Sweat-gland carcinoma with neuroendocrine differentiation (SCAND): a clinicopathologic study of 13 cases with genetic analysis.

Low-grade neuroendocrine carcinoma of the skin (LGNECS) was proposed in 2017 as a new primary cutaneous neoplasm with neuroendocrine differentiation; however, it is not yet well known due to its rarity. Herein, we perform a detailed clinicopathologic analysis of 13 cases as well as panel DNA sequencing in three cases. The study included 12 males and 1 female with a median age of 71 (43-85) years. All lesions occurred on the ventral trunk. The mean tumor size was 2.2 (0.8-11.0) cm. The histopathology resembled that of well-differentiated neuroendocrine tumors (NETs) in other organs, but intraepidermal pagetoid spreading was seen in 8 (61.5%) cases and stromal mucin deposits in 4 (30.8%). Immunoreactivity for CK7, CK19, EMA, BerEP4, CEA, chromogranin A, synaptophysin, INSM1, GCDFP15, GATA3, ER, and bcl-2 were present in varying degrees in all tested cases. PTEN c.165-1G>A splice site mutation was detected by panel sequencing in one case, and GATA3 P409fs*99 and SETD2 R1708fs*4 in another case. Lymph node metastasis was seen significantly in cases with tumor size >2.0 cm [8/8 (100%) vs. 1/5 (20%)]. All three cases with size >3.0 cm were in unresectable advanced-stage [3/3 (100%) vs. 1/10 (10%)], and two of the three patients succumbed to the disease. The two cases of death revealed mild nuclear atypia (mitosis: 1/10 HPFs) and moderate nuclear atypia (2/10 HPFs). Thus, tumor size would be a better prognostic factor than nuclear atypia, mitotic count, and Ki67 index, unlike in NETs. These clinicopathologic and immunohistochemical features would represent the characteristics as skin adnexal tumors with apocrine/eccrine differentiation rather than NETs; therefore, we rename it as sweat-gland carcinoma with neuroendocrine differentiation (SCAND).

Rapid and dramatic responses to dabrafenib and trametinib in BRAF V600E-mutated lung adenocarcinoma.

V-raf murine sarcoma viral oncogene homologue B1 (BRAF) is a proto-oncogene that regulates cell proliferation and survival. BRAF V600E-mutated lung cancer has aggressive characteristics and is resistant to chemotherapies. Combination of BRAF-specific inhibitor dabrafenib and mitogen-activated protein kinase kinase (MEK) inhibitor trametinib is the standard treatment for BRAF V600E-mutated lung cancer. We report a case of BRAF V600E-mutated lung adenocarcinoma, which presented with respiratory distress due to deterioration of advanced cancer. The tumour responded rapidly and significantly to BRAF/MEK inhibitors, and the patient's symptoms improved within 2 weeks. BRAF/MEK inhibitors are effective treatment in BRAF-mutated lung cancer even under critical conditions.

Case of low-grade neuroendocrine carcinoma of the skin presenting metastases to lymph nodes and peritoneum.

A 61-year-old Japanese man had a gradually growing, red-colored nodule in his umbilicus from 3 years ago. He had no symptoms such as hot flush, diarrhea or wheezing. Computed tomography detected a 3.0 cm × 3.0 cm enhanced nodule on the umbilical portion, inguinal and axillary lymph node swelling, and peritoneal nodules. Upper and lower gastrointestinal endoscopy and cystoscopy did not show any other tumor. We resected the umbilical nodule and subjected the inguinal lymph node and peritoneal nodule to biopsy. Histopathological findings indicated that the cutaneous lesion was composed of variously sized nests that included small, monomorphic, round to polygonal cells, mainly in the dermis to the peritoneum. Mitotic figures were scant. The inguinal lymph node and peritoneal nodule were positive for metastasis. Immunohistochemistry was diffusely positive for cytokeratin (CK)-7, CD56, chromogranin A, synaptophysin, estrogen receptor-α, progesterone receptor, GATA3 and carcinoembryonic antigen, and focally positive for mammaglobin and gross cystic disease fluid protein 15. The Ki-67 labeling index was 1.5%. The patient was diagnosed with a case of low-grade neuroendocrine carcinoma of the skin (LGNECS) occurring on the umbilicus. This case exhibited distant peritoneal metastasis, as well as inguinal and axillary lymph node metastases; however, the patient is alive without chemotherapy at 23 months after the first visit. LGNECS is a newly proposed, extremely rare entity that has been reported under various names, including primary cutaneous carcinoid tumor. In the present case, this tumor shows a slow-growing nature and favorable prognosis, even though it harbors metastatic potential.

Upregulation of TGF-ß1 and basic FGF in elastofibroma: an immunohistochemical analysis.

Elastofibroma is a rare tumour that occurs in the subscapular space, and it typically presents in middle-aged and older individuals. The aetiology of elastofibroma remains unknown. Recent, sporadic reports have shown, immunohistologically, that fibroblasts in elastofibroma may produce abnormal elastic and collagen fibres through the action of transforming growth factor-beta (TGF-ß), a factor that promotes fibroblast proliferation. However, that finding lacked quantitative measurements and controls. Therefore, in this study, we performed quantitative, immunohistochemical analyses of TGF-ß1 and basic fibroblast growth factor (bFGF) in three elastofibromas, and we compared them to ten dermatofibromas and keloids, and five normal skin. In elastofibroma specimens, 16-59 % fibroblasts were positive for TGF-ß1 in the cytoplasm, compared to 96 % in dermatofibroma, 93 % in keloid and 2 % in normal dermis specimens. Also, in elastofibroma specimens, 26-67 % of fibroblasts were positive for bFGF in the cytoplasm, compared to 97 % in dermatofibroma, 97 % in keloid, and 22 % in normal dermis specimens. Intriguingly, the tumour size and growth rate were proportional to the percentage of cells positive for bFGF. Finally, greater levels of bFGF expressions in fibroblasts were associated with larger sized elastofibromas. These results suggested that elastofibroma development depended on high expression of TGF-ß1 and bFGF.