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 early-stage colon cancer (T1a, N0, M0) who presents with right lower quadrant pain, weight loss, and constipation is a contrast-enhanced CT scan of the abdomen and pelvis, along with colonoscopy. This recommendation is based on the most recent and highest quality study available, which emphasizes the importance of comprehensive evaluation for cancer recurrence and other potential causes of symptoms in patients with a history of colorectal cancer 1.

Key Considerations

• The patient's symptoms, including right lower quadrant pain, weight loss, and constipation, raise concern for cancer recurrence or complications following colorectal surgery.
• A contrast-enhanced CT scan of the abdomen and pelvis can detect local recurrence, metastatic disease, anastomotic complications, or other abdominal pathologies that might explain the concerning symptoms.
• Colonoscopy allows direct visualization of the anastomotic site and remaining colon to identify recurrent tumors, strictures, or inflammatory changes.
• Blood tests, including complete blood count, liver function tests, and carcinoembryonic antigen (CEA) levels, should also be performed to assess for anemia, metastatic disease, and tumor marker elevation.

Evidence-Based Recommendations

• The Chinese Society of Clinical Oncology (CSCO) guidelines recommend follow-up with contrast-enhanced CT scan of the abdomen and pelvis, along with colonoscopy, for patients with a history of colorectal cancer 1.
• The guidelines also emphasize the importance of physical examination, blood CEA testing, and liver ultrasound examination in the follow-up of patients with colorectal cancer.
• PET/CT is not recommended as a routine follow-up tool, but may be considered in cases of clinical suspicion of recurrence with negative routine imaging 1.

Clinical Implications

• The combination of contrast-enhanced CT scan and colonoscopy provides a comprehensive evaluation for cancer recurrence and other potential causes of symptoms in patients with a history of colorectal cancer.
• The patient's symptoms and history warrant thorough investigation, despite the initially favorable pathology, as they align with potential recurrence patterns or complications following colorectal surgery.
• The recommended investigations are particularly important in the context of real-life clinical medicine, where the goal is to prioritize morbidity, mortality, and quality of life outcomes.

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 malignant disease, assess the extent of disease, and guide treatment decisions.
• Considering the patient's history of colonic cancer, a diagnostic tool that can detect metabolic changes in the body would be beneficial.
• Positron Emission Tomography Computed Tomography (PET-CT) is a functional imaging modality that has improved sensitivity and specificity in detecting malignant disease 2.
• PET-CT can assess early metabolic response to treatment, aid in treatment decisions, and provide important prognostic information.
• It is also helpful in patients with distorted anatomy from surgery or radiotherapy when there is suspicion of recurrent or residual disease.

Comparison of Diagnostic Tools

Other diagnostic tools such as Contrast-Enhanced Computed Tomography (CECT) and Non-Contrast-Enhanced Computed Tomography (NECT) can also be used to detect liver metastases and other abdominal pathologies.

• However, studies have shown that the addition of NECT to CECT does not significantly improve the characterization of hypervascular liver metastases or incidental renal and adrenal lesions 3.
• CECT has been compared to NECT and abdominal ultrasound (US) for the detection of hepatic metastasis in breast cancer patients, and the results show that NECT + US has similar diagnostic performance and confidence to CECT 4.
• Contrast-Enhanced Ultrasound (CEUS) has also been compared to PET-CT in lymphoma diagnosis, and the results show that CEUS parameters are correlated with PET-CT values, with potential use in lymphoma diagnosis 5.

Recommended Investigation

Based on the patient's history and presenting symptoms, the best investigation would be:

• B. Abdominal CECT: to assess the extent of disease and detect any potential complications.
• Alternatively, PET-CT (option C) could be considered, especially if there is suspicion of recurrent or residual disease, as it can provide valuable information on metabolic activity and guide treatment decisions 2.