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Free STEP3 Exam Braindumps (page: 69)

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A 46-year-old female presents to your office with rectal bleeding, itching, and irritation. On examination, a 3-cm ulcerating lesion is seen in the anal canal. Biopsy of the lesion reveals squamous cell carcinoma (SCC). Which of the following is the most appropriate treatment?

  1. chemotherapy and pelvic radiation protocol
  2. low anterior resection
  3. abdominal perineal resection
  4. wide local excision of the lesion
  5. wide local excision of the lesion and bilateral inguinal lymph node dissection

Answer(s): A

Explanation:

Anal carcinoma can arise from several epithelial cell types in the anal canal including squamous, basaloid, cloacogenic, and mucoepidermoid. For early, superficial lesions less than 2 cm, an attempt can be made to excise the lesion completely with negative margins. Otherwise, the standard of care is a multimodality chemoradiation protocol, which classically includes itomycin C and 5-FU in combination with external beam radiation therapy to the tumor and the pelvic and inguinal lymph nodes. The long-term survival rate after chemoradiation alone compares favorably with radical surgery. Abdominal perineal resection is reserved for persistent or recurrent disease. Low anterior resection refers to resection of the upper and middle rectum and plays no role in the treatment of anal cancer. Inguinal lymph node dissection is not indicated. Any clinically suspicious node should be biopsied, and if positive, treated with radiation. Thus, even a small anal cancer with a positive lymph node should be treated with chemotherapy instead of surgery.



During initial exploration in a patient scheduled to undergo a right hemicolectomy for colon cancer, a deep 4-cm liver mass is seen in the right lobe of the liver. The left lobe appears to be normal. Intraoperative biopsy of the lesion is positive for metastatic colon cancer. The best management of this patient includes which of the following?

  1. Immediately close the patient and refer for chemotherapy only.
  2. Perform right hemicolectomy only.
  3. Perform right hemicolectomy and right hepatic lobectomy.
  4. Perform right hemicolectomy and wide excision of the liver lesion.
  5. Perform liver resection only.

Answer(s): B

Explanation:

Colon cancer is the most common metastatic lesion of the GI tract to the liver. Approximately 50% of patients with colorectal cancer will have liver involvement. Generally, synchronous liver metastasis should not be resected during the initial operation for the primary tumor. Only a solitary, small, peripherally located lesion in a hemodynamically stable patient would be an acceptable indication for a wedge resection. Otherwise, the planned colon resection should be completed. A second procedure can be planned after a thorough metastatic evaluation is completed using various diagnostic modalities such as intraoperative ultrasound, CT, MRI, and/or PET scan. A delay of weeks to months between surgeries has not been shown to have a negative impact on long-term survival. The delay may help select patients who may benefit the most and exclude those who develop widespread metastatic disease during the interval. Chemotherapy only is inappropriate because, even in the presence of metastatic disease, the primary colon carcinoma should be resected to prevent later complications such as bleeding, perforation, or obstruction. The 5-year survival rate following resection of isolated hepatic metastasis from colorectal cancer now exceeds 50%.



A mobile mass is found on rectal examination in a 77-year-old male with complaints of blood in his stool. On workup, he is found to have a stage I (Dukes' A), well-differentiated adenocarcinoma. The most appropriate intervention is which of the following?

  1. transanal excision
  2. abdominal perineal resection
  3. low anterior resection
  4. placement of endorectal wallstent
  5. neoadjuvant chemotherapy followed by transanal resection

Answer(s): A

Explanation:

Local treatment of rectal cancer is the treatment of choice in selected individuals with low-lying rectal cancers. The lesion must be mobile, nonulcerated, within 10 cm of the anal verge, less than 3 cm in diameter, less that onefourth the circumference of the rectal wall, and stage T1 or T2 on endorectal ultrasound. Transanal excision is the most straightforward technique of local treatment. It entails full thickness excision of the lesion into the perirectal fat with adequate margins. For early lesions into the submucosa only (T1), no adjuvant therapy is required unless poor prognostic features are present on final pathology (poorly differentiated or lymphatic/vascular invasion). If the lesion penetrates the muscular wall (T2), adjuvant radiation therapy with or without chemotherapy is indicated following surgical removal.
Overall, the disease free survival rate is 80%.



A27-year-old female whose father had a colon resection for adenocarcinoma undergoes her first colonoscopy. Over 100 small polyps are seen distributed mainly in her sigmoid and rectum. Multiple polyps are removed and histologic review reveals tubular adenomas with no evidence of atypia or dysplasia. The most appropriate next step in her management is which of the following?

  1. total proctocolectomy with ileoanal J pouch reconstruction
  2. surveillance colonoscopy in 5 years
  3. surveillance colonoscopy every 2 years until all polyps are removed
  4. flexible sigmoidoscopy with representative biopsy every 6 months for 2 years, then yearly for 3 years, then every 35 years
  5. abdominal perineal resection with sigmoid resection and end colostomy

Answer(s): A

Explanation:

The patient described has familial adenomatous polyposis (FAP). FAP is a rare autosomal dominant inherited form of colorectal cancer that results from a germline mutation in the APC gene. The disease is characterized by the presence of >100 polyps in the large intestine, as well as extraintestinal manifestations such as epidermoid cysts, desmoid tumors, and osteomas. All patients with FAP will develop colorectal cancer if left untreated. The average age of diagnosis is 29 and the average age of the development of cancer is 39. Once diagnosed, the most definitive treatment requires complete removal of the entire colon and rectum in a timely fashion. Surveillance colonoscopy is not protective against the development of cancer regardless of the frequency. The surgical procedure of choice is a proctocolectomy with permanent ileostomy or creation of an ileoanal anastomosis with ileal reservoir such as a J-pouch. Abdominal perineal resection with sigmoid colectomy leaves a significant portion of colon in situ with subsequent risk of developing colon cancer.






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