The cytomorphologic spectrum of salivary gland type tumors in the lung and mediastinum: A report of 16 patients

Abstract

In the lung and mediastinum, salivary gland type tumors (SGTTs) can occur as either primary tumors or metastases from tumors arising in the major or minor salivary glands. This study reviewed the cytology cases of SGTTs in the lung and mediastinum diagnosed over a six-year period at our institution. The specimens included a total of 22 exfoliative or aspiration cytology specimens identified in 16 patients. Two of the cases were primary tumors: adenoid cystic carcinoma (ACC) of the trachea and mucoepidermoid carcinoma (MEC) of the thymus. The remaining 20 tumors were metastases from the parotid, submandibular gland, tongue, nasal cavity, or soft palate. Eight of the 16 patients (50%) had a diagnosis of ACC, four (25%) had salivary duct carcinomas, two (12.5%) had MECs, one (6.25%) was a basaloid tumor, and one (6.25%) was polymorphous low grade adenocarcinoma. In our series, these SGTTs were more commonly metastatic in the lung or mediastinum (87.5% of the patients), and the most common histological subtype was ACC, followed by SDC. This study also illustrates the cytomorphologic features and diagnostic pitfalls of these unusual SGTTs.

HER2/HER3‐positive metastatic salivary duct carcinoma in the pleural effusion: A case report

“…reported that cytological findings of SDC in lung metastasis showed cohesive clusters of intermediate to large size with pleomorphic nucleus and glassy cytoplasm in a necrotic background. 7 These cytological findings were similar to those in our present case, however in our case we needed to distinguish primary lung adenocarcinoma from metastatic SDC, because SDC has a wide cytomorphologic spectrum. 9 ICC for AR antibody is a useful diagnostic tool to distinguish metastatic SDC from primary lung adenocarcinoma, because AR is highly expressed in approximately 80% of SDC, 9 but is only expressed in approximately 3.0% of primary lung adenocarcinoma.…”

“…In cytology, bronchial brushing smears showed small sheet clusters in a slightly necrotic background, which was typical feature of adenocarcinoma. Monaco et al reported that cytological findings of SDC in lung metastasis showed cohesive clusters of intermediate to large size with pleomorphic nucleus and glassy cytoplasm in a necrotic background . These cytological findings were similar to those in our present case, however in our case we needed to distinguish primary lung adenocarcinoma from metastatic SDC, because SDC has a wide cytomorphologic spectrum .…”

“…6 It is known that various carcinomas metastasize to the lung, and that metastasis to the lung from salivary gland cancer is rare. 7 To our knowledge, one case of metastatic SDC in the pleural fluid has been reported in the literature, 8 however, the HER family has never been described in the pleural effusion cytology of metastatic SDC. Histological findings of lung metastatic SDC in our small biopsy tissue sample showed a trabecular or small nested growth pattern, whereas the typical SDC cribriform pattern with central necrosis was not seen.…”

Polymorphous low-grade adenocarcinoma: A case series and determination of recurrence

“…The rate of recurrence of tumors presenting in parotid, submandibular, or sublingual glands was 36.4% and was not statistically significant ( P = .41) compared to the recurrence rates at all other sites of 24.2%. Distant metastasis were identified in the lungs and the liver …”

Pleural fluid metastases of salivary duct carcinoma: A case report and review of the literature

“…Occasional case reports exist of adenoid cystic carcinoma metastasizing to the pleural fluid,[91011] as well as a rare case of benign metastasizing pleomorphic adenoma[12] and a case of mucoepidermoid carcinoma involving peritoneal and pericardial fluid. [913] However, this appears to be the first case report of metastatic SDC in pleural fluid.…”