Small Cell Carcinoma of the Cervix in Liquid-Based Pap Test: Utilization of Split-Sample Immunocytochemical and Molecular Analysis

Small cell (neuroendocrine) carcinoma of the uterine cervix (SMCC) is a rare, highly aggressive malignant neoplasm. Both conventional and liquid-based cytology (LBC) cervical smears have low sensitivity in diagnosing SMCC, requiring immunocytochemical (ICH) confirmation. We present the first series of SMCC primarily diagnosed in cytology specimens, and ICH studies performed on the residual LBC specimens with subsequent confirmation of the diagnosis on surgical pathology specimens. Immunocytochemical stains for keratin, p16INK4, and neuroendocrine markers (synaptophysin, chromogranin, CD56) were performed on additional ThinPrep slides. HPV test used chromogenic in situ hybridization high risk HPV DNA probe. The Pap smears in all three specimens were highly cellular with a mixture of squamous cells and numerous well-preserved single or small cohesive clusters of malignant epithelial cells. Tumor cells were small, monomorphic with minimal cytoplasm and high nuclear/cytoplasmic ratio. There was significant nuclear overlap, but no nuclear molding, or smudging of nuclear chromatin. The chromatin pattern was stippled. A background tumor diathesis was prominent. Atypical squamous cells of undetermined significance (ASCUS) were noted in one case, and markedly abnormal squamous cells were seen in another case. The main cytology differential diagnoses included high-grade squamous intraepithelial lesion and an endometrial adenocarcinoma. Immunocytochemical positivity for the neuroendocrine markers supported the diagnoses of SMCC in all three cases. The morphologic features of the concurrent surgical pathology specimens were typical of SMCC. The tissue diagnoses were also confirmed by immunohistochemistry. Our study allows us to conclude that SMCC can be primarily diagnosed in LBC specimens using a panel of immunocytochemical stains

Lymphatic Vessel Density Is Significantly Increased in Melanoma

Backgrounds: Melanoma is well known for its ability to involve regional lymph nodes in the early stage. However, the presence of lymphangiogenesis in melanoma is still controversial due to lack of lymphatic-specific markers. The purpose of this study was to determine the intra- and peritumoral lymphatic vessel density (LVD) using a novel lymphatic vessel-specific marker D2-40 and compare it to general vessel density (GVD) as determined by CD31 immunostaining in a series of melanocytic lesions. Methods: The intra- and peritumoral GVD and LVD were examined by immunohistochemistry using D2-40 and CD31 antibodies in a series of melanocytic lesions. Results: We found significantly higher intratumoral LVD in melanomas as compared to either common acquired or dysplastic nevi (p \u3c 0.01). Although peritumoral LVD in melanoma and malignant melanoma in situ was higher compared to nevi, the difference did not reach statistical significance (p = 0.059). There was no significant difference in GVD among the various groups of melanocytic lesions. Conclusions: Our results show that intratumoral LVD is significantly increased in melanomas compared to benign nevi. The higher intratumoral lymphatic density in invasive melanomas suggests that melanoma cells might promote lymphangiogenesis. In addition, assessment of intratumoral LVD may be potentially useful in the differential diagnosis of melanocytic lesions

Diagnostic Utility of Mucin Profile in Fine-Needle Aspiration Specimens of the Pancreas: An Immunohistochemical Study With Surgical Pathology Correlation

BACKGROUND. The cytologic differentiation between neoplastic and reactive/reparative processes in the endoscopic ultrasound-guided fine-needle aspirations (EUS-FNA) of the pancreas can be difficult. Malignant transformation of the pancreatic ductal epithelium changes the expression of apomucins. The goal of the current study was to determine an optimal immunohistochemical panel of mucin (MUC) antibodies that would allow the cytomorphologic distinction of pancreatic ductal adenocarcinoma and its differentiation from reactive/reparative processes and inadvertently sampled gastric and duodenal mucosa. METHODS. Pancreatic EUS-FNA specimens performed on 351 patients were reviewed. Expression profiles of MUC1, 2, 5AC, and 6 were examined on 56 cell block sections and 26 follow-up pancreatectomy specimens. RESULTS. MUC1 and 6 expression was found in nonneoplastic pancreatic samples, whereas there was an absence of expression of MUC2 and 5AC. MUC2 was detected in mucosal goblets cells of the duodenum, MUC6 in Brunner glands, and MUC5AC in gastric foveolar cells. MUC5AC expression in differentiating ductal adenocarcinomas from benign conditions demonstrated better operating characteristics than either MUC1 or MUC6. The apomucin expression pattern both in cytology and follow-up surgical pathology specimens was similar. In surgical pathology specimens, the panel of 3 antibodies, MUC1+/MUC2-/MUC5AC+, was noted in 15 of 17 ductal carcinomas (88.2%). In nonneoplastic pancreatic tissue, the expression panel MUC1+/MUC2-/MUC5AC- was observed in 14 of 17 (82.4%) cases. In cytology specimens, the combination of MUC1+/MUC2-/MUC5AC+ was noted in 21 of 30 ductal carcinoma cases (70.0%), 3 of 6 atypical cases (50%), and 1 of 1 suspicious for malignancy cases (100%). The combination MUC1+/MUC2-/MUC5AC+ was not observed in any of the negative for malignancy or reactive cases (0 of 6). CONCLUSIONS. The most optimal panel for the diagnosis of ductal adenocarcinoma in both the EUS-FNA specimens is a panel including MUC1/MUC2/MUC5AC, whereas a panel of all 4 antibodies (MUC1, 2, 5AC, and 6) will in addition aid in differentiating inadvertently sampled normal/reactive duodenal and gastric epithelium from neoplastic pancreatic tissue