CT imaging findings following treatment with combination SBRT and chemotherapy versus stand-alone chemotherapy for locally advanced pancreatic adenocarcinoma
摘要
To evaluate imaging findings of patients with locally advanced pancreatic cancer (LAPC) following treatment with combination stereotactic body radiotherapy (SBRT) and chemotherapy versus stand-alone chemotherapy.
MethodsThis retrospective study included patients with LAPC who received combination SBRT/chemotherapy versus those that received stand-alone chemotherapy from 2005 to 2018. Comparisons were made pre-treatment and at four standardized post-treatment intervals (1 month, 3–6 months, 7–12 months, greater than 12 months) in patients without disease progression. Imaging variables included degree of vascular involvement graded on a standardized scale and peripancreatic fat stranding. A p-value < 0.05 was considered significant.
ResultsA total of 96 patients were included, 64 patients (37 men; mean age, 68 ± 11 years) treated with SBRT/chemotherapy and 32 patients (17 men; mean age, 69 ± 10 years) treated with stand-alone chemotherapy. Increased vascular involvement over time in the absence of disease progression was significantly higher in the SBRT/chemotherapy group (17%) versus the stand-alone chemotherapy group (9%), p = 0.004 (95% CI 2–12%). Peripancreatic fat stranding increased over time in the SBRT/chemotherapy group being present in 29/64 (45%) patients on the pre-treatment computed tomography (CT) versus 55/64 (86%) patients on the last recorded CT, p < 0.001 (McNemar OR = 14, 95% CI 3.3–58.8). No significant change in peripancreatic fat stranding over time was noted in the stand-alone chemotherapy group being present in 9/32 (28%) patients on the pre-treatment CT and 7/32 (22%) patients on the last imaging recorded, p = 0.45 (McNemar OR = 2, 95% CI 0.4–10.9).
ConclusionsIncreased vascular involvement and peripancreatic fat stranding over time in LAPC patients treated with combination SBRT/chemotherapy should be a potential anticipated treatment-related effect, not necessarily indicating disease progression.