Predictors of Progression of Appendiceal Mucinous Neoplasm to Pseudomyxoma Peritonei

Abstract

Appendiceal mucinous neoplasm (AMN) can present with a spectrum of disease. Predicting factors in development of pseudomyxoma peritonei (PMP) from AMN could aid in management and treatment. The aim of this study was to determine factors predictive of PMP from AMN. This was a retrospective multicenter study of all patients diagnosed with AMN from 2006-2017. Diagnosis of PMP was compared by (1) patient demographics, (2) tumor characteristics, and (3) surgery. Secondary end points were disease-specific survival (DSS) and overall survival (OS). One-hundred thirty-eight patients with AMN were identified. Thirty-six patients (26.1%) had a ruptured appendix at presentation, and 12 patients (8.7%) were diagnosed with PMP during the study period. Eight patients presented with PMP at the time of surgery. No demographic factors were predictive of PMP. Operative approach and extent of initial resection did not correlate with PMP. Tumor rupture at presentation was the only factor associated with PMP, though only 14% of patients who presented with simple rupture eventually progressed to PMP. OS was not different between those who were diagnosed with PMP and those who were not. DSS was significantly lower for the group diagnosed with PMP ( P = .007). Tumor rupture at presentation did not influence OS or DSS. The only factor found to be significantly associated with PMP was tumor rupture at presentation. Diagnosis of PMP did not affect OS but did lead to decreased DSS. In conclusion, though a majority of patients who presented with rupture did not go on to develop PMP, tumor rupture at presentation was the only factor significantly associated with PMP. Diagnosis of PMP did not affect OS at 5 years. In patients with AMN who present with a ruptured appendix on final pathology, we recommended continued surveillance, though overall risk of PMP is relatively low.

Clinicopathological Characteristics of Primary Appendiceal Mucinous Neoplasm and Recurrence After Radical Resection

“…It was revealed that age, tumor rupture at presentation, tumor size, and CA19-9 levels might be associated with the progression of PMP. We found that tumor rupture was a risk factor leading to PMP in patients with AMN, which was supported by other studies ( 34 ) indicating tumor rupture at presentation was the only factor significantly associated with PMP. The follow-up data (median: 19 months, ranging from 2 to 47.5 months) showed no significant difference in the OS between patients with non-LAMN and LAMN, and between patients with PMP and without PMP.…”

Lower Gastrointestinal Bleeding Secondary to Appendiceal Mucinous Neoplasm: A Report of Two Cases and a Review of the Literature

“…In most cases with suspected appendicular mucinous neoplasms, appendectomy is recommended, and in the worst-case scenario, cecectomy or ileocecectomy is performed to avoid the morbidity of a right hemicolectomy. This is usually sufficient for low-grade mucinous neoplasms, where the histopathological report will guide subsequent therapeutic decisions, with the need for right hemicolectomy in 20% of cases due to reports of high-grade neoplasms [12][13][14][15].…”

Retrospective Review of Outcomes in Non-Invasive Mucinous Appendiceal Neoplasms with and without Peritoneal Spread: A Cohort Study

“…Although not all patients with NI-MAN rupture progress to PMP, macroscopic or microscopic dissemination of mucin to the peritoneum increases the risk of PMP recurrence. In a study by Sueda et al [ 24 ] in 136 patients with NI-MAN, tumor rupture on presentation was associated with the development of PMP. With the exception of patients with established peritoneal disease at the time of index surgery, 14% of patients with ruptured appendix subsequently developed PMP.…”