Michael Chuong, MD, FACRO, discusses patterns of locoregional recurrence following guided radiation therapy in pancreatic cancer.
Michael Chuong, MD, FACRO, medical director, Proton Therapy and Photon Therapy, Department of Radiation Oncology, vice chair, medical director, Radiation Oncology, lead, gastrointestinal radiation service, Baptist Health, discusses patterns of locoregional recurrencefollowing guided radiation therapy in pancreatic cancer.
A study aimed to examine the locations of disease recurrence in patients with pancreatic cancer, particularly whether their disease recurred within or near the tumors that had been treated, Chuong begins. Elective, or prophylactic, treatment, which began in 2019, initially covered a small treatment area, he notes. Chuong states that there were concerns about patients’ ability to tolerate elective treatment because it used high doses. However, as investigators observed that patients tolerated it well, the elective treatment volumes expanded significantly over time, he emphasizes.
These study findings revealed several key points. First, the local recurrence rate was 14.4% (n = 15) out of the 104 patients assessed, which is significantly lower than that typically expected with standard-dose radiation, Chuong expands. Secondly, the recurrence locations differed from those expected with standard radiation, especially when targeting only the visible tumor itself. Instead, disease tended to recur at atypical, more distant locations, particularly as investigators expanded the elective treatment volumes, he says. The analysis indicates that the investigative technique and approach reduced the absolute incidence of recurrences in those areas and likely prevented many recurrences that would normally occur in or around the tumors, Chuong notes. Investigators did not routinely use elective treatment in locoregional areas where tumors didn't return. However, following this study, investigators incorporated these additional areas into routine treatment, Chuong says.
This study represents the first of its kind, examining patterns of locoregional recurrence in patients receiving ablative radiation, Chuong continues. These findings contrast with evaluations in patients receiving non-ablative radiation. Notably, these outcomes, particularly regarding locoregional recurrence rates, are much lower than those expected with standard radiation doses, he adds. These data support the regular use of elective radiation therapy in patients with pancreatic cancer and represent an unconventional but promising approach, he concludes.