needle is primarily used for **bone marrow aspiration**, not typically for a trephine biopsy, and it has a different design meant for aspirating liquid marrow. - It features a **shorter, sturdier design** with a sharp bevel, optimized for safely extracting marrow fluid. *Tru-cut needle* - The Tru-cut needle is primarily designed for obtaining **soft tissue biopsies** (e.g., liver, kidney, prostate) and is not typically used for bone marrow biopsies. - Its mechanism involves an inner cutting stylet and an outer cutting cannula, which is unsuitable for penetrating dense bone and retrieving a bone core. *Vim Silverman needle* - The Vim Silverman needle is also designed for **soft tissue biopsies**, similar to the Tru-cut, and not specifically for bone marrow. - It utilizes a split needle design to capture tissue, which is not appropriate for obtaining a solid bone marrow core.
Question 5: A 28-year-old lady presented with wrist pain. X-ray of the wrist shows a lytic eccentric lesion in the lower end of the radius with a soap bubble appearance. What is the next plan of management?
- A. Extended curettage with phenol
- B. Biopsy of the lesion (Correct Answer)
- C. Bone curettage and bone grafting
- D. Extended curettage with phenol and bone grafting
Explanation: ***Biopsy of the lesion*** - A definitive **diagnosis is crucial** before any surgical intervention for a bone lesion, especially one with a characteristic appearance like "soap bubble." Biopsy will confirm the nature of the lesion, ruling out malignancy and guiding treatment. - The presented lesion, with its **lytic, eccentric, soap-bubble appearance** in the lower radius of a young adult, is highly suggestive of a **giant cell tumor (GCT)**. However, other diagnoses like chondroblastoma or aneurysmal bone cyst (ABC) can also mimic this appearance. *Extended curettage with phenol* - This is a treatment option for certain benign aggressive bone tumors like **giant cell tumors** after diagnosis, not the initial diagnostic step. - Performing this procedure without a **histological diagnosis** could lead to inappropriate treatment for other possible lesions. *Bone curettage and bone grafting* - This is a surgical treatment method typically used for **benign bone tumors** to remove the lesion and fill the defect, but it is performed after a definitive diagnosis. - **Performing it blindly** without knowing the exact pathology carries the risk of inadequate treatment or unnecessary surgery for a lesion that might require different management. *Extended curettage with phenol and bone grafting* - This comprehensive treatment often follows a **confirmed diagnosis** of an aggressive but benign bone tumor like GCT to minimize recurrence. - It is not the **initial diagnostic step** and carries risks if the underlying pathology is not accurately identified.
Question 6: Biopsy of a clinically suspicious lesion is negative. The most appropriate treatment is
- A. Repeat the biopsy for further evaluation. (Correct Answer)
- B. Monitor the patient closely for twelve months.
- C. Monitor the patient closely for three months.
- D. Reassure the patient that the lesion is benign.
Explanation: ***Repeat the biopsy for further evaluation.*** - A **clinically suspicious lesion** with a negative biopsy result warrants a repeat biopsy because a **false negative** is possible, especially if the initial sample was inadequate or not representative. - The principle "**never let the sun set on a clinically suspicious lesion**" applies here - clinical suspicion should override a negative biopsy result. - Repeating the procedure ensures accurate diagnosis, which is crucial for lesions with **malignant potential**. *Monitor the patient closely for twelve months.* - This approach is too **conservative** for a clinically suspicious lesion with a negative biopsy, as a malignancy could progress significantly within a year. - Waiting this long without a definitive diagnosis carries an **unacceptable risk** of delayed treatment for a potential cancer. *Monitor the patient closely for three months.* - While more proactive than waiting a year, **three months** is still too long for a clinically suspicious lesion if the biopsy result is unreliable. - Early detection and diagnosis are paramount for better outcomes in potentially **malignant lesions**. *Reassure the patient that the lesion is benign.* - This is **inappropriate** as it accepts the false negative biopsy result at face value and dismisses the clinical suspicion. - **Clinical judgment** should take precedence over a negative biopsy when a lesion remains suspicious. - This approach could lead to **catastrophic delays** in diagnosing malignancy.
Question 7: Distant bone metastases can be best detected by which of the following imaging techniques?
- A. Bone scan (Correct Answer)
- B. CT
- C. Intravenous venogram
- D. PET scan
Explanation: ***Bone scan*** - A **bone scan** is highly sensitive for detecting **osteoblastic activity**, which is characteristic of most bone metastases. - It involves injecting a **radioactive tracer** (usually technetium-99m methylene diphosphonate) that accumulates in areas of increased bone turnover, making it excellent for surveying the entire skeletal system. *PET scan* - While a **PET scan** (Positron Emission Tomography) can detect bone metastases, especially with **FDG-PET**, it is generally more expensive and may not be as sensitive for purely **osteoblastic lesions** as a bone scan. - Its primary role is often in assessing metabolic activity of the primary tumor and other distant soft tissue metastases. *CT* - **CT scans** (Computed Tomography) are excellent for assessing bone anatomy, cortical destruction, and soft tissue involvement, but they are generally less sensitive for detecting early or widespread **osseous metastatic disease** compared to a bone scan. - CT provides detailed anatomical information but may miss early **marrow involvement** that alters bone metabolism. *Intravenous venogram* - An **intravenous venogram** is an imaging technique used to visualize veins, primarily for detecting **thrombosis** or venous insufficiency. - It has no role in the detection of **bone metastases**, as it provides no information about bone structure or metabolic activity.
Question 8: An elderly patient presents with a non-healing ulcerative lesion on the lower lip, as shown in the image. The lesion has been gradually enlarging over the past few months. Suspecting squamous cell carcinoma (SCC), what is the most appropriate method to obtain a biopsy for definitive diagnosis?
- A. Incisional (Correct Answer)
- B. Excisional
- C. Deep tissue biopsy
- D. Superficial biopsy from the border with normal tissue
Explanation: ***Incisional*** - An **incisional biopsy** is the most appropriate method for obtaining a definitive diagnosis of suspected squamous cell carcinoma (SCC) of the lip. - This technique involves removing a **wedge-shaped portion of the lesion** that includes both the tumor tissue and a margin extending into normal tissue, with adequate depth to assess invasion. - Incisional biopsy provides sufficient tissue for **histopathological examination**, including assessment of tumor grade, depth of invasion, and other prognostic factors critical for staging and treatment planning. - For larger or suspicious lesions where complete excision might cause significant cosmetic deformity, incisional biopsy allows for **diagnosis confirmation before definitive surgical management**. *Superficial biopsy from the border with normal tissue* - A superficial or shave biopsy is **inadequate for SCC diagnosis** as it does not provide information about the depth of invasion, which is crucial for staging and prognosis. - Squamous cell carcinoma requires assessment of invasion into underlying dermis and deeper structures, which cannot be evaluated with superficial sampling. - Superficial biopsies may lead to **underdiagnosis** or incomplete staging, potentially compromising treatment planning. *Excisional* - While excisional biopsy (complete removal with margins) can be appropriate for **small, well-defined lesions** (<1 cm), it may not be the first choice for larger or gradually enlarging lesions. - Complete excision without prior histological confirmation might result in **inadequate margins** if malignancy is confirmed, requiring re-excision. - For lip lesions, unnecessary wide excision can cause **significant cosmetic and functional defects** if the lesion proves benign or requires specialized reconstruction. *Deep tissue biopsy* - This is not standard terminology in the context of lip lesions and lacks specificity regarding the sampling technique. - The term "deep tissue biopsy" is more commonly used for suspected soft tissue tumors or deep-seated lesions, not for mucocutaneous SCC.
Question 9: A 10 cm tumor is found on the anterior surface of the thigh. What is the most appropriate procedure to obtain a diagnosis?
- A. Incision biopsy (Correct Answer)
- B. Excision biopsy
- C. FNAC
- D. USG
Explanation: ***Incision biopsy*** - An **incision biopsy** is most appropriate for a large tumor (10 cm) to obtain a tissue diagnosis without performing a potentially morbid or disfiguring complete excision upfront. - It involves removing a representative section of the tumor for histopathological analysis, providing adequate tissue for diagnosis, grading, and subtyping. - This allows definitive treatment planning based on confirmed histopathology. *Excision biopsy* - **Excision biopsy** is generally reserved for smaller tumors (typically <3-5 cm) that can be completely resected with acceptable cosmetic and functional outcomes. - Excision of a 10 cm tumor on the thigh would be a significant surgical procedure, potentially causing substantial morbidity, without a prior definitive diagnosis. - Could compromise subsequent definitive surgery if margins are inadequate. *FNAC* - **FNAC (Fine Needle Aspiration Cytology)** provides only cytological diagnosis, which is insufficient for definitive diagnosis, grading, and subtyping of soft tissue tumors, especially sarcomas. - It misses crucial architectural features and tissue patterns needed for accurate classification. - May yield inadequate or non-diagnostic samples from large heterogeneous tumors. *USG* - **USG (Ultrasound)** is an imaging modality, not a tissue diagnosis procedure. - While useful for characterizing mass features (size, location, vascularity, solid vs cystic), it cannot provide histopathological diagnosis. - The question specifically asks for a procedure to "obtain a diagnosis," which requires tissue sampling for microscopic examination.
Question 10: A 45 yrs male presented with an expansile lesion in the centre of femoral metaphysis. The lesion shows Endosteal scalloping and punctuate calcifications. Most likely diagnosis is:
- A. Fibrous Dysplasia
- B. Chondrosarcoma (Correct Answer)
- C. Simple bone cyst
- D. Osteosarcoma
Explanation: ***Chondrosarcoma*** - An **expansile lesion** within the **femoral metaphysis** with **endosteal scalloping** and **punctate calcifications** is highly characteristic of a chondrosarcoma. - The punctate/arc-and-ring calcifications are typical for cartilage matrix, which is the hallmark of chondrosarcoma, and the patient's age (45 years) fits the typical demographic. *Fibrous Dysplasia* - This condition presents as a **ground-glass matrix** on imaging, not punctate calcifications. - While it can be expansile, it typically does not show prominent endosteal scalloping with cartilage calcifications. *Simple bone cyst* - Simple bone cysts are typically **lytic lesions** that do not show punctate calcifications or aggressive endosteal scalloping. - They are often **fluid-filled** and common in children/adolescents, whereas this patient is 45 years old. *Osteosarcoma* - Osteosarcomas are characterized by **osteoid matrix formation** and often have a more aggressive appearance with a **sunburst or spiculated periosteal reaction** and bone formation, not punctate cartilage calcifications. - While it can be expansile, the calcification pattern described points away from osteosarcoma.
Want unlimited practice?
Get full access to all questions, explanations, and performance tracking.
Start For Free