Glomus tumour: a rare differential diagnosis of bronchial obstruction in a smoker

Primary pulmonary glomus tumor of uncertain malignant potential: A case report with literature review focusing on current concepts of malignancy grade estimation

We report a 38-year-old woman with a left lung tumor presenting as obstructive pneumonia. Bronchoscopic examination revealed a polypoid tumor filling the left main bronchus. The tumor was partially resected by a snaring procedure for diagnostic purposes. Microscopic examination revealed a submucosal tumor located underneath normal bronchial epithelium. The tumor was composed of sheets of uniform oval to cuboidal cells encompassing numerous blood vessels. Immunohistochemically, the tumor cells exhibited smooth muscle markers, but were negative for neuroendocrine markers. The diagnosis of primary pulmonary glomus tumor was therefore made. Subsequent bronchoscopic intervention allowed us to pin-point the origin of the tumor: superior segmental B^6a/b. She underwent a left lower lobe superior segmental resection successfully. Glomus tumors are relatively rare soft tissue tumors, and those of bronchopulmonary origin are exceedingly rare clinical condition. Among primary lung tumors, the carcinoid tumor is a mimic of the glomus tumor, and differentiating these tumors is known to be difficult, especially using small biopsy samples. In the present case, a large tissue sample obtained by bronchoscopic snaring was quite useful for the correct preoperative diagnosis. Because of the disease rarity, malignancy grade estimation of visceral glomus tumors has not been clearly addressed. Recently, the histopathological diagnostic criteria for malignant glomus tumors was defined in the WHO classification of soft tissue and bone tumors 4th edition. Here we also reviewed the literature on primary bronchopulmonary glomus tumors with special attention to the current concept of malignancy grade estimation.

[Glomus tumour of the lung: a case report and literature review]

BACKGROUND

Glomus tumours are neoplasms arising from cells of the neuromyoarterial glomus bodies, which almost always occur in a subungual location. A lung location is extremely rare, with few cases reported in the literature.

CLINICAL CASE

The case is presented of a 33 year-old male, with non-productive cough, dyspnoea at rest, intermittent fever, and mild pain in rib cage. A chest radiograph showed a consolidation in the left lung, and computed tomography revealed a lesion in the hilum that extended to the bronchus of the lingula obstructing, and causing post-obstructive pneumonia. A biopsy was obtained by rigid bronchoscopy biopsy, which showed a well circumscribed tumour constituted by intermediate-sized cells, and abundant cytoplasm that are arranged in a pattern surrounding numerous thin-walled blood vessels, with no pleomorphism, significant mitotic activity or necrosis. Immunohistochemistry revealed diffuse positivity with smooth muscle actin, vimentin, caldesmon; focal reactivity with desmin and CD117, CD34 highlights the vascular pattern. Ki67 proliferation rate was 1%. Synaptophysin, EMA and cytokeratin cocktail were negative, making the diagnosis of glomus tumour.

CONCLUSIONS

Glomus tumours are rare neoplasms that usually appear in the dermis and subcutaneous tissue, where it is common to find glomus bodies. Occasionally glomus tumours can occur in extra-cutaneous sites such as the gastrointestinal tract, bone and respiratory system, with this case being a new case of rare lung location.

Glomangioma of the trachea: A case report and literature review

A 44-year-old male presented with progressing cough, dyspnea and hemoptysis due to a tracheal tumor involving the posterior wall of the lower trachea, with severe airway obstruction and coagulopathy. Consequently the patient underwent segmental resection of the trachea with an end-to-end anastomosis. Twenty months after treatment there remained no evidence of endobronchial recurrence at bronchoscopy or imaging studies. The diagnosis was benign tracheal glomus tumor (GT) which is an exceedingly rare mass lesion in the trachea. There are three subtypes: GT proper, glomangioma and glomangiomyoma. The present study describes the clinical and pathological features of glomangioma through a case report and literature review. To the best of our knowledge, this is the fifth report of glomangioma subtype arising from the trachea.