Lymphopenia—a condition where lymphocyte levels in blood are below normal—is frequently caused by chemoradiation (CRT). Since lymphopenia is associated with worse survival outcomes in patients with cancer, there is a huge need to decrease this condition. Researchers found that in patients with nonmetastatic, unresectable pancreatic ductal adenocarcinoma (PDAC) who have been treated with neoadjuvant 5-fluorouracil (5FU)/leucovorin/irinotecan/oxaliplatin (FOLFIRINOX) and CRT, severe lymphopenia can potentially be prevented by lowering the radiotherapy dose.
For this study, which will be presented this coming weekend at the Gastrointestinal Cancers Symposium, 138 patients met the inclusion criteria: biopsy-proven diagnosis of unresectable PDAC, absence of distant metastasis, receipt of neoadjuvant FOLFIRINOX followed by CRT, and absolute lymphocyte count (ALC) available before and two months after starting CRT. The typical CRT treatment used consisted of 5FU or capecitabine and radiotherapy (RT) (58.8 Gy over 28 fractions).
After a median follow-up of 16 months, the researchers found that patients with severe lymphopenia had received higher doses of RT with a longer duration of treatment compared with patients who did not have severe lymphopenia. In addition, severe lymphopenia at two months after CRT initiation was linked with increased hazards of death. Overall survival at 12 months was found to be 73% versus 90% for those with versus those without severe lymphopenia, respectively. Patients who received a greater number of neoadjuvant FOLFIRINOX cycles before CRT were found to have a lower hazard of death.
"Closer observation in high-risk patients and minimization of RT dose and duration are potential approaches to mitigating CRT-related lymphopenia," conclude the study authors, led by Daniel W. Kim, MD, MBA, a clinical fellow in radiation oncology at Massachusetts General Hospital. "Our findings also suggest an important role of the host immunity in pancreatic cancer outcomes, supporting the ongoing efforts of immunotherapy trials in pancreatic cancer."
For More Information
Kim DW, Lee G, Weekes CD, et al (2021). Prognostic impact of chemoradiation-related lymphopenia in patients with locally advanced pancreatic cancer. J Clin Oncol (Gastrointestinal Cancers Symposium Abstracts), 39(suppl_3). Abstract 439.
Image courtesy of Ed Uthman. Licensed under CC BY 2.0