Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in New Zealand: peri-operative outcomes and service development over a decade.

BACKGROUND: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is the standard of care for selected cases of peritoneal surface malignancy. However, due to its morbidity and learning curve, it is only delivered in six centres in Australia and Aotearoa New Zealand (AoNZ). In this study, we report peri-operative morbidity and mortality following CRS/HIPEC at Waikato and Braemar Hospitals, which have treated patients from all regions of AoNZ since 2008. METHODS: We retrospectively reviewed a database of all patients undergoing CRS and HIPEC from 01/01/2008 to 01/11/2020 at Waikato and Braemar Hospitals. RESULTS: Two-hundred and forty procedures were performed for 221 patients with a mean age of 55, including 22 (9.2%) re-do procedures. One hundred and eighty-six cases were European, 32 were Maori, and 16 were Pasifika. There were 152 pseudomyxoma peritonei, 39 colorectal adenocarcinomas, 29 appendiceal cancers, 8 ovarian cancers, 6 peritoneal mesothelioma, and 6 other tumour types. The median PCI was 16. HIPEC was administered to 196 out of 196 CC0/1 cases (100%) and 3 out of 44 CC2/3 cases (6.8%). Fifty-six cases (23.3%) had at least one major complication. There were two mortalities (0.8%) within 30 days. The median length of stay was 11 days. Operative duration was identified as an independent risk factor for major complications. There was considerable variation in the number of referrals from different regions of AoNZ. Over time, a decline in major complication rate is seen with increased case volume. CONCLUSION: The Waikato region has achieved favourable short-term outcomes following CRS/HIPEC.

Long-term survival following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in Waikato, Aotearoa New Zealand: a 12-year experience.

BACKGROUNDS: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have improved survival for selected cases of peritoneal surface malignancy. In 2008, a CRS/HIPEC service was first established in Aotearoa New Zealand (AoNZ) at Waikato and Braemar Hospitals in the Waikato region. METHODS: This is a retrospective review of a prospectively maintained database of all patients undergoing CRS/HIPEC from 1 January 2008 to 1 November 2020 at Waikato and Braemar Hospitals. We analysed long-term survival and predictors of survival for each tumour type. RESULTS: 240 procedures were performed for 221 patients, including 22 re-do procedures. Cases had a median peritoneal cancer index of 16. Complete cytoreduction (CC0-1) was achieved in 196 cases (81.7%). All complete cytoreduction cases received HIPEC. There were 152 pseudomyxoma peritonei (PMP), 39 colorectal cancers (CRC), 29 appendiceal cancers, eight ovarian cancers, six peritoneal mesotheliomas, and six other cancers. The 5-year overall survival (OS) for PMP with acellular mucin, low-grade mucinous carcinoma peritonei, and high-grade mucinous carcinoma peritonei with or without signet cells were 91.6%, 80.5%, and 72.2%, respectively. 2- and 5-year OS in CRC were 56.7% and 40.4%. The achievement of complete cytoreduction improved the 5-year OS to 87.9% across all PMP and 45.1% in colorectal cancer. Incomplete cytoreduction predicted worse survival in appendiceal PMP. In colorectal cancer, worse survival was predicted in those who had incomplete cytoreduction, liver metastasis, and presentation with obstruction and perforation. CONCLUSION: Favourable long-term outcomes following CRS/HIPEC for peritoneal surface malignancy have been achieved in AoNZ through the Waikato peritonectomy service.