Perfusion CT scan may predict response to therapy in pancreatic ductal adenocarcinoma

Perfusion computed tomography (CT) scan may be useful in predicting the histopathologic response to therapy in pancreatic ductal adenocarcinoma, revealed a study published in Radiology.

Pancreatic ductal adenocarcinoma (PDAC) is the most common malignancy of the pancreas. PDAC is an aggressive and difficult malignancy to treat. Complete surgical removal of the tumor remains the only chance for cure, however 80-90% of patients have disease that is surgically incurable at the time of clinical presentation. Despite our advancing knowledge of the tumor biology of PDAC, improvement in diagnosis and management, and the rise of centers specialized in the care of patients with PDAC, the prognosis remains strikingly poor.

In patients with pancreatic ductal adenocarcinoma, higher baseline blood flow determined by using perfusion CT was indicative of the tumor's response to chemotherapy and radiation therapy. Change in tumor size at CT is insufficient for reliable assessment of treatment response after neoadjuvant chemotherapy and radiation therapy (CRT) and shows poor correlation with histologic grading of response.

The study was designed to investigate the use of perfusion CT to predict the response of pancreatic ductal adenocarcinoma (PDA) to CRT.

Between June 2016 and May 2018, study participants with biopsy-proven PDA were prospectively recruited to undergo perfusion CT before and after planned CRT. Blood flow (BF), blood volume (BV), and permeability–surface area product (PSP) were quantified from CT images. Participants were categorized into responders and non-responders according to therapy response. The Mann-Whitney test was used to compare the baseline perfusion values between responders and nonresponders, and the Wilcoxon matched-pairs signed rank test was used to compare perfusion values before and after CRT.

The final cohort of 21 participants underwent dynamic perfusion (dual-source) CT before neoadjuvant CRT. All participants underwent pancreatectomy. Eighteen participants underwent post-CRT perfusion CT. Baseline BF was higher in responders than in nonresponders, while BV and PSP were similar between groups median PSP, Response Evaluation Criteria in Solid Tumors (RECIST) and carbohydrate antigen (CA) 19-9 showed no correlation with perfusion parameters or histopathologic response. For responders, perfusion parameters increased after CRT (eg, median BF, 54. The perfusion change in nonresponders was not significant.

To conclude the study the authors wrote that: " Perfusion CT may be useful in helping predict the histopathologic response to therapy in pancreatic ductal adenocarcinoma."