Thoracic Sertoli-Leydig cell tumor: An alternative type of pleuropulmonary blastoma associated with DICER1 variation

Abstract

A 2-year-old boy presented with a large cystic and solid chest mass arising from the lung, radiographically consistent with pleuropulmonary blastoma (PPB). He underwent right lower lobectomy with resection of a well-circumscribed, mixed solid and cystic mass. The solid areas were composed of cords and nests of tumor cells in the myxoid stroma and retiform foci whose pathologic and immunophenotypic findings were consistent with a sex cord-stromal tumor with features of a Sertoli-Leydig cell tumor. Tumor testing showed a pathogenic variant in the DICER1 RNase IIIb hotspot domain. Family history was suggestive of DICER1 germline pathogenic DICER1 variation in absence of a detectable germline variant. He received 12 cycles of chemotherapy with ifosfamide, vincristine, dactinomycin and doxorubicin (IVADo) and surgery with complete response. One year after completion of chemotherapy, imaging studies showed concern for recurrence confirmed by thorascopic biopsy of a pleural-based mass. He is currently receiving cisplatin-based chemotherapy with reduction in tumor size. Review of the literature showed no similar cases; however, review of our pathology files revealed a single similar case of anterior mediastinal Sertoli cell tumor in a 3-year-old girl.

Keywords: DICER1; Sertoli-Leydig cell tumor; pleuropulmonary blastoma; thoracic tumor.

Conflict of interest statement

Conflict of Interest: DAH is founder/investor in ResourcePath LLC. The other authors have no conflicts of interest to disclose.

© 2021 Wiley Periodicals LLC.

Figures

Figure 1.

A. Computed tomography (CT) scan at initial presentation demonstrating a mixed cystic and solid mass. B. Surveillance CT scan performed one year following diagnosis, demonstrating recurrent mediastinal mass and pleural-based lesion. C. Intraoperative photo obtained during thorascopic biopsy of recurrent anterior chest wall pedunculated mass. D. Intraoperative photo obtained during thorascopic excision of anterior mediastinal pleural based mass.

Figure 2.

A. Small cellular nests of tumor surrounded by a pale myxoid stroma. Within the nests, collections of small cells are accompanied by larger eosinophilic cells with features of Leydig cells. B. More cellular areas were composed of small tubules and cords of basophilic cells with features of Sertoli cells and papillary-retiform features. C. Diffuse, intense inhibin immunopositivity is present. D. WT1 nuclear positivity highlighted the nested foci.