Comparative outcomes of treatment modalities in nonagenarians with nonmetastatic pancreatic adenocarcinoma

Background: There has been an increase in the elderly patient population seeking care for pancreatic ductal adenocarcinoma (PDAC). This study aimed to delineate the effectiveness of therapeutic options in nonagenarians (aged 90-99 years) diagnosed with resectable PDAC. Methods: This study used the National Cancer Database to identify patients with nonmetastatic PDAC (stage I-III) from 2004 to 2021. The study compared median overall survival (mOS) using Kaplan-Meier curves among 5 treatment categories: surgery, surgery along with chemoradiation, chemotherapy alone, radiotherapy alone, and chemoradiation alone. Cox proportional hazards regression was used in multivariate analyses. Results: Of 459,174 patients, 793 aged >= 90 years had nonmetastatic PDAC. Of 793 patients, 245 (30.9 %) underwent chemotherapy alone, 296 (37.3 %) underwent radiotherapy alone, 162 (20.4 %) underwent chemoradiation alone, 58 (7.3 %) underwent curative-intent resection, and 32 (4.0 %) underwent surgery combined with chemoradiation. The mOS estimates in different treatment modalities were 9.5 months (95 % CI, 6.7-14.5) for surgery alone, 19.1 months (95 % CI, 2.4-64.3) for surgery combined with chemoradiation, 8.2 months (95 % CI, 7.2-9.2) for chemotherapy alone, 8.4 months (95 % CI, 7.6-9.6) for radiotherapy alone, and 11.2 months (95 % CI, 8.7-12.9) for chemoradiation alone (P < .001). In multivariate analysis, the odds of survival were better for patients who underwent surgery alone than for those who underwent chemotherapy alone, although the odds of survival did not significantly differ between patients who underwent radiotherapy alone and those who underwent chemoradiation alone. Nonetheless, surgery combined with chemoradiation was associated with decreased mortality risk compared with surgery alone (hazard ratio, 0.46; 95 % CI, 0.25-0.87; P = .02). Operative 30-day mortality rate was 8.8 %, and 90-day mortality rate was 17.8 %. Conclusion: Surgery combined with chemoradiation improved the survival of nonagenarians with PDAC compared with other therapies. However, only 1 in 25 patients received all 3 treatment components. Moreover, our study highlights a very high operative mortality rate in nonagenarians.