[1837] Sarcomatoid Peritoneal Mesothelioma: Clinicopathologic Correlation of 13 Cases

EN Pavlisko, VL Roggli. Duke University Medical Center, Durham, NC

Background: Peritoneal mesothelioma is rare and the sarcomatoid variant is more infrequent. Several case series have described the morphologic features of sarcomatoid peritoneal mesothelioma (SPe); however, the clinicocopathologic features are not well characterized.
Design: We reviewed our database of 2859 mesothelioma cases, of which 2524 (88%) were pleural and 335 (12%) were peritoneal. Of the peritoneal mesotheliomas, 252 (75%) were epithelioid, 70 (21%) were biphasic, and 13 (4%) were sarcomatoid variant.
Results:

Table 1: Demographics, Pathologic Findings, and Fiber Analysis

Case	Age	Sex	Occupation/Exposure	Parietal Pleural Plaques	Asbestosis	Tumor Type	Asbestos Content
1	70	M	Johns-Manville, many yrs.	Y	Y	DSPe	ND
2	74	M	Shipyard electrician, 16 yrs; Power plant worker, 21 yrs.	Y	ND	SPe LHC	ND
3	66	M	Johns-Manville, 39 yrs.	Y	Y	DSPe	ND
4	70	M	Merchant marine seaman, 23 yrs.	ND	ND	SPe	ND
5	65	F	HHC; Husband, shipyard worker	N	N	SPe	Elevated
6	69	M	Shipyard insulator, 49 yrs.	Y	ND	SPe	ND
7	70	M	ND	N	Y	SPe	Elevated
8	59	F	HHC; Husband, construction worker, 42 yrs.	ND	ND	SPe	WNL
9	59	M	Construction, 31 yrs.	ND	Y	SPe	ND
10	49	F	HHC; Husband, power plant	ND	ND	SPe H	WNL
11	54	M	Janitor	ND	ND	SPe	ND
12	53	M	ND	N	ND	SPe H	ND
13	72	M	Electrician, 24 yrs	N	ND	SPe	ND

HHC, household contact; SPe, sarcomatoid peritoneal mesothelioma; DSPe, desmoplastic SPe; LHC, lymphohistiocytic; H, heterologous elements; ND, no data; WNL, within normal limits


Conclusions: To our knowledge, this is the first large series reporting the clinicopathologic features of SPe. The average age at diagnosis was 65.5 years and there was a male predominance (M:F = 3:1). All cases stained positive for cytokeratins, and two contained heterologous elements. Seven cases had objective markers of asbestos exposure (plaques, asbestosis, and/or elevated lung asbestos content), and two additional cases (4, 13) had occupations that are strongly associated with mesothelioma. Two cases with alleged household contact exposures (8, 10) could not be confirmed by lung fiber analysis. SPe is a rare variant of mesothelioma that is frequently related to asbestos exposure (9/13 cases).
Category: Pulmonary

Monday, March 22, 2010 2:15 PM

Platform Session: Section E, Monday Afternoon