Infections with multiple human papilloma virus (HPV) types have been reported, but their role in cervical carcinogenesis has not been fully elucidated. In this study, 236 cases with multiple HPV infection were examined and compared to 180 cases with single HPV infection. HPV genotyping was performed with cervico-vaginal swab specimens using multiplex (real-time) polymerase chain reaction (PCR). In multiple HPV infection, the most prevalent HPV genotype was HPV 53, followed by HPV 16, 58, 52, and 68. HPV 33, 35, 39, 51, 52, 53, 58, and 68 were high-risk-HPV (HR-HPV) genotypes that were more frequently detected in multiple HPV infection compared to that in single HPV infection. The association between multiple HPV infection and high-grade SIL (HSIL) was significantly stronger compared to that of single HPV infection and HSIL (p = 0.002). Patients with multiple HPV infection displayed persistent and longer duration of the HPV infection compared to patients with single HPV infection. Multiple HPV infections have distinct clinicopathologic characteristics. Since it is associated with persistent HPV infection, HSIL, and different HR-HPV strains in contrast to single HPV infection, the presence of multiple HPV infection should be reported; close follow up is warranted.

Despite advances in diagnostic imaging, surgical techniques, and systemic therapy, gastric cancer (GC) is the third leading cause of cancer-related death worldwide. Unfortunately, molecular heterogeneity and, consequently, acquired resistance in GC are the major causes of failure in the development of biomarker-guided targeted therapies. However, by showing promising survival benefits in some studies, the recent emergence of immunotherapy in GC has had a significant impact on treatment-selectable procedures. Immune checkpoint inhibitors (ICIs), widely indicated in the treatment of several malignancies, target inhibitory receptors on T lymphocytes, including the programmed cell death protein (PD-1)/programmed death-ligand 1 (PD-L1) axis and cytotoxic T-lymphocyte-associated protein 4 (CTLA4), and release effector T-cells from negative feedback signals. In this article, we review currently available predictive biomarkers (including PD-L1, microsatellite instability, Epstein–Barr virus, and tumor mutational burden) that affect the ICI treatment response, focusing on PD-L1 expression. We further briefly describe other potential biomarkers or mechanisms for predicting the response to ICIs in GC. This review may facilitate the expansion of the understanding of biomarkers for predicting the response to ICIs and help select the appropriate therapeutic approaches for patients with GC.

Background/Aim: Poorly differentiated thyroid carcinoma (PDTC), anaplastic thyroid carcinoma (ATC), and advanced DTC have poor outcomes. Materials and Methods: We performed next-generation sequencing in nine selected aggressive thyroid cancers. Results: Among the nine patients, the driver gene mutations BRAF V600E (3/9) and NRAS Q61K (1/9) were detected. Other oncogenic mutations included ERBB2 (1/9) and CDK4 (1/9). Telomerase reverse transcriptase (TERT) promoter mutation was found in five cases. Among tumor suppressor genes, mutations in TP53 (3/9), ARID1A (1/9), APC (1/9), MEN1 (1/9), DICER1 (1/9), and MED12 (1/9) were identified. RET fusions were found in two cases, one with PTDC and the other with ATC. The ATC with RET fusion also harbored TP53 and TERT promoter mutations. None of the PDTC cases had BRAF or RAS gene alterations. Conclusion: Since genetic alterations with therapeutic and prognostic implications were detected using next-generation sequencing, this technique is recommended to be performed for patients with aggressive thyroid cancer.

Background: We report a rare case of a metastatic neoplasm in the regional lymph nodes and peritoneum whose histopathologic and immunophenotypic profiles were most consistent with a diagnosis of medullary thyroid carcinoma (MTC), although a primary tumor was not histologically demonstrated in the thyroidectomy specimen. Case presentation: A 64-year-old man presented with abdominal pain and was found to have increased calcitonin level and a 20 mm lesion in the peritoneum. Peritoneum biopsy revealed plasmacytoid tumor cells which were positive for calcitonin and synaptophysin staining. The patient had a past history of neck dissection due to left side neck mass. The histology revealed metastatic carcinoma with a nested pattern surrounded by fibrous stroma with stromal amyloid deposition. With immunohistochemistry, the findings were most consistent with metastatic MTC, but following total thyroidectomy showed no malignancy. Next-generation sequencing identified a pathogenic HRAS mutation, but RET mutation was not identified. Despite vandetanib treatment, the disease progressed and the patient expired. Conclusions: This case highlights a rare presentation of a metastatic neoplasm highly suggestive of RET wild-type MTC with peritoneal involvement, despite the absence of an identifiable primary lesion.