Multivariate analysis of breast tissue using optical parameters extracted from a combined time-resolved fluorescence and diffuse reflectance system for tumor margin detection.

Significance: Breast conservation therapy is the preferred technique for treating primary breast cancers. However, breast tumor margins are hard to determine as tumor borders are often ill-defined. As such, there exists a need for a clinically compatible tumor margin detection system. Aim: A combined time-resolved fluorescence and diffuse reflectance (TRF-DR) system has been developed to determine the optical properties of breast tissue. This study aims to improve tissue classification to aid in surgical decision making. Approach: Normal and tumor breast tissue were collected from 80 patients with invasive ductal carcinoma and measured in the optical system. Optical parameters were extracted, and the tissue underwent histopathological examination. In total, 761 adipose, 77 fibroglandular, and 347 tumor spectra were analyzed. Principal component analysis and decision tree modeling were performed using only TRF optical parameters, only DR optical parameters, and using the combined datasets. Results: The classification modeling using TRF data alone resulted in a tumor margin detection sensitivity of 72.3% and specificity of 88.3%. Prediction modeling using DR data alone resulted in greater sensitivity and specificity of 80.4% and 94.0%, respectively. Combining both datasets resulted in the improved sensitivity and specificity of 85.6% and 95.3%, respectively. While both sensitivity and specificity improved with the combined modeling, further study of fibroglandular tissue could result in improved classification. Conclusion: The combined TRF-DR system showed greater tissue classification capability than either technique alone. Further work studying more fibroglandular tissue and tissue of mixed composition would develop this system for intraoperative use for tumor margin detection.

Endocrine Mucin-Producing Sweat Gland Carcinoma, a Histological Challenge.

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a rare adnexal tumor of the skin with low-grade cytological features and neuroendocrine differentiation. It has a predilection for the skin of the eyelid, but has also been reported in the face and rarely extra-facial locations. The tumor is seen more frequently in women and on average affects the elderly. It is histologically and immunohistochemically analogous to solid papillary carcinoma of the breast/endocrine ductal carcinoma in situ with a nodular, solid, papillary, and/or cribriforming architecture, neuroendocrine differentiation, and mucin production. Since it was first described by Flieder et al. in 1997, less than 60 cases have been reported in literature. We describe the morphological and immunohistochemical features of another case with a review of the common histological differential diagnoses and emphasize the salient features that help distinguish this rare neoplasm.

A Case of Patch Stage of Kaposi's Sarcoma and Discussion of the Differential Diagnosis.

A 55 year old HIV positive male had a skin lesion biopsy which showed atypical vascular proliferation within the superficial and deep dermis with mild atypia of lining endothelial cells. A sparse lymphoplasmacytic infiltrate surrounding the irregular vascular channels was noted. Immunohistochemistry highlighted the atypical blood vessels with the vascular markers CD31, CD34 and Factor VIII. The differential diagnosis included unusual vascular or lymphatic proliferations, stasis dermatitis, kaposiform hemangioendothelioma, progressive lymphangioma and angiosarcoma with focal Kaposi's sarcoma features. Characteristic human herpes virus-8 positive staining helped support the diagnosis of patch stage of Kaposi's sarcoma. Herein, we discuss the case findings, differential diagnosis and characteristic histological findings associated with the patch stage of Kaposi's sarcoma which can be an elusive diagnosis.