講演情報
[ASCRS]Response to Neoadjuvant Therapy Predicts Metastatic Burden and Survival After Distant Metastasis in Locally Advanced Rectal Cancer
Despoina Kanata, MD1, Sabrina Lin, MS2, Francesca Roufael, MD1, Christina Lee, MD1, Emmanouil Pappou, MD, PhD1, Georgios Karagkounis, MD1, Li-Xuan Qin, PhD2, Julio Garcia-Aguilar, MD, PhD1 (1. Department of Colorectal Surgery, Memorial Sloan Kettering Cancer Center, United States of America, 2. Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, United States of America)
Background: Tumor response to neoadjuvant therapy is associated with the risk of distant metastasis and long-term survival in patients with locally advanced rectal cancer. These differences are thought to reflect intrinsic tumor biology. However, it remains unclear whether tumor response is also associated with survival after the development of distant metastasis.
Objective: To investigate overall survival after metastasis according to the grade of response of the primary tumor.
Design: Retrospective cohort study.
Settings: Single tertiary cancer center.
Patients: Patients with primary locally advanced rectal cancer treated with neoadjuvant therapy between 2007 and 2023 who developed distant metastasis after post-treatment restaging.
Main Outcomes Measures: Overall survival from a two-year landmark after restaging and from the date of distant metastasis.
Results: The study cohort included 389 patients (280 with incomplete response, 57 with tumor regrowth, and 52 with complete response). Metastatic burden differed significantly between groups, with oligometastatic disease observed in 65% of patients with complete response and 68% of patients with tumor regrowth, compared to 47% of patients with incomplete response (p=0.002). Median overall survival was 5.9 years in the complete response group, 4.1 years in the incomplete response group, and 3.7 years in the tumor regrowth group, with no statistically significant difference (p=0.2). Older age, high tumor grade and local recurrence development were associated with worse overall survival.
Limitations: This was a single-center retrospective study.
Conclusions: In patients with locally advanced rectal cancer who develop distant metastasis after neoadjuvant therapy, metastatic burden differs according to tumor response, but overall survival is not significantly different between response groups. Survival is primarily associated with age, tumor grade, and the development of local recurrence in addition to distant metastasis.
Objective: To investigate overall survival after metastasis according to the grade of response of the primary tumor.
Design: Retrospective cohort study.
Settings: Single tertiary cancer center.
Patients: Patients with primary locally advanced rectal cancer treated with neoadjuvant therapy between 2007 and 2023 who developed distant metastasis after post-treatment restaging.
Main Outcomes Measures: Overall survival from a two-year landmark after restaging and from the date of distant metastasis.
Results: The study cohort included 389 patients (280 with incomplete response, 57 with tumor regrowth, and 52 with complete response). Metastatic burden differed significantly between groups, with oligometastatic disease observed in 65% of patients with complete response and 68% of patients with tumor regrowth, compared to 47% of patients with incomplete response (p=0.002). Median overall survival was 5.9 years in the complete response group, 4.1 years in the incomplete response group, and 3.7 years in the tumor regrowth group, with no statistically significant difference (p=0.2). Older age, high tumor grade and local recurrence development were associated with worse overall survival.
Limitations: This was a single-center retrospective study.
Conclusions: In patients with locally advanced rectal cancer who develop distant metastasis after neoadjuvant therapy, metastatic burden differs according to tumor response, but overall survival is not significantly different between response groups. Survival is primarily associated with age, tumor grade, and the development of local recurrence in addition to distant metastasis.