Cytology of primary cutaneous Langerhans cell histiocytosis with a malignant phenotype. A case report.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a proliferative disorder of Langerhans cells, but the nature of LCH, whether reactive, benign, or malignant and neoplastic, is controversial. We encountered a case of LCH showing a malignant phenotype initially localized in the skin of an elderly woman. Since there is no other report on the cytologic appearance of primary cutaneous LCH or on LCH with a malignant phenotype, we compared the cytologic features of this case with those of benign cases at other sites reported in the literature. CASE: A 74-year-old woman presented with a gradually enlarging and partially ulcerated skin lesion expanding both sides of her right hand. On histologic and ultrastructural analyses of surgically resected tissue, we diagnosed the lesion as Langerhans cell histiocytosis originating in the skin. Although the patient had no recurrence or metastases for six months after surgical resection of the primary skin lesion and radiation therapy, the tumor extended multisystemically, and the patient died of multiple organ failure 14 months after the initial diagnosis. CONCLUSION: Imprint and scrape cytology of multiple skin lesions six months after surgery was useful in immediately diagnosing the recurrent LCH. The tumor cells had indented, twisted or grooved nuclei, and some had intranuclear inclusions. Immunocytochemically the cells were positive for CD1a and S-100 protein. Numerous eosinophils were seen in the background.

Diagnostic utility of galectin-3 and CD26/DPPIV as preoperative diagnostic markers for thyroid nodules.

The aim of this study was to search for diagnostic markers that could correctly identify thyroid nodular lesions requiring urgent surgical treatment. We investigated whether galectin-3 and dipeptidyl peptidase IV (CD26/DPPIV) could be potential markers for improving the diagnostic accuracy of conventional cytology. Seventy-nine patients with histologically proven thyroid diseases were analyzed. The immunocytochemical staining results showed galectin-3 expression in neoplastic cells of all 37 papillary carcinomas, five of six follicular carcinomas, all three anaplastic carcinomas, one of three medullary carcinomas, and two of 14 follicular adenomas. All 16 adenomatous goiters were negative for galectin-3 immunostaining. On the other hand, all 37 papillary carcinomas, all six follicular carcinomas, and one of three anaplastic carcinomas revealed CD26/DPPIV expression, whereas all three medullary carcinomas were negative. Among benign thyroid lesions, four of 14 follicular adenomas and two of 16 adenomatous goiters exhibited varying degrees of immunoreactivity for CD26/DPPIV. RT-PCR analysis demonstrated overexpression of galectin-3 and CD26/DPPIV mRNAs in all six papillary and all three follicular carcinomas analyzed, whereas the mRNA expressions of these molecules were barely or not detectable in benign thyroid lesions and normal thyroid tissues, except for one case of follicular adenoma. In conclusion, we demonstrate that galectin-3 and CD26/DPPIV were consistently coexpressed at protein and mRNA levels in differentiated thyroid carcinomas. We propose that combined immunostaining for galectin-3 and CD26/DPPIV in the preoperative evaluation of thyroid nodules may play a role in accurate cytodiagnosis.