Tumor Ablation Techniques — MCQs

10 questions

Which of the following surgical incisions is associated with the highest risk of postoperative pulmonary complications ?

Radiofrequency ablation is commonly performed for which of the following conditions?

Stereotactic Radiosurgery is a form of –

A 60-year-old male with a history of cirrhosis presents with a 4 cm hepatocellular carcinoma (HCC) located in segment VII of the liver. Considering the patient has Child-Pugh A liver function, which clinical factors are most critical in deciding between liver resection and radiofrequency ablation (RFA)?

Which of the following is the platinum-based chemotherapeutic agent used as first-line treatment for ovarian carcinoma?

A lady presented with a 4 cm tumor in the left parietal lobe for which she underwent surgery and radiotherapy. After 3 months she presented with headache and vomiting. Which of the following would characterize the lesion in the patient?

Gold standard investigation for breast carcinoma screening in a patient with silicone breast implants

What is the treatment of choice for a post-operative abscess?

Heat-labile instruments for use in surgical procedures can be best sterilized by what method?

Q10

Best treatment for stage III frostbite is:

Tumor Ablation Techniques Indian Medical PG Practice Questions and MCQs

Question 1: Which of the following surgical incisions is associated with the highest risk of postoperative pulmonary complications ?

A. Median sternotomy
B. Horizontal laparotomy
C. Vertical laparotomy
D. Lateral thoracotomy (Correct Answer)

Explanation: ***Lateral thoracotomy*** - **Lateral thoracotomy** is associated with the **highest risk of postoperative pulmonary complications** among common surgical incisions, with complication rates ranging from **15-70%** depending on the procedure. - This incision **directly violates the chest wall** with rib resection or spreading, causing severe postoperative pain that significantly impairs respiratory mechanics. - The procedure disrupts **intercostal muscles**, damages **intercostal nerves**, and violates the **pleura**, leading to immediate risks like **pneumothorax**, **hemothorax**, and **pleural effusion**. - Severe pain leads to **splinting**, **shallow breathing**, **impaired cough**, and **reduced lung expansion**, markedly increasing the risk of **atelectasis**, **pneumonia**, and **respiratory failure**. - The **ipsilateral lung** is particularly affected with reduced functional residual capacity and impaired secretion clearance. *Vertical laparotomy* - **Upper abdominal vertical incisions** are indeed associated with high pulmonary complication rates (**30-50%**), second only to thoracotomy. - Pain leads to **diaphragmatic splinting** and impaired respiratory mechanics, increasing risk of **atelectasis** and **pneumonia**. - However, the chest wall itself remains intact, making complications generally less severe than with thoracotomy. *Median sternotomy* - While a major thoracic procedure, **median sternotomy** has relatively **lower pulmonary complication rates** compared to lateral thoracotomy. - The sternal split preserves **intercostal muscles** and **nerve integrity**, resulting in less severe pain and better preserved respiratory mechanics. - Postoperative pain management is generally more effective than with lateral thoracotomy. *Horizontal laparotomy* - **Transverse abdominal incisions** (e.g., Pfannenstiel, transverse supraumbilical) cause significantly less pain than vertical incisions. - These incisions follow **natural tissue planes**, cause less muscle disruption, and allow better respiratory mechanics. - Lower pain levels facilitate **effective coughing**, **deep breathing**, and **early mobilization**, reducing pulmonary complication risk.

Question 2: Radiofrequency ablation is commonly performed for which of the following conditions?

A. Paroxysmal supraventricular tachycardia (PSVT) (Correct Answer)
B. Ventricular tachycardia
C. Atrial tachycardia
D. Wolff-Parkinson-White (WPW) syndrome

Explanation: ***Paroxysmal supraventricular tachycardia (PSVT)*** - **Radiofrequency ablation (RFA)** is a common and highly effective treatment for PSVT, targeting the **accessory pathways** or reentrant circuits responsible for the arrhythmia [1]. - It works by using heat to create a small lesion in the abnormal tissue, **blocking the electrical signals** that cause the rapid heart rate [1]. *Ventricular tachycardia* - While RFA can be used for some forms of **ventricular tachycardia (VT)**, it is generally reserved for specific types or when antiarrhythmic medications are ineffective [1]. - VT often arises from structural heart disease, making ablation more complex and sometimes less successful than for PSVT. *Atrial tachycardia* - **Atrial tachycardia** can be treated with RFA, but it is typically a more complex procedure than for PSVT due to the variety of potential reentrant circuits or focal origins within the atria [1]. - Success rates for atrial tachycardia ablation can be lower than for PSVT, depending on the specific mechanism and location of the arrhythmia. *Wolff-Parkinson-White (WPW) syndrome* - **Wolff-Parkinson-White (WPW) syndrome** is characterized by an **accessory pathway** that bypasses the AV node, predisposing individuals to reentrant tachycardias, including PSVT [2]. - RFA is indeed a definitive treatment for WPW, but the condition itself is a syndrome that *causes* arrhythmias like PSVT, rather than being the arrhythmia itself.

Question 3: Stereotactic Radiosurgery is a form of –

A. Radioiodine therapy
B. Cryosurgery
C. Robotic Surgery
D. Radiotherapy (Correct Answer)

Explanation: ***Radiotherapy*** - **Stereotactic radiosurgery** is a highly precise form of **radiotherapy** that delivers a single high dose or multiple fractionated high doses of radiation to a specific target area. - It uses focused **radiation beams** to treat tumors or other lesions, often as an alternative to conventional surgery, by causing damage to the DNA of target cells. *Radioiodine therapy* - **Radioiodine therapy** primarily uses **iodine-131** to treat thyroid conditions like hyperthyroidism or thyroid cancer. - This involves the patient ingesting a radioactive isotope, unlike the external radiation beams used in radiosurgery. *Cryo Surgery* - **Cryosurgery** involves the use of **extreme cold** to destroy abnormal tissues. - It is a physical method of tissue destruction and does not involve radiation. *Robotic Surgery* - **Robotic surgery** utilizes robotic systems to assist in performing surgical procedures, enhancing precision, and control for the surgeon. - This is a mode of performing traditional surgery and does not involve radiation as its primary therapeutic agent.

Question 4: A 60-year-old male with a history of cirrhosis presents with a 4 cm hepatocellular carcinoma (HCC) located in segment VII of the liver. Considering the patient has Child-Pugh A liver function, which clinical factors are most critical in deciding between liver resection and radiofrequency ablation (RFA)?

A. Tumor size, location, liver function, and portal hypertension status (Correct Answer)
B. Presence of comorbidities and performance status
C. Tumor vascular invasion and metastasis
D. Patient’s age and overall health status

Explanation: ***Tumor size, location, liver function, and portal hypertension status*** - **Tumor size and location** are critical for resectability and RFA feasibility, as HCCs larger than 3-5 cm or located near major vessels/bile ducts may be harder to ablate or resect safely. - **Liver function (Child-Pugh A)** helps assess the liver's reserve to tolerate resection, while the presence of **portal hypertension** indicates a higher risk of post-resection liver decompensation, favoring RFA. *Presence of comorbidities and performance status* - While important for overall surgical risk assessment (ASA score), **comorbidities** and **performance status** are general considerations and not the primary factors differentiating between liver resection and RFA for HCC in a patient with good liver function. - These factors influence the patient's ability to undergo any intervention, but they don't directly guide the choice between a local ablative therapy and surgical removal based on tumor or liver characteristics. *Tumor vascular invasion and metastasis* - The presence of **vascular invasion** or **distant metastasis** generally indicates advanced disease, precluding both curative resection and RFA, pushing towards systemic therapies or palliative care. - These are factors that determine if **curative treatment** is an option at all, rather than helping to choose between two curative local treatments (resection vs. RFA). *Patient’s age and overall health status* - **Age** is less of a direct contraindication for either procedure in itself, especially in a 60-year-old with Child-Pugh A, as physiological age and performance status are more relevant than chronological age. - While **overall health status** is considered, it overlaps with comorbidities and performance status and is not as discriminative as tumor-specific factors or liver physiology in choosing between resection and RFA for HCC.

Question 5: Which of the following is the platinum-based chemotherapeutic agent used as first-line treatment for ovarian carcinoma?

A. Cyclophosphamide
B. Methotrexate
C. Cisplatin (Correct Answer)
D. Dacarbazine

Explanation: ***Cisplatin*** - **Cisplatin** is a platinum-based chemotherapy drug that forms **DNA cross-links**, inhibiting DNA synthesis and leading to the death of rapidly dividing cells, making it highly effective against **ovarian carcinoma**. - It is a cornerstone of chemotherapy regimens for ovarian cancer, often used in combination with other agents such as paclitaxel. *Methotrexate* - **Methotrexate** is an **antimetabolite** that inhibits dihydrofolate reductase, thereby interfering with DNA synthesis. - While it is used in various cancers like leukemia, lymphoma, and some solid tumors (e.g., breast cancer, gestational trophoblastic disease), it is **not a primary recommended drug for ovarian carcinoma**. *Cyclophosphamide* - **Cyclophosphamide** is an **alkylating agent** that causes DNA damage, leading to cell death. - It is used in many cancers, including lymphoma, breast cancer, and some leukemias, but it is **not a first-line or primary agent for ovarian carcinoma** in contemporary treatment guidelines. *Dacarbazine* - **Dacarbazine** is an **alkylating agent** primarily used in the treatment of **malignant melanoma** and Hodgkin lymphoma. - It is **not indicated for the treatment of ovarian carcinoma**.

Question 6: A lady presented with a 4 cm tumor in the left parietal lobe for which she underwent surgery and radiotherapy. After 3 months she presented with headache and vomiting. Which of the following would characterize the lesion in the patient?

A. Digital subtraction angiography with dual source CT scan
B. Gd-enhanced MRI
C. 99Tc-HMPAO SPECT brain
D. 18FDG PET Scan (Correct Answer)

Explanation: ***18FDG PET Scan*** - This patient, presenting with new neurological symptoms after **surgery and radiotherapy** for a cerebral tumor, faces a diagnostic dilemma: differentiating between **tumor recurrence** and **radiation necrosis**. - **18FDG PET scans** effectively distinguish between these two conditions because viable tumor cells exhibit high metabolic activity and thus actively take up **fluorodeoxyglucose (FDG)**, while radiation necrosis is metabolically inactive and shows little to no FDG uptake. *Digital subtraction angiography with dual source CT scan* - **Digital subtraction angiography (DSA)** is primarily used to visualize **vascular structures** and is not the modality of choice for differentiating tumor recurrence from radiation necrosis. - A **dual-source CT scan** is useful for rapid imaging and dynamic studies but lacks the metabolic information needed for this specific differentiation. *Gd-enhanced MRI* - While **Gd-enhanced MRI** is excellent for detecting **structural changes** and **blood-brain barrier disruption**, it often cannot definitively differentiate between **tumor recurrence** and **radiation necrosis**. - Both conditions can present with similar **enhancement patterns** on MRI, making differentiation challenging without additional metabolic information. *99Tc-HMPAO SPECT brain* - **99mTc-HMPAO SPECT** measures **regional cerebral blood flow (rCBF)**, which can be altered in both tumors and areas of radiation injury. - However, it does not provide the specific metabolic information (glucose metabolism) needed to reliably distinguish between **viable tumor cells** and **radiation necrosis** as effectively as FDG PET.

Question 7: Gold standard investigation for breast carcinoma screening in a patient with silicone breast implants

A. Mammography
B. CT scan
C. USG
D. MRI (Correct Answer)

Explanation: ***MRI*** - **MRI** is considered the **gold standard** for breast cancer screening in patients with silicone breast implants due to its superior ability to visualize breast tissue through the implant and detect subtle lesions. - It offers **high sensitivity** in detecting both implant rupture and early malignancies, often providing better clarity than mammography in augmented breasts where implants can obscure tissue. *Mammography* - While a standard screening tool, **mammography** can be limited in patients with silicone implants because the implants can **obscure adjacent breast tissue**, making detection of small masses challenging. - Special views (e.g., **Eklund views**) can be used, but sensitivity is still reduced compared to MRI in augmented breasts. *CT scan* - **CT scans** are not routinely used for primary breast cancer screening due to their use of **ionizing radiation** and lower sensitivity for detecting early breast lesions compared to MRI. - CT is more commonly used for **staging** advanced cancers or evaluating complex masses detected by other modalities. *USG* - **Ultrasound (USG)** is a valuable complementary tool, especially for evaluating palpable lumps or clarifying findings from mammography, but it is **operator-dependent** and has a lower overall sensitivity for general screening compared to MRI. - It is particularly useful for differentiating between **cystic and solid masses** and detecting implant ruptures but is not the gold standard for comprehensive screening in augmented breasts.

Question 8: What is the treatment of choice for a post-operative abscess?

A. Hydration
B. IV antibiotics
C. Image guided aspiration (Correct Answer)
D. Reexploration

Explanation: ***Image-guided aspiration*** - This is often the **first-line treatment** for a post-operative abscess, especially if it is well-localized. - It involves **draining the pus** under imaging guidance, relieving pressure and removing the infectious material. *Hydration* - While important for overall patient management, especially in cases of infection or sepsis, **hydration alone does not treat an abscess**. - It is a supportive measure but does not address the **localized collection of pus**. *IV antibiotics* - Antibiotics are typically indicated as an **adjunct to drainage**, especially in cases of systemic infection or cellulitis. - However, **antibiotics alone are often insufficient** to resolve an abscess as they have difficulty penetrating the necrotic core and thick capsule. *Reexploration* - **Surgical reexploration** is a more invasive option usually reserved for abscesses that are **large, multiloculated, not amenable to percutaneous drainage**, or when initial drainage attempts fail. - It carries greater risks and is not the initial treatment of choice for every post-operative abscess.

Question 9: Heat-labile instruments for use in surgical procedures can be best sterilized by what method?

A. Absolute alcohol
B. Ultraviolet rays
C. Chlorine releasing compounds
D. Ethylene oxide gas (Correct Answer)

Explanation: ***Ethylene oxide gas*** - **Ethylene oxide** is a highly effective **sterilizing agent** that can penetrate packaging and is suitable for **heat-sensitive materials** due to its low-temperature application. - It works by **alkylating microbial proteins and nucleic acids**, leading to the death of all microorganisms, including **spores**. *Absolute alcohol* - While **alcohol** is an effective **disinfectant**, it is not a reliable sterilant as it does not consistently kill **bacterial spores**. - Its efficacy as a disinfectant is also limited by its **rapid evaporation** and inability to penetrate organic matter effectively. *Ultraviolet rays* - **UV radiation** is a surface disinfectant and is not suitable for sterilizing surgical instruments as it has **poor penetration** capabilities and cannot sterilize shadowed or covered areas. - It primarily works by damaging the **DNA of microorganisms**, making it effective for air and surface disinfection but not for complex instruments. *Chlorine-releasing compounds* - **Chlorine compounds** are potent disinfectants, but they are often **corrosive to metals** and can damage delicate surgical instruments upon prolonged exposure. - While effective at killing many microorganisms, they are also **not reliably sporicidal** at concentrations safe for instrument sterilization and may leave residues.

Question 10: Best treatment for stage III frostbite is:

A. Rapid rewarming (Correct Answer)
B. Gradual thawing
C. Amputation
D. Immediate surgical debridement

Explanation: ***Rapid rewarming*** - This is the cornerstone of frostbite treatment, regardless of the stage, to minimize **cellular damage** and improve outcomes. - **Rapid rewarming** in a circulating water bath maintained at **37-39°C** is preferred, as it quickly restores tissue perfusion and reduces ice crystal formation. *Gradual thawing* - **Gradual thawing** is less effective than rapid rewarming and can lead to prolonged exposure to cold injury, increasing tissue damage due to continued cellular dehydration and **ice crystal growth**. - It does not provide the rapid restoration of blood flow necessary to prevent further ischemic injury. *Amputation* - **Amputation** is a last resort treatment for severe, irreversible tissue necrosis and is typically performed after the extent of tissue damage is clearly demarcated, often weeks after the initial injury. - It is not an immediate initial treatment for frostbite, even for severe stages, as tissue viability needs to be thoroughly assessed first. *Immediate surgical debridement* - **Immediate surgical debridement** is generally contraindicated in freeze injury because it is often difficult to distinguish viable from non-viable tissue early on. - Early debridement can lead to the unnecessary removal of tissue that might otherwise recover, and surgical intervention is usually delayed until demarcation is clear, typically weeks later.

Want unlimited practice?

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

Start For Free