Multidisciplinary team approach of treatment of a metastatic gastric carcinoma during pregnancy: a case report.

Background: A 39-year-old woman, G2P0M0, 26 weeks and 4 days pregnant, presented at the hospital with nausea, abnormal increase in abdominal size, respiratory failure due to pleural effusion and ascites, pain and weight loss. She was diagnosed with metastatic gastric carcinoma [signet ring cell carcinoma, human epidermal growth factor receptor 2 (HER2)-negative, programmed death-ligand 1 (PD-L1) combined positive score (CPS) 8, proficient mismatch repair (pMMR)]. Oxygen therapy through a high-flow nasal cannula was started at the intensive care unit and drainage of ascites and pleural effusion was performed. A multidisciplinary team (MDT) was convened to discuss if gastric cancer treatment could safely be started after clinical improvement and, if so, what the consequences could be for the mother and the unborn child. Case Description: An MDT consisting of intensivists, oncologists, clinical pharmacists, gynecologists and nurses was assembled to collaboratively decide, together with the patient and her partner, on the best treatment strategy. A health and safety risk matrix based on literature and experience in practice was used to weigh the risks associated with cancer treatment. Once the patient was stabilized, it was decided to initiate 5-fluorouracil (5-FU), folinic acid and oxaliplatin (FOLFOX) chemotherapy based on the health and safety matrix. Nivolumab was considered to pose too high risks for the unborn and was therefore excluded. The gynecologist closely monitored the unborn child. 5-FU levels were monitored to assess 5-FU kinetics during pregnancy. A normal therapeutic AUC of 25.3 mg·L/h (ref 20-30 mg·L/h) after 46 hours treatment with 4,000 mg 5-FU was found. The patient tolerated the chemotherapy well and showed a good clinical and radiological response. After the first course of chemotherapy, the ascites and pleural drains were removed. In week 33 of the pregnancy, a cesarean section was performed to achieve an optimal balance between risks of chemotherapy and premature birth. A healthy boy was delivered. Post-partum treatment was continued with FOLFOX-nivolumab. Conclusions: This case report demonstrates that, with a multidisciplinary approach and careful monitoring, metastatic gastric cancer can be successfully managed during pregnancy. The good response to FOLFOX therapy and the safe delivery of the child underscore the significance of tailored treatment plans in such complex cases.