Mismatch-repair-deficient metastatic pancreatic ductal adenocarcinoma with a germline PALB2 mutation: unusual genetics, unusual clinical course

<span class="paragraphSection">A previously healthy 54-year old man was diagnosed with metastatic pancreatic ductal adenocarcinoma (PDAC) in February 2015; the primary tumor was localized in the tail of the pancreas. Histological confirmation of disease was based on a liver biopsy that showed a poorly differentiated adenocarcinoma. The patient had no family history of PDAC; however, two of his paternal aunts died of breast cancer. The patient started chemotherapy with a FOLFIRINOX regimen in March 2015 [<a href="#mdw564-B1" class="reflinks">1</a>], that was de-escalated to mFOLFOX-6 and finally 5-FU/FA due to toxicity (thrombocytopenia, peripheral neuropathy); maintenance 5-FU/FA was given until June 2016. During this treatment, a very good partial response occurred, with a decline in CA 19-9 levels from 8.149 U/ml (pre-treatment) to a nadir of 5 U/ml in March 2016. On sequential CT imaging studies, the liver metastases as well as the pancreatic primary decreased dramatically in size, and the radiographic finding correlated well with a rapid clinical benefit response (e.g. no further need for analgesics since May 2015).</span>
Source: Annals of Oncology - Category: Cancer & Oncology Source Type: research