Primary extragenital endometrial stromal sarcoma of the lung: first reported case and review of literature

Abstract

Background: Endometrial stromal sarcomas arising in extrauterine and extraovarian sites, in the absence of a primary uterine lesion are quite rare, especially in the absence of endometriosis. They usually present as an abdominal or pelvic mass lesion.

Case presentation: In 2007, a 45-year-old woman underwent total hysterectomy for in situ squamous cell carcinoma of the cervix. In 2014, an upper left pulmonary lobectomy was performed for a mass, which was provisionally diagnosed as primary carcinosarcoma of the lung. A second histological revision of the lung surgical specimen was performed in the Pathology Unit of our Institute. After extensive immunohistochemical analyses, the preferred diagnosis was spindle-cell sarcoma, consistent with high-grade extragenital endometrial stromal sarcoma (EESS). A review of all slides of the hysterectomy specimen confirms the original diagnosis: no evidence of stromal tumor was found. Afterwards, the patient developed multiple and metachronous pulmonary lesions and a scapular soft tissue mass, which showed the same morphophenotypic features of the first lung mass. The patient was treated with antiblastic therapy, surgical resection and radioablation, when appropriate. To date, the patient has no signs or symptoms.

Conclusions: The authors present the first case of primary EESS arising in the lung with no association with endometriosis published to date. Detailed clinical history and follow-up are also described. Moreover, extensive literature review is reported, along with differential diagnoses, immunohistochemical and molecular findings, pathogenetic hypotheses and treatment options. The knowledge of EESS potential extrauterine location and of its peculiar morphophenotypic aspects are required for a correct diagnosis, and for choosing the most suitable treatment.

Keywords: Case report; Extragenital endometrial stromal sarcoma; Immunohistochemistry; Lung.

Fig. 1

Thoracic CT scan showing a mass (50 mm of maximum diameter) in the upper left lobe

Fig. 2

a, b Panoramic view of the pulmonary lesion showing uniform spindle cells arranged in a fascicular pattern; alveolar epithelium is focally entrapped by the neoplastic cells (H&E, 100×); c, d some small thinwalled blood vessels resembling spiral arterioles of late secretory endometrium were unevenly distributed among the stroma (H&E, 100×); b, d, neoplastic cells show moderate atypia and foci of hyaline-type necrosis, in a background of fibromyxoid stroma); d, the tumor cells had oval to plump spindle-shaped nuclei with finely granular chromatins, inconspicuous nucleoli, and amphophilic cytoplasms (H&E, 200×)

Fig. 3

Neoplastic cells showed patchy and intense immunoreactivity for CD10 (a, 100×), diffuse vimentin staining (b, 100×), negative staining for H-Caldesmon (positive control staining in small vessels;upper left) (c, 100×), negative staining for TTF-1 (positive nuclear staining in the entrapped epithelial alveolar elements; right) (d, 100×), moderately diffuse nuclear staining for estrogen receptor (e, 200×), moderately diffuse nuclear staining for progesterone receptor (f, 200×)

Fig. 4

Leiomyoma with classic morphology from previous hysterectomy specimen, showing intersecting fascicles of cigarshaped, spindle cells with eosinophilic cytoplasm (a, 200×); CD10 negative immunostaining (b, 200×); positive nuclear staining for estrogen receptor (c, 200×), positive nuclear staining for progesterone receptor (d, 200×)