Consistent Response on Challenge and Rechallenge of Liposomal Irinotecan in a Patient with Metastatic Pancreatic Adenocarcinoma Previously Treated with Gemcitabine plus Nab-Paclitaxel: A Case Report

Approximately 80% of pancreatic cancer is diagnosed at an advanced stage, due to lack of or vague symptoms when the cancer is still localized, leading to a high mortality rate. Known risk factors for developing pancreatic cancer are family history, obesity, type 2 diabetes, and alcohol and tobacco use. There has been a remarkable development in diagnosis modalities and molecular testing, but early detection is still infrequent. The majority of clinical trials have not shown significant efficacy in pancreatic cancer, and treatment strategy remains limited. Additional prognostic factors should be highlighted to obtain appropriate treatment options, including precision medicine, and improve survival outcomes. After the PRODIGE study in 2011 and the MPAC trial in 2013, a new drug (liposomal irinotecan; Onivyde ®) appeared in the strategy, especially after failure of gemcitabine-based treatment. In 2016, the NAPOLI-1 trial showed evidence of the efficacy of the liposomal irinotecan combination (liposomal irinotecan +5-fluorouracile + folinic acid); now, it is considered the standard treatment for relapsing patients. Since NAPOLI-1, real-world data have provided similar results. Herein, we report the story of a 61-year-old woman who was treated with liposomal irinotecan combination (nal-IRI/5-FU/LV) for 8 months with good surgical response, but treatment was discontinued due to economic burden. After the start of treatment (or 1? cycle of liposomal irinotecan treatment), the patient was in a better condition. The liver metastases had disappeared. The combination with liposomal irinotecan was re-administered with patient's approval. Upon rechallenge with the liposomal irinotecan combination, she showed a partial response, and the treatment was given for 7 months. In this report, we tried to identify the prognostic factors leading to the efficacy of the liposomal irinotecan combination.