LAUSR

Pseudomyxoma peritonei (PMP) is a disorder characterized by an intra-abdominal accumulation of mucin secondary to the growth of neoplastic mucin-secreting cells on peritoneal surfaces [1, 2]. PMP is a rare condition with an estimated incidence of one to two cases per million per year [3, 4]. Patients have an average age of 53 years at the time of diagnosis, being more commonly seen in females [5, 6]. In most cases, the neoplasm originates in the appendix and later spreads through the wall of the appendix into the peritoneal space [7, 8]. Reproduction and aggregation of free and implanted tumor cells lead to a progressive peritoneal mucinous tumor and ascites [9]. In other reported cases, the primary tumor origin has occasionally developed in other organs including the ovary, colorectum, gallbladder, stomach, pancreas, urachus, fallopian tube, lung, and breast [10, 11]. Initial presentation varies and consists of unspecified signs and symptoms that relate to the progression of the disease [12]. These include increased abdominal girth, an appendicitis-like syndrome, a new-onset hernia, presence of a pelvic mass, or nonspecific abdominal or pelvic pain [8, 13, 14]. Progressive accumulation of mucinous material gradually fills and can compress vital organs within the peritoneal cavity, which can result in abdominal distention, ascites, bowel obstruction, and nutritional compromise [8, 15, 16]. In 1995, two diagnostic categories were suggested by Ronnett et al. [17], which correlated the prognosis with the histological features (Table 1). These included disseminated peritoneal adenomucinosis (DPAM) and peritoneal mucinous carcinomatosis (PMCA). DPAM consisted of peritoneal lesions composed of abundant extracellular mucin containing scant simple to focally proliferative mucinous epithelium with little cytologic atypia or mitotic activity, with or without an associated appendiceal mucinous adenoma. PMCAwas composed of peritoneal lesions containing more abundant mucinous epithelium with the architectural and cytologic features of carcinoma, with or without an associated primary mucinous adenocarcinoma [17]. In 2010, the World Health Organization (WHO) and the American Joint Committee on Cancer (AJCC) also proposed a pathological classification regarding a histological distinction between a low-grade or high-grade lesion (Table 1) [8]. This criterion is based on the histogenesis, molecular and cytological features [8]. Low-grade mucinous adenocarcinoma is characterized by mucin pools with low cellularity (< 10%), bland cytology, and non-stratified cuboidal epithelium [8]. High-grade mucinous adenocarcinoma contains mucin pools with cellularity, moderate/severe cytologic atypia, and signet ring morphology with desmoplastic stroma [8]. Studies correlating the histological classification to the prognosis of the disease determine that those with DPAM have much better outcomes when compared to patients with high-grade PMCA tumors [8, 18]. Treatment has generally consisted of repeating interventions of debulking procedures; however, long-term survival and possibility of cure have had limited expectations [7, 11]. Proposed treatment in the setting of peritoneal involvement consists of complete cytoreduction surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) [19, 20]. In this aggressive treatment approach, surgery aims to make a complete macroscopic cytoreduction and lysis of * Ángel M. Rodríguez [email protected]