Optimal treatment strategy for patients with pancreatic cancer having positive peritoneal cytology: A nationwide multicenter retrospective cohort study supervised by the Japanese Society of Hepato-Biliary-Pancreatic Surgery

Kyohei Ariake; Masamichi Mizuma; Michiaki Unno; Sohei Satoi; Naoto Yamamoto; Masamichi Hayashi; Manabu Kawai; Hirofumi Akita; Eiji Toyoda; Tsutomu Fujii; Masaru Sasaki; Kenichi Hakamada; Jota Watanabe; Etsuro Hatano; Masaaki Hidaka; Satoshi Hirano; Hiroshi Kurahara; Ippei Matsumoto; Goro Honda; Toshiro Ogura; Masafumi Nakamura; Itaru Endo

doi:10.1002/jhbp.12074

Optimal treatment strategy for patients with pancreatic cancer having positive peritoneal cytology: A nationwide multicenter retrospective cohort study supervised by the Japanese Society of Hepato-Biliary-Pancreatic Surgery

J Hepatobiliary Pancreat Sci. 2024 Sep 24. doi: 10.1002/jhbp.12074. Online ahead of print.

Authors

Kyohei Ariake^{1

2}, Masamichi Mizuma¹, Michiaki Unno¹, Sohei Satoi³, Naoto Yamamoto⁴, Masamichi Hayashi⁵, Manabu Kawai⁶, Hirofumi Akita⁷, Eiji Toyoda⁸, Tsutomu Fujii⁹, Masaru Sasaki¹⁰, Kenichi Hakamada¹¹, Jota Watanabe¹², Etsuro Hatano¹³, Masaaki Hidaka¹⁴, Satoshi Hirano¹⁵, Hiroshi Kurahara¹⁶, Ippei Matsumoto¹⁷, Goro Honda¹⁸, Toshiro Ogura¹⁹, Masafumi Nakamura^{20

21}, Itaru Endo^{21

22}

Affiliations

¹ Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
² Department of Gastroenterological Surgery, Sendai City Medical Center Sendai Open Hospital, Sendai, Japan.
³ Department of Surgery, Kansai Medical University, Hirakata, Japan.
⁴ Department of Gastrointestinal Surgery, Kanagawa Cancer Center, Yokohama, Japan.
⁵ Department of Surgery, Graduate School of Medicine, Nagoya University, Nagoya, Japan.
⁶ Second Department of Surgery, Wakayama Medical University School of Medicine, Wakayama, Japan.
⁷ Department of Gastroenterological Surgery, Osaka International Cancer Institute, Osaka, Japan.
⁸ Department of Surgery, Otsu Red Cross Hospital, Otsu, Japan.
⁹ Department of Surgery and Science, Faculty of Medicine, Academic Assembly, University of Toyama, Toyama, Japan.
¹⁰ Department of Surgery, JA Hiroshima General Hospital, Hatsukaichi, Japan.
¹¹ Department of Gastroenterological Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
¹² Department of Gastrointestinal Surgery, Ehime Prefectural Central Hospital, Matsuyama, Japan.
¹³ Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
¹⁴ Department of Digestive and General Surgery, Shimane University Faculty of Medicine, Izumo, Japan.
¹⁵ Department of Gastroenterological Surgery II, Hokkaido University Faculty of Medicine, Sapporo, Japan.
¹⁶ Department of Digestive Surgery, Kagoshima University, Kagoshima, Japan.
¹⁷ Department of Surgery, Faculty of Medicine, Kindai University, Osakasayama, Japan.
¹⁸ Department of Surgery, Institute of Gastroenterology, Tokyo Women's Medical University, Tokyo, Japan.
¹⁹ Department of Gastroenterological Surgery, Saitama Cancer Center, Saitama, Japan.
²⁰ Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
²¹ Japanese Society of Hepato-Biliary-Pancreatic Surgery, Tokyo, Japan.
²² Department of Gastroenterological Surgery, Graduate School of Medicine, Yokohama City University, Yokohama, Japan.

PMID: 39317950
DOI: 10.1002/jhbp.12074

Abstract

Background: The aim of this study was to determine the optimal treatment for patients with pancreatic cancer (PaCa) having positive peritoneal cytology (PPC).

Methods: This multicenter retrospective study included patients with PPC treated at 78 high-volume centers between January 2012 and December 2020. Prognoses after resection (S-group) and initiation of nonsurgical treatment (N-group) were compared. Prognostic factors for survival in both groups were analyzed. Detailed characteristics of conversion surgery (CS) in the N-group were evaluated.

Results: In total, 568 enrolled patients were classified into an S-group (n = 445) or an N-group (n = 123). Median survival times (MSTs) were 19.0 months and 19.3 months, respectively, with no significant difference in prognosis (p = .845). The intervenable prognostic factors for survival were adjuvant treatment in the S-group (p < .001) and CS in the N-group (p < .001). Following CS, the MST was prolonged to 45.6 months, and peritoneal or liver recurrence decreased considerably. CS can be expected if PPC is diagnosed before neoadjuvant treatment and when combination treatment is initiated.

Conclusion: Surgical resection may not be beneficial for improving survival when PPC is evident. Chemotherapy aiming for CS may be the optimal treatment for such patients.

Keywords: chemotherapy; conversion surgery; pancreatic cancer; peritoneal cytology.

Grants and funding

Japanese Society of Hepato-Biliary-Pancreatic Surgery