Enhanced Angiogenesis in Salivary Duct Carcinoma Ex-Pleomorphic Adenoma.

Salivary duct carcinoma (SDC) is morphologically similar to breast cancer, with HER2-overexpression reported. With regard to the pattern of disease onset, SDC can arise from de novo or carcinoma ex-pleomorphic adenoma (Ca-ex-PA). Recently, multiple molecular profiles of SDC as well as breast cancer have been reported, with significant differences in HER2 expression between Ca-ex-PA and de novo. We assessed the differences in gene expression between onset classifications. We conducted immunohistochemical analysis and HER2-DISH for 23 patients and classified SDCs into three subtypes as follows: "HER2-positive" (HER2+/any AR), "Luminal-AR" (HER2-/AR+), and "Basal-like" (HER2-/AR-). We assessed the expression levels of 84 functional genes for 19 patients by using a qRT-PCR array. Ten cases were classified as HER2-positive, seven cases as Luminal-AR, and six cases as Basal-like. The gene expression pattern was generally consistent with the corresponding immunostaining classification. The expression levels of VEGFA, ERBB2(HER2), IGF1R, RB1, and XBP1 were higher, while those of SLIT2 and PTEN were lower in Ca-ex-PA than in de novo. The functions of those genes were concentrated in angiogenesis and AKT/PI3K signaling pathway (Fisher's test: p-value = 0.025 and 0.004, respectively). Multiple machine learning methods, OPLS-DA, LASSO, and RandomForest, also show that VEGFA can be a candidate for the characteristic differences between Ca-ex-PA and de novo. In conclusion, the AKT/PI3K signaling pathway leading to angiogenesis was hyper-activated in all SDCs, particularly in those classified into the Ca-ex-PAs. VEGFA was over-expressed significantly in the Ca-ex-PA, which can be a crucial factor in the malignant conversion to SDC.

Genetic mutation analysis of the malignant transformation of sinonasal inverted papilloma by targeted amplicon sequencing.

BACKGROUND: The mechanism underlying the malignant transformation of inverted papilloma (IP) has not yet been elucidated. METHODS: To clarify the genes responsible for the malignant transformation, we analyzed 10 cases of IP, 8 of IP with dysplasia, and 11 of squamous cell carcinoma (SCC) by targeted amplicon sequencing. RESULTS: The number of mutant genes increased in the order of IP < dysplasia < SCC. Significant differences were observed in the mutation rates of three genes (KRAS, APC and STK11) in particular. TP53 was altered frequently in each group and might be involved in malignant transformation based on to the site of the mutation. A comparison of the genetic variants by region of IP tissue among patients with IP alone, and those with dysplasia or SCC revealed significant differences in the mutation rate of the KRAS gene. CONCLUSION: Identification of genetic mutations in KRAS is effective for predicting the malignant transformation of IP.

Validation of the 8th edition of the AJCC/UICC TNM staging system for tongue squamous cell carcinoma.

BACKGROUND: The revised 8th edition of the AJCC/UICC staging system was released in January 2017, and depth of invasion (DOI) was added to the new criteria for T classification in oral cavity cancer. In this study, we evaluated whether the 8th edition presents the prognosis and risk of nodal metastasis in patients with squamous cell carcinoma of tongue more accurately than did the 7th edition. METHODS: The data for 112 patients were obtained and reclassified based on the criteria presented in the 8th edition. RESULTS: Seven patients previously staged as T1 based on the criteria in the 7th edition were reclassified as T2 based on the 8th edition, while 19 T2 patients were reclassified as T3, and 9 T4a patients were reclassified as T3. T3 in the 8th edition represents a homogenous population showing the same prognosis, while T2 in the 8th edition represents a heterogenous population. Nodal metastasis was significantly correlated with T classification in both editions and DOI. However, neither the T classification in the 7th or 8th edition, nor DOI could predict the probability of potential nodal metastasis in patients with cN0 disease. CONCLUSIONS: The classification on T3 in the 8th edition can be seen as reasonable with regard to prognosis. Nodal metastasis was significantly correlated with T classification and DOI; however, the probability of subsequent nodal metastasis in patients with T2N0 was almost same for the criteria in the 7th and 8th editions, therefore, the same careful management as before is required for patients with N0 disease.

Expression of p53, p16, cyclin D1, epidermal growth factor receptor and Notch1 in patients with temporal bone squamous cell carcinoma.

BACKGROUND: The aim of this study was to investigate the expression of p53, p16, cyclin D1, epidermal growth factor receptor (EGFR) and Notch1 in temporal bone squamous cell carcinoma (TBSCC) tissue samples by immunohistochemistry (IHC), and to evaluate the association between these biomarkers and clinicopathological features. METHODS: We performed a retrospective, single-institution review of 30 TBSCC patients treated with curative intent between April 2006 and March 2015. All tissue samples were obtained from pretreatment biopsy specimens or surgical specimens and using IHC staining. RESULTS: Ten patients were categorized as T1, seven as T2, five as T3 and eight as T4. Nine patients had clinically positive lymph node metastasis. The positive expression of p53 and EGFR was significantly associated with T classification (P = 0.042 and P = 0.0039). EGFR expression was significantly more frequent in patients with positive lymph node metastasis compared with patients without node involvement (P = 0.017). In the analysis of the association between protein expression by IHC staining and prognosis, the positive expression of EGFR and Notch1 was significantly correlated with poor survival outcomes in TBSCC (P = 0.015 and P = 0.025) CONCLUSION: Overexpression of p53 and EGFR may be valuable biomarkers for identifying individuals at high risk of developing tumors in TBSCC. Furthermore, the positive expression of EGFR was significantly associated with poor survival outcome. Anti-EGFR therapy has potential for use as the treatment modality of choice for advanced-stage TBSCC as well as other head and neck squamous cell carcinomas.