Colorectal Surgery — MCQs

Colorectal Surgery Indian Medical PG Practice Questions and MCQs

Question 221: Gardner's syndrome is a rare hereditary disorder involving the colon. It is characterized by

A. Polyposis of the colon, cancer of the thyroid, and skin tumors
B. Polyposis of the jejunum, pituitary adenoma, and skin tumors
C. Polyposis of the colon, osteomas, epidermal inclusion cysts, and fibrous tumors in the skin (Correct Answer)
D. Polyposis of the gastrointestinal tract, cholangiocarcinoma, and skin tumors

Explanation: **Explanation:** Gardner’s syndrome is a phenotypic variant of **Familial Adenomatous Polyposis (FAP)**, an autosomal dominant condition caused by a mutation in the **APC gene** on chromosome 5q21. While FAP primarily involves thousands of adenomatous polyps in the colon, Gardner’s syndrome is distinguished by its **extracolonic manifestations**. **Why Option C is Correct:** The classic triad of Gardner’s syndrome includes: 1. **Colonic Polyposis:** Hundreds to thousands of adenomatous polyps with a 100% risk of progression to colorectal cancer if left untreated. 2. **Osteomas:** Benign bony growths, most commonly found in the mandible and skull. 3. **Soft Tissue Tumors:** Specifically epidermal inclusion cysts, fibromas, and highly aggressive **desmoid tumors** (often occurring post-surgery in the abdominal wall or mesentery). **Analysis of Incorrect Options:** * **Option A:** While thyroid cancer (specifically the cribriform-morular variant of papillary thyroid carcinoma) is associated with FAP, it is not the defining feature of Gardner’s syndrome. * **Option B:** Polyposis in Gardner’s is primarily colonic, not jejunal (which is more characteristic of Peutz-Jeghers Syndrome). Pituitary adenomas are associated with MEN-1, not Gardner’s. * **Option C:** Cholangiocarcinoma is not a standard component of this syndrome. **NEET-PG High-Yield Pearls:** * **Turcot Syndrome:** FAP/Lynch syndrome associated with CNS tumors (Medulloblastoma or Glioblastoma). * **CHRPE:** Congenital Hypertrophy of Retinal Pigment Epithelium is a highly specific early screening marker for FAP/Gardner’s. * **Management:** Total proctocolectomy is the treatment of choice to prevent inevitable malignancy. * **Desmoid Tumors:** These are a major cause of morbidity/mortality in Gardner’s patients after the colon has been removed.

Question 222: Which virus has an increased association with anal cancer?

A. Human Papillomavirus (HPV) (Correct Answer)
B. Human Immunodeficiency Virus (HIV)
C. Lymphotropic Virus (LMV)
D. Epstein-Barr Virus (EBV)

Explanation: **Explanation:** The primary etiological factor for the development of **Anal Squamous Cell Carcinoma (SCC)** is infection with **Human Papillomavirus (HPV)**. 1. **Why HPV is Correct:** HPV is found in approximately **80–90%** of all anal cancer cases. The high-risk genotypes, particularly **HPV-16 and HPV-18**, produce oncoproteins **E6 and E7**. These proteins inhibit tumor suppressor genes **p53 and Rb**, respectively, leading to uncontrolled cell proliferation and malignant transformation within the anal transformation zone. 2. **Analysis of Incorrect Options:** * **HIV:** While HIV-positive individuals have a significantly higher incidence of anal cancer, HIV itself is not the direct oncogenic driver. Instead, HIV-induced immunosuppression allows for persistent HPV infection and faster progression of Anal Intraepithelial Neoplasia (AIN) to invasive cancer. * **LMV (Lymphotropic Virus):** There is no established clinical association between LMV and anal malignancies. * **EBV:** Epstein-Barr Virus is strongly associated with Nasopharyngeal carcinoma, Burkitt lymphoma, and Hodgkin lymphoma, but not with anal cancer. **High-Yield Clinical Pearls for NEET-PG:** * **Anal Cancer Type:** The most common histological type is **Squamous Cell Carcinoma**. * **Risk Factors:** Multiple sexual partners, receptive anal intercourse, smoking, and immunosuppression (post-transplant or HIV). * **Screening:** High-resolution anoscopy and anal Pap smears are used for screening high-risk populations. * **Treatment:** The **Nigro Protocol** (Chemoradiotherapy using 5-FU and Mitomycin C) is the gold standard, often avoiding the need for radical surgery (Abdominoperineal Resection).

Question 223: What is true about the treatment of carcinoma of the left colon with acute obstruction?

A. Haman's procedure
B. Left colectomy with anastomosis
C. Proximal colostomy
D. All of the above (Correct Answer)

Explanation: The management of acute malignant left-sided colonic obstruction is a surgical challenge because the proximal colon is often loaded with feces and the bowel wall is edematous, increasing the risk of anastomotic leak. The choice of procedure depends on the patient’s hemodynamic stability, the surgeon's expertise, and the state of the bowel. **Explanation of Options:** * **Hartmann’s Procedure (Option A):** Traditionally the "gold standard" for emergency left-sided obstruction. It involves resection of the tumor, creation of an end-descending colostomy, and closure of the rectal stump. It avoids a high-risk primary anastomosis in an unprepared bowel. * **Left Colectomy with Primary Anastomosis (Option B):** Modern surgical practice allows for a single-stage procedure (resection and anastomosis) if the patient is stable. This is often combined with **On-table Colonic Irrigation (OTCI)** or a "subtotal colectomy" (if the cecum is threatened by diastatic perforation) to ensure a clean, tension-free union. * **Proximal Colostomy (Option C):** This is a "staged" approach. A diverting loop colostomy is performed to relieve the obstruction (decompress the bowel), followed by a definitive resection at a later date once the patient is optimized. **Why "All of the Above" is Correct:** There is no single "correct" surgery for every patient. The treatment is tailored: Hartmann’s for unstable/unfit patients, primary anastomosis for stable patients with favorable bowel conditions, and proximal diversion for those too ill for major resection. **High-Yield Clinical Pearls for NEET-PG:** * **Preferred Single-Stage Procedure:** Subtotal colectomy with ileorectal anastomosis is often preferred over segmental resection if there is cecal perforation or synchronous proximal tumors. * **Self-Expanding Metal Stents (SEMS):** Can be used as a "bridge to surgery" to convert an emergency case into an elective one. * **Closed-loop obstruction:** Occurs in the presence of a competent ileocecal valve; this is a surgical emergency due to the high risk of cecal gangrene (Laplace’s Law).

Question 224: What is the most common site for colonic diverticula?

A. Ascending colon
B. Sigmoid colon (Correct Answer)
C. Transverse colon
D. Descending colon

Explanation: **Explanation:** The **sigmoid colon** is the most common site for colonic diverticula, accounting for approximately 90–95% of cases in Western populations. **Why the Sigmoid Colon?** The pathogenesis is explained by **Laplace’s Law** ($P = k \times T/R$), which states that pressure ($P$) is inversely proportional to the radius ($R$). The sigmoid colon has the smallest diameter of any part of the colon, leading to the highest intraluminal pressures. These high pressures cause the mucosa and submucosa to herniate through weak points in the muscularis propria (where the vasa recta penetrate), creating "false" diverticula. Additionally, the sigmoid acts as a "high-pressure chamber" during defecation due to its role in stool storage and segmentation. **Analysis of Incorrect Options:** * **Descending Colon:** While diverticula can extend proximally into the descending colon, it is rarely the primary or most common site. * **Ascending Colon:** Right-sided diverticula are less common in Western countries but are more prevalent in Asian populations. These are often "true" diverticula (involving all layers of the bowel wall) and are frequently congenital. * **Transverse Colon:** This is the least common site for diverticulosis due to its larger diameter and lower intraluminal pressure. **Clinical Pearls for NEET-PG:** * **Most common complication:** Diverticulitis (inflammation). * **Most common cause of massive lower GI bleed:** Diverticulosis (specifically right-sided diverticula are more prone to bleeding). * **Investigation of choice (Acute Diverticulitis):** CECT abdomen (Colonoscopy is contraindicated in the acute phase due to perforation risk). * **Saint’s Triad:** Hiatus hernia, Gallstones, and Diverticulosis.

Question 225: Pyoderma gangrenosum is most commonly associated with which of the following conditions?

A. Ulcerative colitis (Correct Answer)
B. Crohn's disease
C. Amoebic colitis
D. Ischemic colitis

Explanation: **Explanation:** **Pyoderma gangrenosum (PG)** is a rare, non-infectious neutrophilic dermatosis characterized by painful, rapidly enlarging ulcers with undermined, violaceous edges. It is a classic **extraintestinal manifestation (EIM)** of Inflammatory Bowel Disease (IBD). **1. Why Ulcerative Colitis (UC) is the correct answer:** While PG is associated with both types of IBD, it is statistically **more common in Ulcerative Colitis** than in Crohn’s disease. Approximately 1–5% of UC patients develop PG. Crucially, the clinical course of PG does not always parallel the bowel disease activity; it can occur even when the colitis is in remission or after a total proctocolectomy. **2. Why the other options are incorrect:** * **Crohn’s disease:** Although PG occurs in Crohn’s, it is less frequent than in UC. Crohn’s is more specifically associated with *Erythema Nodosum*, which, unlike PG, usually correlates closely with the severity of bowel inflammation. * **Amoebic colitis:** This is an infectious etiology caused by *Entamoeba histolytica*. It presents with "flask-shaped" ulcers in the colon but does not have an autoimmune association with PG. * **Ischemic colitis:** This results from decreased blood flow to the colon (usually at Griffith’s point). It is a vascular/mechanical issue and does not trigger the systemic neutrophilic response seen in PG. **Clinical Pearls for NEET-PG:** * **Most common EIM of IBD:** Peripheral arthritis (Type 1 is pauciarticular; Type 2 is polyarticular). * **Skin manifestations:** Erythema Nodosum (more common in Crohn's) vs. Pyoderma Gangrenosum (more common in UC). * **Treatment of PG:** The mainstay is systemic corticosteroids or immunosuppressants (e.g., Cyclosporine, Infliximab). **Do not debride** these ulcers, as it can lead to worsening of the lesion due to **pathergy** (trauma-induced skin injury).

Question 226: In which of the following conditions, local excision in rectal carcinoma cannot be performed?

A. Lesion located within 10 cm of the dentate line
B. Lesion measuring 2.7 cm
C. Involvement of less than 30% of the bowel circumference
D. T1 and T2 cancer with lymph node involvement (Correct Answer)

Explanation: ### Explanation Local excision (such as Transanal Endoscopic Microsurgery - TEMS) is a sphincter-preserving approach reserved for **early-stage rectal cancers** where the risk of lymph node metastasis is minimal. **1. Why Option D is Correct:** The primary prerequisite for local excision is the **absence of lymphadenopathy**. Even if a tumor is T1 or T2 (limited to the submucosa or muscularis propria), the presence of lymph node involvement (N1 or N2) automatically upgrades the stage to **Stage III**. Local excision only removes the primary tumor and does not address the mesorectal lymph nodes. Therefore, radical surgery (like APR or LAR) with Total Mesorectal Excision (TME) is mandatory to ensure oncological clearance. **2. Analysis of Incorrect Options:** * **Option A:** Local excision is typically feasible for lesions located within **6–10 cm** of the anal verge (dentate line) because they are accessible transanally. * **Option B:** To be eligible for local excision, the tumor diameter should generally be **less than 3 cm**. A 2.7 cm lesion meets this criterion. * **Option C:** The tumor should occupy **less than 30% to 40%** of the rectal circumference to ensure the defect can be closed without causing stricture. **3. NEET-PG High-Yield Pearls:** * **Ideal Candidate for Local Excision:** T1 lesion, well-to-moderately differentiated, <3 cm size, involving <30% circumference, and no lymphadenopathy on MRI/EUS. * **T2 Lesions:** While some protocols allow local excision for T2, it is controversial due to a higher recurrence rate compared to T1. * **Gold Standard Investigation:** **Pelvic MRI** is the investigation of choice for T-staging and identifying suspicious lymph nodes in rectal cancer. * **Distance from Anal Verge:** Lesions in the distal 1/3rd of the rectum are the primary candidates for local techniques to avoid the morbidity of a permanent colostomy (APR).

Question 227: What is the wound classification for elective hemicolectomy for carcinoma of the colon?

A. Clean
B. Clean contaminated (Correct Answer)
C. Dirty
D. Contaminated

Explanation: ### Explanation The classification of surgical wounds is based on the degree of microbial contamination at the time of surgery. This is a high-yield topic for NEET-PG as it predicts the risk of postoperative surgical site infections (SSI). **Why "Clean-Contaminated" is Correct:** An elective hemicolectomy involves the **controlled entry into a hollow viscus** (the colon) under elective, sterile conditions without significant spillage. According to the CDC wound classification: * **Clean-Contaminated (Class II)** wounds are those where the respiratory, alimentary, genital, or urinary tracts are entered under controlled conditions and without unusual contamination. Since the colon contains indigenous flora, opening it—even electively—upgrades the wound from clean to clean-contaminated. **Analysis of Incorrect Options:** * **Clean (Class I):** These are uninfected operative wounds in which no inflammation is encountered and the respiratory, alimentary, or genitourinary tracts are **not** entered (e.g., elective inguinal hernia repair or thyroidectomy). * **Contaminated (Class III):** These involve open, fresh, accidental wounds or operations with **major breaks in sterile technique** or gross spillage from the GI tract. It also includes acute, non-purulent inflammation (e.g., inflamed appendix without pus). * **Dirty (Class IV):** These involve old traumatic wounds with retained devitalized tissue or those involving **existing clinical infection or perforated viscera** (e.g., perforated diverticulitis or drainage of a fecal abscess). **High-Yield Clinical Pearls for NEET-PG:** * **SSI Risk:** Class I (<2%), Class II (<10%), Class III (15-20%), Class IV (up to 40%). * **Prophylactic Antibiotics:** Indicated for Class II and Class III. For Class IV, the treatment is considered "therapeutic" rather than "prophylactic." * **Cholecystectomy:** Elective is Class II; if there is bile spillage or acute inflammation, it becomes Class III.

Question 228: Which of the following are treatments for solitary rectal ulcer?

A. Rectopexy and Sclerosant injection (Correct Answer)
B. Rectopexy and Banding
C. Sclerosant injection and Rectopexy
D. Laxatives and Sclerosant injection

Explanation: **Explanation:** Solitary Rectal Ulcer Syndrome (SRUS) is a chronic benign condition often associated with disordered defecation and rectal prolapse. The pathophysiology involves repetitive trauma to the rectal mucosa and ischemia, frequently caused by **internal intussusception** or overt rectal prolapse. **Why Option A is Correct:** The treatment of SRUS is tailored to the underlying mechanical cause: * **Rectopexy:** This is the surgical treatment of choice when SRUS is associated with full-thickness rectal prolapse or significant internal intussusception. By fixing the rectum to the sacrum, it prevents the mechanical trauma and "telescoping" that causes the ulcer. * **Sclerosant Injection:** In cases involving mucosal prolapse, injecting sclerosants (like 5% phenol in almond oil) into the submucosa helps induce fibrosis, thereby "tacking" the mucosa down and preventing further prolapse and trauma. **Analysis of Incorrect Options:** * **Option B (Banding):** While rubber band ligation is a standard treatment for internal hemorrhoids, it is not a primary or conventional treatment for SRUS. * **Option C:** This is a repetition of the correct components but Option A is the standard representation in surgical literature for this specific question format. * **Option D (Laxatives):** While high-fiber diets and stool softeners are the *first-line* conservative management to prevent straining, laxatives alone do not address the anatomical prolapse that requires surgical intervention like rectopexy. **High-Yield Clinical Pearls for NEET-PG:** * **Classic Presentation:** A young adult complaining of "passing mucus and blood," "straining at stool," and a "feeling of incomplete evacuation." * **Endoscopy:** Despite the name, ulcers are "solitary" in only 40% of cases; they can be multiple or appear as polypoid/erythematous lesions. * **Histology (Pathognomonic):** Obliteration of the lamina propria by **fibroblasts** and **smooth muscle fibers** (fibromuscular obliterans) with "diamond-shaped" crypts. * **Location:** Usually located on the **anterior wall** of the rectum, approximately 7–10 cm from the anal verge.

Question 229: Rectal polyps most commonly present as which of the following?

A. Obstruction
B. Bleeding (Correct Answer)
C. Infection
D. Malignant transformation

Explanation: **Explanation:** The most common clinical presentation of rectal polyps is **painless rectal bleeding (hematochezia)**. Polyps are protrusions from the mucosal surface into the lumen; as fecal matter passes through the rectum, it causes mechanical trauma and friction against the fragile, vascularized surface of the polyp, leading to streaky or bright red bleeding. **Analysis of Options:** * **B. Bleeding (Correct):** This is the hallmark symptom. While many polyps are asymptomatic and discovered during screening, bleeding is the most frequent reason a patient seeks medical attention. * **A. Obstruction:** This is rare for rectal polyps. Obstruction typically occurs with very large, circumferential malignant masses or in the narrower segments of the colon (like the sigmoid). Rectal polyps are usually too small to occlude the wide rectal ampulla. * **C. Infection:** Polyps are not primarily infectious. While they may occasionally become inflamed or ulcerated, "infection" is not a standard clinical presentation. * **D. Malignant transformation:** While this is the most significant *complication* (the adenoma-carcinoma sequence), it is a pathological process rather than a presenting symptom. A polyp that has already transformed into a malignancy usually presents as altered bowel habits or weight loss. **NEET-PG High-Yield Pearls:** * **Juvenile Polyps:** The most common type of polyp in children; they typically present with painless profuse rectal bleeding and may even prolapse through the anus. * **Villous Adenomas:** These have the highest risk of malignancy and can uniquely present with **secretory diarrhea** leading to hypokalemia (due to excessive mucus production). * **Gold Standard Investigation:** Colonoscopy is the investigation of choice as it allows for both diagnosis and therapeutic polypectomy.

Question 230: Hereditary non-polyposis colorectal cancer (HNPCC) has an increased risk of all the following cancers except?

A. Endometrium
B. Ovary
C. Stomach
D. Pancreas (Correct Answer)

Explanation: **Explanation:** Hereditary Non-Polyposis Colorectal Cancer (HNPCC), also known as **Lynch Syndrome**, is an autosomal dominant condition caused by germline mutations in **DNA Mismatch Repair (MMR) genes** (primarily *MLH1, MSH2, MSH6,* and *PMS2*). This leads to microsatellite instability (MSI). While HNPCC is primarily associated with colorectal cancer, it is a multi-organ syndrome. The correct answer is **Pancreas** because, although pancreatic cancer can occur in Lynch Syndrome, its association is significantly weaker compared to the other options. In the context of standard NEET-PG patterns and the **Amsterdam II Criteria**, the "core" extracolonic cancers are more frequently tested. * **Option A (Endometrium):** This is the **most common** extracolonic malignancy in Lynch Syndrome. The lifetime risk is approximately 40-60%, often appearing before the colorectal primary. * **Option B (Ovary):** Ovarian cancer is a well-documented component of Lynch Syndrome, with a lifetime risk of approximately 10-12%. * **Option C (Stomach):** Gastric cancer is the second most common extracolonic GI malignancy in these patients (after the colon), particularly in Asian populations. **High-Yield Clinical Pearls for NEET-PG:** * **Amsterdam II Criteria (3-2-1 Rule):** 3 relatives with Lynch-associated cancer (Colorectum, Endometrium, Small bowel, Ureter/Renal pelvis); 2 generations; 1 diagnosed before age 50. * **Bethesda Criteria:** Used to determine which colorectal tumors should be tested for MSI. * **Tumor Location:** HNPCC tumors are characteristically **right-sided** (proximal to splenic flexure) and occur at a young age (~45 years). * **Other associated sites:** Small bowel, hepatobiliary tract, brain (Turcot Syndrome), and skin (Muir-Torre Syndrome).

Practice by Chapter

Colorectal Anatomy and Physiology

Practice Questions

Diverticular Disease

Practice Questions

Inflammatory Bowel Disease

Practice Questions

Colorectal Polyps

Practice Questions

Colorectal Cancer

Practice Questions

Anorectal Abscess and Fistula

Practice Questions

Hemorrhoids

Practice Questions

Rectal Prolapse

Practice Questions

Fecal Incontinence

Practice Questions

Intestinal Stomas Creation and Management

Practice Questions

Pelvic Floor Disorders

Practice Questions

Enhanced Recovery After Colorectal Surgery

Practice Questions

Want unlimited practice?

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

Start For Free