A first case report of clinical response to targeted therapy in a patient with primary myoepithelial carcinoma of the lung harboring EGFR exon 19 deletion

Clinical, laboratory, pathological, and radiological characteristics and prognosis of patients with pulmonary salivary gland-type tumors

PURPOSE

Primary pulmonary salivary gland-type tumor (PSGT) included two main subtypes, pulmonary adenoid cystic carcinoma (PACC) and pulmonary mucoepidermoid carcinoma (PMEC). The purpose of this study was to compare the similarities and differences between these two subtypes and to identify independent risk factors for the prognosis of PSGT patients.

METHODS

This study screened patients with a pathological diagnosis of PSGT in Beijing Chaoyang Hospital between 2010 and 2021. The clinical, pathological, radiological, laboratory test, and other characteristics were collected, and t, nonparametric and chi-squared tests were used to compare the differences in clinical characteristics of the two subtypes. COX univariate and multivariate analyses were used to explore prognostic-related risk factors.

RESULTS

A total of 62 patients with PSGT were included in our center over a 12-year period. There were 26 PMEC patients and 36 PACC patients. There were differences in the clinical, pathological, and radiological features of the two tumor subtypes. Univariate analysis showed that weight loss, chemotherapy, white blood cells, lymphocytes, red blood cells, total protein, and total bilirubin might be related to the prognosis in PSGT patients. Multivariate results showed that lymphocytes (p = 0.031), red blood cells (p = 0.047), total protein (p = 0.032), and total bilirubin (p = 0.010) were independent prognostic risk factors. Chemotherapy (HR 4.452; 95% CI 1.723-11.503; p = 0.002) might be associated with progression-free survival (PFS).

CONCLUSION

The two subtypes of PSGT had significantly different clinical, laboratory, pathological, and radiological features. However, there was no significant difference in the prognosis of patients with PMEC and PACC subtypes. Cox univariate and multivariate analyses showed that levels of lymphocytes, erythrocytes, total protein and total bilirubin in the peripheral blood of PSGT patients might be related to patient overall survival. Chemotherapy might also be associated with PFS.

Carboplatin, pemetrexed, and pembrolizumab was effective for primary salivary gland-type lung adenocarcinoma diagnosed due to esophageal stricture: A case report

Primary salivary gland‐type tumors of the lung are rare, accounting for <1% of all lung tumors. There are few reports on chemotherapy for the treatment of primary salivary gland‐type tumors of the lung. The patient in this report was a 71‐year‐old woman who presented with a chief complaint of dysphagia. Upper gastrointestinal endoscopy revealed an esophageal stricture, but biopsy showed no malignancy. Chest computed tomography (CT) showed carcinomatous lymphangiomatosis and a nodule in the right lung. Bronchoscopy showed a rough mucous membrane of the central bronchi, while biopsy showed adenocarcinoma. The patient was diagnosed with bronchogenic adenocarcinoma and received carboplatin, pemetrexed, and pembrolizumab, which alleviated the esophageal stricture and cancerous lymphangiopathy. However, the adenocarcinoma progressed, and she subsequently received several rounds of chemotherapy. One year after diagnosis, the patient died, and pathological autopsy revealed primary salivary gland‐type tumors of the lung.

Primary high-grade myoepithelial carcinoma of the lung: A study of three cases illustrating frequent SMARCB1-deficiency and review of the literature

Primary myoepithelial carcinoma of the lung is exceptionally rare and, hence, remained poorly characterized. We present 3 tumors affecting 2 males and 1 female aged 60 to 84 years. Tumor size ranged from 4 to 10 cm. All presented as well circumscribed non-encapsulated peripheral solitary masses. One patient died postoperatively. The other two were lost to follow-up. Histologically, all tumors were high-grade with predominance of myxoid/chordoid (2) and rhabdoid (1) pattern. Immunohistochemistry (IHC) showed reactivity with vimentin, pankeratin, EMA and smooth muscle actin. Two tumors were SMARCB1-deficient (one with additional loss of SMARCA2 and PBRM1). RNA sequencing revealed no gene fusions. Review of reported cases (total: 16) showed that pulmonary myoepithelial carcinoma affects both sexes equally at a median age of 60 years (24-84), presents predominantly as peripheral masses (69%) in the lower lobes (66%) of smokers (70%) with a median size of 6 cm (1.5-13), and originates as high-grade de novo carcinoma. Forty percent of patients died of disease at a median of 12.5 months (0 to 62). Only 40% of patients were disease free at last follow-up (median, 9.5 months). Prominent lobulation and myxoid stroma were frequent histological features. Most tumors displayed variable combinations of epithelioid, spindle, plasmacytoid, clear, ovoid or round cells. Three of 6 tumors subjected to different RNA panels showed EWSR1 rearrangements (fused to PBX1, ZNF444 or to unknown partner). Two of 3 tumors lacking gene fusions were SMARCB1-deficient (both showed secondary EWSR1 FISH abnormalities due to 22q deletion). Primary pulmonary myoepithelial carcinoma is a rare aggressive malignancy that recapitulates its soft tissue and salivary counterpart. Exclusion of metastasis from other primaries is mandatory and can only be achieved by detailed clinical history and imaging.