Pleuropulmonary Involvement in Pseudomyxoma Peritonei

Abstract

Intrathoracic spread in patients with pseudomyxoma peritonei (PP) is rare. We reviewed 101 patients uniformly treated at our institution for PP of appendiceal origin. In that study, we suggested mucinous carcinoma peritonei (MCP) as the pathologic terminology for all cases of PP. Four patients had pathologically documented pleuropulmonary involvement. We subsequently examined another patient with pleural invasion. Of 5 patients, 3 had low-grade histologic features in the peritoneum; these showed variably proliferative, bland-appearing neoplastic cells arising from low-grade appendiceal mucinous neoplasms. In 2 cases, 1 or more pulmonary parenchymal metastases of low histologic grade developed. The lack of pleural involvement argued against transdiaphragmatic tumor extension. The third patient with low-grade MCP had direct extension through the left diaphragm involving the left pleural and pericardial spaces without pulmonary parenchymal involvement. In the 2 patients with high-grade MCP, right-sided pleural effusions developed. Neither patient had documented injury to the diaphragm. Pleural cytologic examination revealed high-grade adenocarcinoma cells singly, in small clusters, and in large spheres. The smear backgrounds contained wispy mucin. None of the 5 patients developed thoracic lymph nodal metastases. Although rare, mucinous neoplasms from PP may involve the thorax.

Pulmonary Metastasis from Pseudomyxoma Peritonei

“…Extra-abdominal metastasis of PMP is exceptionally rare, but the lung and pleura are the most likely sites in such a case [9]. The majority of pleural metastases were caused by diaphragmatic injury at previous cytoreductive surgery or direct invasion through the diaphragm [13, 14].…”

“…CRS and HIPEC were performed in six out of the eight cases, which were reported more recently [7, 9]. Only CRS was done in one case [8], and appendectomy with radiotherapy was done in another case [10].…”

Pseudomyxoma pleuri as a Surgical Emergency: a Rare Case Report

“…Majority of the patients develop pleural involvement after primary disease and limited cases has been reported with simulatenous presentation. Their pathway of spread is largely speculative [2,4]. In our patient, spontaneous transdiaphragmatic spread is the likely mechanism, as abundance of mucinous material with obvious infiltration of the diaphragm which was evident on exploration.…”

“…Pseudomyxoma with pleural involvement, which is also described as Pseudomyxoma pleuri, is an uncommon presentation. The literature is sparse and largely case report based [2][3][4]. Majority of the patients develop pleural involvement after primary disease and limited cases has been reported with simulatenous presentation.…”

Significance of signet ring cells in high-grade mucinous adenocarcinoma of the peritoneum from appendiceal origin

“…However, as shown by Bradley et al, all forms of pseudomyxoma peritonei are malignant in the traditional sense. Furthermore, cases of DPAM were shown to metastasize to the thorax, an attribute that demonstrates the true malignant nature of this process [3]. …”