Department of Pathology, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
Ospedale Pediatrico Bambino Gesu (OPBG), and Istituto Ricovero E Cura a Carattere Scientifico, Rome, Italy.
Head Neck Pathol. 2021 Sep;15(3):796-802. doi: 10.1007/s12105-021-01288-7. Epub 2021 Jan 18.
Salivary gland secretory carcinoma (SSC) is a neoplasm with characteristic histologic features, similar to those of secretory carcinoma of the breast. Only a few pediatric SSC cases have been reported, all with ETV6-NTRK3 fusion. We present four new pediatric SSC examples, one with a novel ETV6-RET fusion. Four cases of SSC were diagnosed between 2010 and 2020: 2 boys, 7 and 9 year-old with parotid tumors (1.5 and 1.3 cm, respectively); and two 14 year-old girls: one with a submandibular tumor (2.1 cm), and one with a parotid lesion (1.2 cm). Histologically, all tumors were similar: well-circumscribed lesions composed by mid-size, monotonous cells with eosinophilic and sometimes vacuolated cytoplasm. The nuclei are oval to round with open chromatin and a single nucleolus. There are duct-like structures and microcysts with colloid-like material. Immunohistochemically, tumor cells are positive for S100, CK7, mammaglobin and GATA3. A classic ETV6-NTRK3 translocation was confirmed in the three parotid tumors; an ETV6-RET fusion was demonstrated in the submandibular lesion. All patients underwent complete surgical resection and are alive without tumor recurrence after a follow-up time ranging from one to 4 years. Pediatric SSC is extremely rare but their characteristic morphology and immunohphenotype facilitate their diagnosis. We describe the first pediatric case with the recently reported ETV6-RET fusion. Similar to adult cases, this tumor is morphologically undistinguishable from those carrying the classic ETV6-NTRK3 translocation. Thus, in pediatric cases with morphology suggestive of SSC and negative ETV6-NTRK3 by RT-PCR, other possible fusions should be investigated.
唾液腺分泌性癌（SSC）是一种具有特征性组织学特征的肿瘤，类似于乳腺分泌性癌。仅有少数儿科 SSC 病例报道，均伴有 ETV6-NTRK3 融合。我们报告了 4 例新的儿科 SSC 病例，其中 1 例伴有新型 ETV6-RET 融合。这 4 例 SSC 病例分别在 2010 年至 2020 年期间诊断：2 例为男性，分别为 7 岁和 9 岁，腮腺肿瘤（分别为 1.5cm 和 1.3cm）；2 例为 14 岁女孩：1 例为下颌下腺肿瘤（2.1cm），1 例为腮腺病变（1.2cm）。组织学上，所有肿瘤均相似：界限清楚的病变由中等大小的、单调的细胞组成，细胞胞浆嗜酸性，有时有空泡。细胞核呈椭圆形至圆形，染色质开放，核仁单一。存在导管样结构和微囊，内含胶样物质。免疫组化染色显示，肿瘤细胞阳性表达 S100、CK7、乳球蛋白和 GATA3。在 3 例腮腺肿瘤中证实存在经典的 ETV6-NTRK3 易位；在下颌下腺病变中证实存在 ETV6-RET 融合。所有患者均行完全手术切除，随访 1 至 4 年，无肿瘤复发，均存活。儿科 SSC 极为罕见，但它们的特征性形态和免疫表型有助于诊断。我们描述了首例具有新近报道的 ETV6-RET 融合的儿科病例。与成人病例一样，该肿瘤在形态上与携带经典 ETV6-NTRK3 易位的肿瘤无法区分。因此，在形态学提示 SSC 且 RT-PCR 检测 ETV6-NTRK3 阴性的儿科病例中，应进一步研究其他可能的融合。
