Identifying Prognostic Factors in Japanese Women with Pseudomyxoma Peritonei: A Retrospective Clinico-Pathological Study of the Tohoku Gynecologic Cancer Unit

Abstract

Pseudomyxoma peritonei (PMP) is a rare condition of mucinous ascites associated mainly with mucinous tumors of appendix or ovary. PMP often recurs after treatment and may eventually cause death by abdominal visceral dysfunction via compression with mucinous ascites. Although radical peritonectomy and hyperthermic intra-peritoneal chemotherapy are becoming popular globally, the optimal treatment of PMP has not been established in Japan. We conducted a retrospective multicenter study to clarify the optimal treatment and the prognostic factors of PMP. A total of 23 patients with PMP were analyzed in the Tohoku Gynecologic Cancer Unit (TGCU). Clinical and follow-up data were retrieved and a central pathology review was performed. The median follow-up period was 46 months. Eleven patients underwent complete resection. There were 7 deaths out of 13 recurrences/progressions in this period. All the recurrence/ progression was confined to the abdomen. Unexpectedly, neither radical peritonectomy nor hyperthermic intra-peritoneal chemotherapy had been performed, indicating that both radical peritonectomy and hyperthermic intra-peritoneal chemotherapy are not yet popular in Japan. The medians of overall survival and disease-free period were 166 months and 30 months, respectively. Univariate and multivariate analyses revealed that the only prognostic factor was macroscopic residual tumor (P = 0.022). Although chemotherapy was not a prognostic factor (P = 0.16), those who received intra-peritoneal chemotherapy tended to have a better prognosis than those who received systemic or no chemotherapy (P = 0.064). In conclusion, the macroscopic residual tumor is an important prognostic factor in Japanese patients with PMP.

The Prognostic Impact of Pathology on Patients With Pseudomyxoma Peritonei Undergoing Debulking Surgery: A Systematic Review and Meta-Analysis of Retrospective Studies

“…In addition to pathological type and surgical treatment, there are many factors related to the prognosis of PMP patients; for example, the extent of peritoneal seeding [which can be quantified by the Peritoneal Cancer Index (PCI)] and the use of chemotherapy, such as locoregional chemotherapy, including intraperitoneal chemotherapy (IPC) and HIPEC (33), has been studied and reported in many countries and regions around the world (34)(35)(36) and can improve the 5-year survival rates, although with higher mortality and morbidity (37,38). If there is no visible residual cancer or residual tumor deposits that measure <2.5 mm in size (CRR0 or CRR1) after surgery, chemotherapeutic drugs can penetrate into the cells and eradicate residual lesions (39,40).…”

Pseudomyxoma peritonei: a clinical case of this poorly understood condition

“…An interesting fact is that chemotherapy may improve survival only if administered intraperitoneally,13,19 as reported by the Mayo Clinic, Gough DB 13. Systemic chemotherapy seems not to affect prognosis 19…”

“…Unfortunately, the majority of patients develop recurrence after treatment,19 which requires repeated surgical intervention 6. Elevated tumor markers such as carcinoembryonic antigen level, cancer antigen 19-9 level, and cancer antigen 125 level indicate advanced disease and may rise in association with recurrent disease 12,20…”

Pseudomyxoma peritonei: The struggle of a lifetime and the hope of a cure - a rare diagnosis with review of the literature

“…The introduction of HIPEC as a treatment modality in the field of surgical oncology has revolutionized the treatment protocols for various malignancies, including PMP. Consequently, HIPEC has become a new treatment option for PMP [ 2 , 9 , 14 , 17 , 22 ]. Sugarbaker and Chang [ 4 ] conducted a study with 385 patients diagnosed with appendiceal malignancies that had spread to the peritoneal surfaces.…”