Pathological Complete Response in Rectal Cancer Patients: A Correlation Between Pathological and Clinical Stage and...

Area of Science:

• Oncology
• Radiology
• Surgical Oncology

Background:

• Treatment strategies for rectal cancer are guided by tumor stage and neoadjuvant therapy response.
• Accurate assessment of tumor regression via MRI can inform personalized management, including nonoperative approaches.
• Predicting pathological complete response (pCR) is crucial for optimizing rectal cancer treatment.

Purpose of the Study:

• To evaluate the correlation between clinical staging and pathological complete response (pCR) in rectal cancer patients.
• To assess the accuracy of MRI in determining tumor response after neoadjuvant therapy.
• To explore associations between pCR and clinical variables in rectal cancer.

Main Methods:

• Retrospective analysis of 1693 rectal cancer patients treated with neoadjuvant therapy and radical resection.
• Clinical staging and tumor response assessed using MRI, focusing on T- and N-stage.
• pCR defined as absence of tumor cells on histopathology; associations with clinical variables explored.

Main Results:

• Of 783 patients receiving neoadjuvant therapy, 62 (7.92%) achieved pCR.
• Pre-treatment stages were predominantly cT3 and cN2b.
• Post-treatment MRI showed complete tumor response (T0) in 32.3% and nodal downstaging to N0 in 54.8% of patients.
• MRI demonstrated limited correlation between clinical assessment and pathological outcome; 9.6% developed distant metastases, with no local recurrences.

Conclusions:

• MRI is valuable for preoperative assessment but has limited accuracy in predicting pCR for rectal cancer.
• pCR is a positive prognostic indicator but does not negate the risk of distant metastasis.
• Individualized surveillance and management are essential for optimizing outcomes in rectal cancer patients who achieve pCR.