A case of pseudomyxoma peritonei arising from a perforated intraductal papillary mucinous neoplasm that underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Pseudomyxoma peritonei (PMP) of pancreatic origin arising from an intraductal papillary mucinous neoplasm (IPMN) is rare. Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has been established as the optimal treatment for PMP. However, the benefits and safety of CRS with HIPEC for treating PMP of pancreatic origin remain unclear. Herein, we describe a case of PMP of pancreatic origin that was treated with CRS and HIPEC without postoperative complications. A 75-year-old woman was referred to our department. Computed tomography (CT) revealed a multilocular cystic tumor in the pancreatic tail, notable mucinous ascites in the abdominal cavity, and scalloping of the liver and spleen. CT did not reveal the appendix, and the ovaries were normal in size. The patient was diagnosed with PMP of pancreatic origin, and CRS and HIPEC were performed. Intraoperatively, the pancreatic tumor was perforated, and there was a large amount of mucinous ascites. We performed distal pancreatectomy in addition to CRS and HIPEC, with no intraoperative complications. The postoperative course was uneventful, and the patient survived after 6 months without recurrence. CRS with HIPEC may be a feasible treatment option for PMP of pancreatic origin.

Pseudomyxoma peritonei: visceral scalloping on CT is a predictor of recurrence after complete cytoreductive surgery.

OBJECTIVES: Pseudomyxoma peritonei (PMP) is characterized by peritoneal dissemination of gelatinous ascites following rupture of a mucinous tumor. Treatment by cytoreductive surgery (CRS) has improved its prognosis. Although visceral scalloping, notably liver scalloping, on computed tomography (CT) is a typical feature of PMP, its prognostic value remains unknown. We aimed to investigate the efficacy of liver scalloping in predicting recurrence in PMP patients. METHODS: Among 159 consecutive patients with PMP who had contrast-enhanced CT between September 2012 and December 2018, 64 treatment-naïve patients who subsequently underwent CRS with complete resection (i.e., completeness of cytoreduction score (CC)-0 or CC-1), were included in analysis. Presence of liver scalloping and maximum thickness of mucin deposition at the liver surface were evaluated on CT. Disease-free survival (DFS) was determined based on the combination of postoperative CT features and tumor marker values. RESULTS: Median follow-up was 24.3 months. CT revealed liver scalloping in 40/64 (63.4%) patients. Kaplan-Meier analysis showed significantly shorter DFS in patients with scalloping than in those without (p = 0.001; hazard ratio, 4.3). In patients with scalloping, greater mucin deposition (thickness ≥ 20 mm) significantly correlated with poorer DFS (p = 0.042). In multivariate Cox proportional hazards regression including CC status, pathologic type, and tumor markers, the presence of scalloping independently and significantly correlated with DFS (p = 0.031). CONCLUSIONS: Liver scalloping was an independent predictor even after adjusting for clinical covariates. The presence of liver scalloping can lead to a high recurrence rate after CRS. KEY POINTS: • The presence of liver scalloping is a prognostic factor independent of histological grade and tumor markers. • Greater mucin deposition (thickness ≥ 20 mm at the liver surface) is associated with higher recurrence rates in patients with liver scalloping.

Hepatectomy for metachronous colorectal liver metastases following complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal metastases: a report of three cases.

BACKGROUND: Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal metastasis (PM) from colorectal cancer (CRC) has been reported to substantially improve the prognosis and the quality of life of patients in comparison to systemic chemotherapy or palliative approaches. This study aimed to demonstrate the safety and feasibility of hepatectomy for metachronous liver metastases from CRC following CRS and HIPEC for PM on the basis of three case reports. CASE PRESENTATION: We describe three cases involving patients who underwent hepatectomy for metachronous liver metastases from CRC after CRS and HIPEC for PM. All patients underwent CRS and HIPEC after primary tumor resection, and hepatectomy was performed for the metachronous liver metastases after CRS and HIPEC. The hepatectomy procedures for cases 1, 2, and 3 were left hemihepatectomy and partial resection of S5, posterior sectionectomy, and left-lateral sectionectomy and partial resection of S5 and S8, respectively. Although adhesion of surrounding organs to the liver surface was observed on a broad level, dissections and hepatectomy could be performed safely. No recurrence was detected in cases 1 and 2 after hepatectomy. In case 3, liver metastases were detected from the time of the initial diagnosis of the primary tumor, and complete remission was achieved once with systemic chemotherapy. Although we performed hepatectomy for the recurrence of liver metastases after complete remission, early re-recurrence was observed after hepatectomy. CONCLUSIONS: Hepatectomy for metachronous liver metastases after CRS and HIPEC for PM could be a multi-modality treatment option for CRC recurrence.