ENDOBRONCHIAL GLOMUS TUMOR: AN UNUSUAL LOCATION FOR A RARE MALIGNANCY

Abstract

TOPIC: Lung Cancer TYPE: Medical Student/Resident Case Reports INTRODUCTION: Glomus tumors are rare neoplasms which usually arise from the glomus bodies in the subungual dermis of the hands and feet. Cases of endobronchial glomus tumors present an already rare malignancy in an exceedingly rare location. CASE PRESENTATION: A 76 year-old female who presented with productive cough and progressive dyspnea underwent a CT chest which indicated a 16x14x17 mm right lower-lobe endobronchial mass. Bronchoscopy demonstrated a completely obstructing and vascular appearing mass in right lower lobe which was followed by endobronchial biopsy and incomplete tumor resection. Histological examination confirmed the diagnosis of glomus tumor. Patient was evaluated by radiation oncology and approved for radiation therapy but declined, given symptomatic improvement following partial resection. DISCUSSION: Glomus tumors are rare, typically benign, malignancies that arise from neuromyoarterial glomus bodies, which have a strong predilection for subungual location. These malignancies account for 2% of soft tissue tumors. Rarely, these tumors can occur in extra-cutaneous sites such as bone, gastrointestinal tract and lungs. Most cases of endobronchial glomus tumors are asymptomatic but depending on size and location of tumor, patients may present with dyspnea, wheeze, or other respiratory complaints. Most glomus tumors are benign but malignant characteristics include: >2cm in size, visceral in location, and containing atypical mitotic figures. Glomus tumors are slow growing neoplasms that are characterized as small, uniform, and containing round nuclei with each cell surrounded by basal lamina. CONCLUSIONS: Due to the rarity of extracutaneous glomus tumors reported in the literature their clinical course and prognosis are unknown. Most clinicians recommend surgical resection as definitive treatment but endobronchial therapy such as ablation can be considered. If lesion is intrapulmonary, a sub-lobar resection may be sufficient but lobectomy may be required for large masses that are centrally located. In our case, the patient forwent further treatment given the asymptomatic nature of her post-operative course and opted for serial monitoring for tumor recurrence. This case highlights an exceedingly rare location for a fortunately benign malignancy. REFERENCE #1: Chou T, Pan SC, Shieh SJ, Lee JW, Chiu HY, Ho CL. Glomus Tumor: Twenty-Year Experience and Literature Review. Ann Plast Surg. 2016 Mar;76 Suppl 1:S35-40. doi: 10.1097/SAP.0000000000000684. PMID: 26808758. REFERENCE #2: Valle, Javier Alonso Baena-Del, et al. "Glomus Tumour of the Lung: A Case Report and Literature Review." Cirugía y Cirujanos (English Edition), Elsevier, 20 Apr. 2016, www.sciencedirect.com/science/article/pii/S2444050715000650. REFERENCE #3: Yun, Ju Sik, et al. "Synchronous Primary Glomus Tumor in a Patient with Adenocarcinoma of the Ipsilateral Lung." Thoracic Cancer, John Wiley & Sons Australia, Ltd, May 2019, www.ncbi.nlm.nih.gov/pmc/articles/PMC6501053/. DISCLOSURES: No relevant relationships by Joseph Flynn, source=Web Response No relevant relationships by Stephen Mitchell, source=Web Response No relevant relationships by John Wynne, source=Web Response