Well-differentiated papillary mesothelioma found incidentally with concurrent struma ovarii: A case report.

This is the first report of well-differentiated papillary mesothelioma (WDPM) found concurrently with struma ovarii. These rare tumors have no know association, and are considered benign, though malignant transformation of WDPM has been described. After treatment of WDPM, follow-up surveillance has been suggested in the literature, though a method has not been described and an evidence base is lacking. Pre-operative imaging by computed tomography and ultrasound did not identify the WDPM, calling into question the role of imaging-based follow-up. Furthermore, malignant transformation has been reported only outside of the typical 5-year follow-up window. The authors of this case report suggest rationalization of follow-up of WDPM, acknowledging the risks and unknown harms of scheduled imaging follow-up.