What is the best investigation for a male patient with a history of right hemicolectomy for colonic cancer (T1a, N0, M0) presenting with right lower quadrant pain, weight loss, and constipation?

From the Guidelines

The best investigation for a male patient with a history of right hemicolectomy for colonic cancer (T1a, N0, M0) presenting with right lower quadrant pain, weight loss, and constipation is a contrast-enhanced CT scan of the abdomen and pelvis, accompanied by measurement of carcinoembryonic antigen (CEA) levels and colonoscopy to directly visualize the anastomotic site and remaining colon. This approach is based on the guidelines for surveillance after colon cancer treatment, which recommend regular monitoring for recurrence, especially in the first few years after surgery 1. The patient's symptoms, such as right lower quadrant pain, weight loss, and constipation, are concerning for possible recurrence, and a prompt evaluation with imaging and tumor marker assessment is necessary. The CT scan should be performed with IV and oral contrast, and if there are any contraindications to CT with IV contrast, consider abdominal/pelvic MRI with MRI contrast plus a non-contrast chest CT 1. Additionally, colonoscopy should be performed to rule out local recurrence or metachronous lesions, as recommended by the guidelines for colonoscopy surveillance after cancer resection 1. It is essential to note that PET-CT scan is not routinely recommended for surveillance outside of a clinical trial 1, but it may be considered if the CT scan is negative and symptoms persist, due to its higher sensitivity for detecting small volume recurrent disease. Early detection of recurrence is crucial, as it may still be amenable to curative surgical resection, and the patient's quality of life and survival outcomes can be significantly improved with prompt and appropriate management. The guidelines emphasize the importance of individualized follow-up care, taking into account the patient's risk of recurrence, functional status, and preferences 1. In this case, given the patient's history and symptoms, a comprehensive evaluation with CT scan, CEA measurement, and colonoscopy is the most appropriate initial step.

From the Research

Best Investigation for Male Patient with History of Right Hemicolectomy

The patient presents with right lower quadrant pain, weight loss, and constipation, which could be indicative of a recurrence of colonic cancer or other complications.

• The most suitable investigation would be one that can accurately detect and stage any potential recurrence or metastasis.
• Considering the patient's history of colonic cancer, a diagnostic tool that can provide both anatomical and functional information would be ideal.
• Among the options provided, B. Abdominal CECT and C. PET are the most relevant investigations for this scenario.

Rationale for Choice

• Abdominal CECT is useful for detecting structural changes and can help identify any local recurrence or metastasis in the abdomen 2, 3.
• PET, specifically FDG PET/CT, has been shown to improve the sensitivity and specificity in detecting malignant disease, including recurrence and metastasis, especially in patients with a history of cancer 4.
• PET/CT can also assess early metabolic response to treatment, which can aid in treatment decisions and provide prognostic information 4.
• While Colonoscopy is crucial for surveillance in patients with a history of colonic cancer, it may not directly address the current symptoms of right lower quadrant pain, weight loss, and constipation.
• US and MRI can be useful in specific scenarios but are not the primary choice for this patient's presentation.

Considerations

• The choice between Abdominal CECT and PET/CT may depend on the availability of resources, the patient's overall condition, and specific clinical suspicions.
• PET/CT is particularly useful when there is suspicion of recurrent or residual disease, especially in patients with distorted anatomy from surgery or radiotherapy 4.