TY - JOUR
T1 - Clinical Complete Response in Patients With Rectal Adenocarcinoma Treated With Short-Course Radiation Therapy and Nonoperative Management
AU - Chin, Re I.
AU - Roy, Amit
AU - Pedersen, Katrina
AU - Huang, Yi
AU - Hunt, Steven
AU - Glasgow, Sean C.
AU - Tan, Benjamin
AU - Wise, Paul E.
AU - Silviera, Matthew L.
AU - Smith, Radhika
AU - Suresh, Rama
AU - Badiyan, Shahed N.
AU - Shetty, Anup
AU - Henke, Lauren E.
AU - Mutch, Matthew G.
AU - Kim, Hyun
N1 - Publisher Copyright:
© 2021 Elsevier Inc.
PY - 2022/3/1
Y1 - 2022/3/1
N2 - Purpose: This study aimed to determine the clinical efficacy and safety of nonoperative management (NOM) for patients with rectal cancer with a clinical complete response (cCR) after short-course radiation therapy and consolidation chemotherapy. Methods and Materials: Patients with stage I-III rectal adenocarcinoma underwent short-course radiation therapy followed by consolidation chemotherapy between January 2018 and May 2019 (n = 90). Clinical response was assessed by digital rectal examination, pelvic magnetic resonance imaging, and endoscopy. Of the patients with an evaluable initial response, those with a cCR (n = 43) underwent NOM, and those with a non-cCR (n = 43) underwent surgery. The clinical endpoints included local regrowth-free survival, regional control, distant metastasis-free survival, disease-free survival, and overall survival. Results: Compared with patients with an initial cCR, patients with initial non-cCR had more advanced T and N stage (P = .05), larger primary tumors (P = .002), and more circumferential resection margin involvement on diagnostic magnetic resonance imaging (P < .001). With a median follow-up of 30.1 months, the persistent cCR rate was 79% (30 of 38 patients) in the NOM cohort. The 2-year local regrowth-free survival was 81% (95% confidence interval [CI], 70%-94%) in the initial cCR group, and all patients with local regrowth were successfully salvaged. Compared with those with a non-cCR, patients with a cCR had improved 2-year regional control (98% [95% CI, 93%-100%] vs 85% [95% CI, 74%-97%], P = .02), distant metastasis-free survival (100% [95% CI, 100%-100%] vs 80% [95% CI, 69%-94%], P < .01), disease-free survival (98% [95% CI, 93%-100%] vs 71% [95% CI, 59%-87%], P < .01), and overall survival (100% [95% CI, 100%-100%] vs 88% [95% CI, 79%-98%], P = .02). No late grade 3+ gastrointestinal or genitourinary toxicities were observed in the patients who underwent continued NOM. Conclusions: Short-course radiation therapy followed by consolidation chemotherapy may be a feasible organ preservation strategy in rectal cancer. Additional prospective studies are necessary to evaluate the safety and efficacy of this approach.
AB - Purpose: This study aimed to determine the clinical efficacy and safety of nonoperative management (NOM) for patients with rectal cancer with a clinical complete response (cCR) after short-course radiation therapy and consolidation chemotherapy. Methods and Materials: Patients with stage I-III rectal adenocarcinoma underwent short-course radiation therapy followed by consolidation chemotherapy between January 2018 and May 2019 (n = 90). Clinical response was assessed by digital rectal examination, pelvic magnetic resonance imaging, and endoscopy. Of the patients with an evaluable initial response, those with a cCR (n = 43) underwent NOM, and those with a non-cCR (n = 43) underwent surgery. The clinical endpoints included local regrowth-free survival, regional control, distant metastasis-free survival, disease-free survival, and overall survival. Results: Compared with patients with an initial cCR, patients with initial non-cCR had more advanced T and N stage (P = .05), larger primary tumors (P = .002), and more circumferential resection margin involvement on diagnostic magnetic resonance imaging (P < .001). With a median follow-up of 30.1 months, the persistent cCR rate was 79% (30 of 38 patients) in the NOM cohort. The 2-year local regrowth-free survival was 81% (95% confidence interval [CI], 70%-94%) in the initial cCR group, and all patients with local regrowth were successfully salvaged. Compared with those with a non-cCR, patients with a cCR had improved 2-year regional control (98% [95% CI, 93%-100%] vs 85% [95% CI, 74%-97%], P = .02), distant metastasis-free survival (100% [95% CI, 100%-100%] vs 80% [95% CI, 69%-94%], P < .01), disease-free survival (98% [95% CI, 93%-100%] vs 71% [95% CI, 59%-87%], P < .01), and overall survival (100% [95% CI, 100%-100%] vs 88% [95% CI, 79%-98%], P = .02). No late grade 3+ gastrointestinal or genitourinary toxicities were observed in the patients who underwent continued NOM. Conclusions: Short-course radiation therapy followed by consolidation chemotherapy may be a feasible organ preservation strategy in rectal cancer. Additional prospective studies are necessary to evaluate the safety and efficacy of this approach.
UR - http://www.scopus.com/inward/record.url?scp=85119414709&partnerID=8YFLogxK
U2 - 10.1016/j.ijrobp.2021.10.004
DO - 10.1016/j.ijrobp.2021.10.004
M3 - Article
C2 - 34653579
AN - SCOPUS:85119414709
SN - 0360-3016
VL - 112
SP - 715
EP - 725
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
IS - 3
ER -