Pathological and Oncologic Outcomes of Consolidation Chemotherapy in Locally Advanced Rectal Cancer after Neoadjuvant Chemoradiation

Abstract

Objective: The current standard of care for locally advanced rectal cancer is associated with multimodality therapy. Neoadjuvant chemoradiation significantly decreased the locoregional recurrence rate and improved survival. However, distant metastasis develops rather than local recurrence, which becomes the leading cause of death. This study aimed to evaluate the oncological outcomes of total neoadjuvant therapy (TNT) in locally advanced rectal cancer. Materials and Methods: This retrospective study recruited 18 patients diagnosed with locally advanced rectal adenocarcinoma (cT3-4 or cN1-2), treated with consolidation TNT. The primary endpoint was pathological complete response (pCR). The secondary endpoint included postoperative outcomes, local recurrences, and distant metastases. Results: The pathologic complete response was observed in 27.8% of consolidation therapy cases. Downstaging of the T-category was achieved in 10 (55.6%) patients, and downstaging of the N-category was achieved in 14 (77.8%) patients. Only one patient who achieved pCR developed distant metastasis, whereas all patients with pathological stage III developed distant metastasis. Conclusions: TNT is a promising approach for patients with locally advanced rectal cancer. This strategy improved complete pathologic response rates in TNT, and pCR was found to be associated with fewer local recurrences and greater disease-free survival.

Keywords

• Consolidation
• induction chemotherapy
• total neoadjuvant therapy
• rectal cancer
• pathologic complete response