OBJECTIVES Melanocytic proliferations with Spitz differentiation present a difficult clinicopathologic dilemma, as their spectrum ranges from benign to malignant. Distinct entities include Spitz nevus, atypical Spitz nevus, and Spitzoid melanoma. Their histopathologic differentiation can be challenging, and cases of Spitzoid melanoma initially diagnosed as benign Spitz nevi are reported in the ...

The classification of benign sebaceous neoplasms has been challenged both by the assertion that sebaceous adenomas are really carcinomas and by difficulties in drawing the boundaries between sebaceomas and other lesions. We performed a clinicopathologic study of 30 cases of basaloid neoplasms with sebaceous differentiation, excluding cases of definite sebaceous carcinoma with severe nuclear aty...

Primary pancreatic lymphoma is a rare extranodal manifestation of any histopathologic subtype of B cell non-Hodgkin's lymphoma that predominantly involves the pancreas. It comprises less than 0.2% of pancreatic malignancies and less than 0.7% of non-Hodgkin's lymphomas. This lymphoma is almost never suspected clinically. It is usually diagnosed by surgical exploration for suspected adenoca...

background there is evidence of a possible etiological role of human papillomaviruses (hpvs) in the development of colorectal cancer. loss of p53 tumor suppressor gene function has been found in many malignancies and it can occur in a variety of ways, including gene mutation and interaction with the e6 protein of oncogenic hpvs. the objective of this study was to determine the prevalence of hpv...

CASE REPORT A 74-year-old male presented with an orbital tumor located in the left lacrimal fossa. Ocular examination showed hypotropia, exophthalmos and palpebral ptosis. DISCUSSION Removal of the tumor was performed by a lateral orbitotomy. The histopathologic study showed a tumor consistent with an adenocarcinoma of the lacrimal gland with apocrine differentiation.

major salivary gland tumors are uncommon and the exact nature of these tumors is not obvious. this study was carried out to compare the histological results of intraoperative frozen sections against those of permanent reports for major salivary glands masses. one hundred thirty-nine patients with major salivary gland masses who were candidates for surgery underwent an intraoperative frozen sect...

Histopathologic grading of astrocytic tumors based on current WHO criteria offers a valuable but simplified representation of oncologic reality and is often insufficient to predict clinical outcome. In this study, we report a new astrocytic tumor microarray gene expression data set (n = 65). We have used a simple artificial neural network algorithm to address grading of human astrocytic tumors,...

The role of the clinical laboratory in the diagnosis of abnormalities in gonadal development is reviewed, beginning with a description of the normal differentiation of the ovary and testis and the major types of disorders encountered. The conditions are classified as resulting from abnormal gonadal differentiation, defective endocrine function or excessive endocrine activity. Germ cell neoplasm...