Mytomicin-C, Metronomic Capecitabine, and Bevacizumab in Patients With Unresectable or Relapsed Pseudomyxoma Peritonei of Appendiceal Origin

• Published in: Clinical colorectal cancer 2023-12, Vol.22 (4), p.450-456.e1
• Main Authors: Ghelardi, Filippo, Raimondi, Alessandra, Morano, Federica, Randon, Giovanni, Pannone, Alessandra, Guaglio, Marcello, Mazzoli, Giacomo, Nasca, Vincenzo, Milione, Massimo, Leoncini, Giuseppe, Sabella, Giovanna, Greco, Gabriella Francesca, Lampis, Bianca Rosa, Galassi, Margherita, Delfanti, Sara, Nannini, Margherita, Intini, Rossana, Baratti, Dario, Di Bartolomeo, Maria, Deraco, Marcello, Pietrantonio, Filippo
• Format: Article
• Language: English
• Subjects: Appendiceal Neoplasms - pathology; Bevacizumab; Bevacizumab - adverse effects; Capecitabine; Capecitabine - adverse effects; Disease Progression; Humans; Hyperthermia, Induced - methods; Metronomic chemotherapy; Mitomycin - therapeutic use; Mitomycin C; Peritoneal Neoplasms - drug therapy; Prospective Studies; Pseudomyxoma peritonei; Pseudomyxoma Peritonei - drug therapy; Pseudomyxoma Peritonei - pathology
• ISSN: 1533-0028; 1938-0674
• DOI: 10.1016/j.clcc.2023.08.005

Pseudomyxoma peritonei (PMP) is a rare, slow growing tumor, traditionally considered chemoresistant. The only curative approach is cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC). At disease relapse, or in patients with inoperable disease at diagnosis, no standard treatment has been defined, though nonrandomized series showed promising results with fluoropyrimidine-based regimens. We conducted a prospective study in patients with relapsed or unresectable PMP and confirmed disease progression at baseline. Patients received MMC (7 mg/m2 every 6 weeks, up to a maximum of 4 cycles) plus metronomic capecitabine (625 mg/sqm/day b.i.d.) and bevacizumab (7.5 mg/kg every 3 weeks) until disease progression, unacceptable toxicity, or consent withdrawal. Primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS), overall response rate according to RECIST v1.1 criteria, serum markers response and safety. Fifteen patients were included. At a median follow-up of 26.1 months (IQR, 17.7-49.6), median PFS was 17.9 months (95% CI, 11.0-NE), with 1-year PFS and OS rates of 73% and 87%. Safety profile was manageable, with only 13% G3/G4 treatment-related adverse events. Metronomic capecitabine, bevacizumab, and MMC are an active regimen in advanced and progressive PMP and favorably compares with historical series. Pseudomyxoma peritonei is a rare tumor and the role of systemic chemotherapy for advanced or unresectable disease is not defined. Fifteen patients received mitomycin-C, metronomic capecitabine, and bevacizumab as palliative treatment. Median PFS was 17.9 months and treatment was well tolerated. These results compare favorably to previous literature data.