Diagnosis Of Mammary Analogue Secretory Carcinoma Research Articles

Mammary-analog secretory carcinoma in children: Surgery or TRK inhibitors first?

We report two cases of pediatric mammary-analog secretory carcinoma (MASC), a male operated on at age 8 and a female operated on at 12, who are in remission 2years after surgery. The diagnosis of MASC was challenging and established by identifying the ETV6::NTRK3 fusion transcript in both cases. Given the excellent results of TRK inhibitor treatments in adult MASC and pediatric tumors expressing an ETV6::NTRK3 fusion, they should probably be prescribed as first-line treatment in cases requiring surgery with foreseeable serious sequelae or metastatic disease.

An FNA pitfall: Mammary analog secretory carcinoma mistaken for acinic cell carcinoma due to cytoplasmic granules

In the salivary gland, a key differential feature of Mammary analog secretory carcinoma (MASC) from acinic cell carcinoma (ACC) is the lack of cytoplasmic granules. We report a case of a parotid mass incorrectly diagnosed on fine needle aspirate as acinic cell carcinoma due to many cells with basophilic granules suggesting serous acinar differention. Tumor resection revealed a tumor consistent with low grade adenocarcinoma that had eosinophilic, microvacuolar cytoplasm with distinct basophilic granules staining with PASD and mucicarmine. The diagnosis of MASC was confirmed with stains for GCDF-15, mammoglobin, and S100 and FISH consistent with a t(12;15) translocation. Relying on the absence of cytoplasmic granules as a feature to distinguish ACC from MASC is a diagnostic pitfall.

Mammary analogue secretory carcinoma (MASC) of salivary gland in four Mexican patients.

The Clinco-pathological, immunohistochemical and molecular findings of four cases of Mammary Analogue Secretory Carcinoma (MASC) of salivary glands found in Mexico are described. The cases were extracted from 253 salivary gland tumors from a single institution in Mexico City. The 85 candidates for initial selection were: low grade mucoepidermoid carcinoma (MEC) (N=70 ), acinic cell cancinoma (AciCC) (N=14), papillary cystadenocarcinoma (N=1), and adenocarcinoma NOS (N=0). Tumors with some histological features consistent with MASC (N= 17, 6.7%) were studied by immunohistochemistry for mammaglobin, STAT5, and S-100 protein and four cases were positive (1.5%), thus the diagnosis of MASC was established, and these were submitted for molecular studies for ETV6-NTRK3. Fusion gene was demonstrated in three cases, two had been erroneously diagnosed as poorly granulated AciCC, and one as low grade MEC with microcystic pattern. Female gender predominated (3:1); one occurred in the parotid, two in minor salivary glands and one in the submaxillary gland; infiltrating borders, atypical mitosis and lymph node metastases were seen in the parotideal tumor. Two patients with major salivary gland tumors are alive and well at 10 and 20 months respectively, the two patients with minor salivary gland tumors are lost. It can be concluded that is important to think in MASC in poorly granulated AciCC and low grade MEC with microcystic pattern. Immunohistochemisty studies confirm the diagnosis, preferentially supported by molecular studies. MASC may follow aggressive behavior or transform into a high grade neoplasm. Key words:Acinic cell carcinoma, ETV6-NTRK3, Mammary Analogue Secretory Carcinoma, secretory breast carcinoma.

Cytopathological features of mammary analogue secretory carcinoma—Review of literature

Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland tumor that morphologically resembles mammary secretory carcinoma and carries the identical ETV6-NTRK3 fusion gene. We report a surgical resected case of MASC in the parotid gland of a 41-year-old man. The cytological smears of a preoperative fine-needle aspiration showed many sheets and crowded clusters of monotonous epithelioid cells with mild atypia, suggestive of monomorphic tumor. Histologically, the tumor was composed of cuboidal cells with follicular, tubular, and solid structures, reminiscent of acinic cell carcinoma of follicular variant, which had been previously classified. This case had ETV6-NTRK3 fusion gene transcript confirmed by fluorescence in situ hybridization and reverse transcription polymerase chain reaction. In the cytological and histopathological diagnosis of monomorphic tumor of salivary gland, MASC needs to be taken into consideration as a differential diagnosis. Further immunohistochemical and gene analyses are needed in diagnosis of MASC.