Solitary fibroleiomyomatous hamartoma of the lung in a patient without a pre‐existing smooth‐muscle tumor

Abstract

A solitary well-demarcated tumor was found in the left lung of a 53-year-old man. It was located in the posterior region of the lower lobe just adjacent to, but apart from, the pleura. It was resected by video-associated thoracic surgery. Macroscopically, the tumor was a whitish solid nodule without hemorrhage or necrosis, and it was 1.5 cm in diameter. Histologically, the tumor consisted of a proliferation of fibromuscular tissue in interlacing fascicles in which many tubular or cleft-like epithelial inclusions were involved. The epithelial inclusions showed cystic changes with goblet cell metaplasia in part, but no atypical changes. Other mesenchymal components such as cartilaginous, myxomatous or adipose tissues were not seen. The patient had no history of neoplasm, including smooth-muscle tumor. Thus, we diagnosed this tumor as a "true" fibroleiomyomatous hamartoma, as distinct from so-called fibroleiomyomatous hamartoma or benign metastasizing leiomyoma, which are usually found in the lungs of women who have had hysterectomies, as multiple fibromuscular nodules. We report here this rare case and we review and discuss published reports of fibromuscular tumors of the lung.

Adenomyomatous Hamartoma of Lung Mimicking Benign Mucinous Tumor in Fine Needle Aspiration Biopsy

“…We found such cases in the English literature designated as adenomyomatous hamartoma, 5 fibroleiomyomatous hamartoma 6 and adenoleiomyomatous hamartoma, 7 suggesting that it belonged to the hamartoma category. Histologic differential diagnoses include benign metastasizing leiomyoma, primary leiomyoma, and cystadenomatous hamartoma.…”

Endobronchial fibroleiomyomatous hamartoma: a diagnostic pitfall

“…On the other hand, they have been thought to arise primarily from the lung and in this case are called fi broleiomyomatous hamartomas. 5 The patients may be asymptomatic, with the mass incidentally detected on chest radiography; or there may be symptoms of bronchial compression/obstruction. These tumors are well delineated on CT scans.…”

“…Histopathologically, pulmonary hamartoma consists of an admixture of cartilage, loose connective tissue, fat, and epithelial aggregates in varying proportion. 5 The presence of an endobronchial tumor obstructing the respiratory tract and producing symptoms merits its excision. Tumors with preoperative benign histology are amenable to resection through rigid and fl exible bronchoscopy using laser or electrocautery.…”

Is a Miliary Chest Pattern Always Indicative of Tuberculosis or Malignancy?

“…In general BML lesions have the same histological appearance as the initial uterine leiomyoma [4,12] . The histological differential diagnosis of pulmonary smooth muscle nodules includes BML, primary leiomyoma or leiomyosarcoma, metastatic leiomyosarcoma, pulmonary hamartoma, leiomyomatous hyperplasia and lymphangioleiomyomatosis [6,[13][14][15] , in which, however, the proliferating cells express HMB-45. Reported treatment methods include surgical resection of the nodules if possible, hysterectomy and bilateral oophorectomy, chemotherapy, progesterone and medical castration using luteinizing hormone-releasing analogue or the appropriate combination of them [2,8,16] .…”

“…The disease is extremely rare with a controversial pathogenesis [4,14] that has to be kept in mind in every case of a pulmonary lesion presenting clinically with a miliary pattern and containing histologically smooth muscle nodules.…”