Novel genomic alteration in superficial esophageal squamous cell neoplasms in non-smoker non-drinker females

Alcohol consumption and smoking pose a significant risk for esophageal squamous cell neoplasia (ESCN) development in males; however, ESCN is often diagnosed in non-drinking and non-smoking females. The mechanisms underlying these differences remain elusive, and understanding them can potentially identify novel pathways involved in ESCN development. We performed short-read sequencing to identify somatic variants on a cancer panel targeting 409 genes using DNA extracted from the superficial squamous cell carcinoma (ESCC) tissues and adjacent non-neoplastic epithelium (NE), and immunohistochemical staining of the protein encoded by the target gene. All male patients (n = 117) were drinkers or smokers, whereas 45% of the female patients (n = 33) were not. Somatic variants were compared among three age-matched groups: 13 female ESCC patients with smoking and drinking habits (known-risk group, F-KR), 13 female ESCC patients without these habits (unknown-risk group, F-UR), and 27 males with ESCC and smoking and drinking habits (M-KR). In the NE, the frequencies of CDKN2A variants were significantly higher in F-UR than in F-KR and M-KR. In both ESCC and NE, p14ARF was significantly overexpressed in F-UR than in the other groups. In conclusion, CDKN2A might be important in ESCC development, independent of known risk factors.

Characteristics of non-neoplastic epithelium that appears within gastric cancer with and without Helicobacter pylori eradication: A retrospective study

A non-neoplastic epithelium (NE) often appears in gastric cancer (GC). We explored the histological features of NE in comparison between HP-eradicated and HP-infected GCs. We enrolled 40 HP-eradicated and 40 HP-infected GCs matched by size, macroscopic and histological type. NE was classified into full gland type and surface type; the former was a non-neoplastic gland isolated within cancer, and the latter was NE on the surface of the cancer. Surface type was additionally divided into NE at the cancer margin (marginal surface type) and NE inside cancer (internal surface type). The primary endpoints were the frequency and the length ratio (the ratio to cancer length) of NE. The secondary endpoints were the relationships between NE and clinicopathological factors, including endoscopic findings of a gastritis-like appearance (GLA), reddish depressed lesion (RDL), and white nodular mucosa (WNM). The frequency and length ratio of the internal surface type in HP-eradicated GCs were significantly higher (82.5% vs 50%, P = 0.005) and larger (11.6 ± 10.6 vs 4.2 ± 9.9, P < 0.001) than those in HP-infected GCs, and the increase was more significant according to the passage of time since HP eradication. The frequency and length ratio of marginal surface type and full gland type were not significantly different between the two groups, but the coexistence of internal surface and full gland types was statistically significant (p < 0.001). The frequencies of GLA, RDLs, and WNM in HP-eradicated GCs were significantly higher than those in HP-infected GCs. GLA-positive GCs were covered more widely by internal surface type than GLA-negative GCs (13.3% vs. 6.6%, P = 0.003). Various types of NE were noted in gastric cancer, and the internal surface type of NE was shown to be significantly linked to HP-eradicated cancer and GLA.

METAPLASTIC CARCINOMA OF BREAST

Metaplastic carcinoma of the breast is a rare but aggressive type of breast cancer that has been recognized as a unique pathologic entity by the World Health Organization. Morphologically, it is characterized by the differentiation of neoplastic epithelium into squamous cells and/or mesenchymal-looking elements (spindle cells, cartilage or bone, etc). It shares many similarities with invasive ductal carcinoma and benign lesions on mammography, which further complicates the diagnosis. Treatment for metaplastic breast carcinoma is relatively unknown because of the rarity of the disease, but studies suggest that removal of the tumor and adjuvant radiation therapy has the greatest benefit.

Metaplastic Carcinoma of the Breast with Squamous Differentiation: A Case Report from the University Teaching Hospital of Kigali (CHUK), Rwanda

Metaplastic breast carcinoma is a rare and aggressive condition, accounting less than 1% of breast malignancies. It presents with large mass and frequently with distant metastasis at time of diagnosis. Morphologically, it is characterized by the differentiation of neoplastic epithelium into epithelial or mesenchymal-looking elements like squamous cells, spindle cells, cartilage, or bone and has poor prognosis with its triple negative status.

Basal Cell Carcinoma Arising within a Trichoepithelioma: An Immunohistochemical Study

Background: Trichoepithelioma (TE) and basal cell carcinoma (BCC) of skin represent distinct tumor entities but they have a close histogenetic and phenotypic relationship.Objective: A unique case of a BCC arising within a TE is described with an emphasis on the analysis of different and for each tumor type typical immunophenotype.Material and Methods: A 71-year-old man presented with a subcutaneous solid tumor in the lumbar region. The resected tumor specimen was studied by immunohistochemistry.Results: Histology revealed a coexistence of classic TE and nodular BCC. Both tumors were strongly positive for BerEP4 and negative for EMA. Neoplastic epithelium of the BCC showed a diffuse staining for Bcl-2, while the TE expressed Bcl-2 almost exclusively in the peripheral cells of tumor islands. In the BCC, neoplastic nodules exhibited a focal staining for CD10, while the peritumorous stroma did not. In contrast, the TE showed a focal immunoreactivity for CD10 in the stromal cells around the neoplastic islands which were completely negative. The TE contained intratumorous CK20-labeled Merkel cells but they were not detected in the BCC. A stromal immunore-activity for CD34 was found in both tumors. Proliferative activity (Ki-67) was slightly higher in the BCC than in the TE.Conclusion: Although a concomitant presence of TE and BCC in the same skin lesion is a unique finding, it may be sometimes encountered in a biopsy practice. Pathologists should provide a careful histologic examination of the whole TE lesion with precise section sampling to unveil such possible association.

PS02.025: CHARACTERISTICS OF SUPERFICIAL BASALOID SQUAMOUS CELL CARCINOMA TREATED BY ENDOSCOPIC RESECTION

Background Basaloid squamous cell carcinoma (BSCC) is a rare esophageal carcinoma. And the characteristics especially in early stage is unknown. Methods The aim of this study is to clarify the characteristics of superficial BSCC. Thirteen patients (9 males and 4 females) with BSCC treated by endoscopic resection (12 ESD and 1 EMRC) from January 2000 to March 2017 were enrolled in this retrospective study. The median age was 67 (57–83). The median follow-up period was 24 (12–115) months. T1a-EP/LPM and T1a-MM/T1b-SM1 without lymph duct invasion (LDI) was followed up. T1a-MM/T1b-SM1 with LDI or T1b-SM2 were treated by additional treatment (AT). Results 1. En-bloc resection and R0 resection rate was 100% and 100%, respectively. 2. Macroscopic type; 0-IIa, 0-IIb and 0-IIc was 4, 1 and 8, respectively. 3. The median tumor diameter was 27 (2–62) mm. 4. Invasion depth; T1a-LPM, T1a-MM/T1b-SM1, and T1b-SM2 was 3, 5 and 5, respectively. 5. Histological characteristics; All BSCC were covered by SCC or non-neoplastic squamous epithelium. 6. Endoscopic characteristics; SMT like appearance was found in 46% (6/13). Yellowish nodules were observed in 23% (3/13). This finding was observed, when BSCC exist superficial epithelial layer covered by thin non-neoplastic epithelium. 7. Prognosis A: T1a-LPM (N = 3). Two patients are alive without recurrence, and 1 patient died of other disease. B: T1a-MM/SM1 (N = 5). Two of 3 patients without LDI were followed up and alive. Remaining one patient wanted to be treated by CRT, and alive. Two patients had LVI, however they were followed up without AT because of patient's hope. One is alive, and another died of other disease. C: T1b-SM2 (N = 5). Two and one patients were treated by surgery and chemotherapy, respectively, and alive without recurrence. Remaining two patients were followed up without AT. One of 2 patients are alive without recurrence. Another patient dead of other disease. Conclusion 1. All of BSCC were covered by SCC or non-neoplastic epithelium. 2. SMT like appearance and yellowish nodules under squamous cell epithelium were the characteristic endoscopic findings. 3. 40% of T1aMM/T1bSM1 had LDI. It's higher than that of SCC. Therefore, En-bloc resection is necessary for the detailed histological examination. Disclosure All authors have declared no conflicts of interest.

Sebaceous cell differentiation in a canine oral papilloma

Papillomas caused by viral infection are well-known tumors in animals. Microscopic features typically include neoplastic epithelium with hyperkeratosis and koilocytes. An 8-y-old castrated male Shih Tzu dog was presented with a small exophytic mass on the external upper lip. The mass was diagnosed as a viral papilloma based on microscopic and immunohistochemical examination. Sebaceous cell differentiation was found in the neoplastic epithelium of the tumor, which is a rare finding in humans or animals.