Lack of Pathological Response of Rectal Cancer to Neoadjuvant Chemoradiotherapy is Associated with Poorer Long-Term Oncological Outcomes

Author Info

Debora Kidron Lauren Lahav Liron Berkovich Moshe Mishaeli Nasreen Haj Yahya Shmuel Avital

Corresponding Author

Shmuel Avital
Department of Surgery B, Meir Medical Center, Kfar Saba, Israel

A B S T R A C T

Purpose: Tumor regression scores are used to evaluate local response to preoperative treatment. Complete pathological response (tumor regression score=0) is associated with excellent prognosis. In this study we evaluated the prevalence and impact of poor-to-no pathological response to neoadjuvant treatment (tumor regression score=3), based on a recently revised grading system on long term oncologic outcomes among rectal cancer patients. Methods: This retrospective study included rectal cancer patients who received. neoadjuvant chemoradiotherapy and surgical resection at our medical center. Pathological specimens were ren evaluated and graded (grades 0-3) based on the revised tumor regression scores. Disease free survival and cancer specific survival rates were documented and matched with the patients’ tumor regression scores. Results: Initially 78 patients were included. 6 patients were later excluded from the long-term follow up since they developed disease progression during neoadjuvant treatment. Among the other 72 patients, 38 (52.8%) were classified as tumor regression score=3 (no response) and 34 (47.2%) tumor regression score=0-2 (any level of response). Conversion from laparoscopy to open surgery was higher in the tumor regression score=3 group (21% vs. 2.9%, p=0.02). Follow-up ranged from 5 months to 12 years. Nine (12.5%) patients experienced disease recurrence, 8 with tumor regression score=3. Most recurrences were metastases to liver and lungs. Disease free survival was lower in tumor regression score=3 patients as compared to tumor regression score=0-2. Conclusions: Non-responders to neoadjuvant therapy are at higher risk for disease recurrence, conversion to open surgery and disease-related mortality. Systemic recurrence of tumor regression score=3 tumors suggests an aggressive biology of these tumors. Further studies are needed to characterize tumors that are less likely to respond to radiotherapy and to personalize preoperative treatment decisions.

Article Info

Article Type

Research Article

Publication history

Received: Tue 22, Oct 2019
Accepted: Thu 14, Nov 2019
Published: Tue 26, Nov 2019

Copyright

© 2023 Shmuel Avital. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Hosting by Science Repository.
DOI: 10.31487/j.COR.2019.5.18