[Eccrine carcinoma: a diagnostic pitfall]. / Het eccrien carcinoom, een diagnostische valkuil.

BACKGROUND: The eccrine carcinoma is a rare form of skin adnexal malignancy, usually presenting as a locally invasive, solitary lesion in the head and neck region. Histopathologically and immunohistochemically, eccrine carcinomas are difficult to differentiate from cutaneous metastases of breast carcinomas. Unlike treatment of cutaneous metastasis, treatment of a solitary eccrine carcinoma entails excision, generally without systematic therapy. CASE DESCRIPTION: A seventy-year-old woman previously treated definitively for (in situ) breast cancer, undergoes excision of a nodule on the scalp. The histopathology report indicates a lesion typical for cutaneous metastasis of breast carcinoma. However, diagnostic imaging excludes recurrent breast cancer or metastatic spread. When subsequent clonality testing with archived breast cancer tissue from the earlier episode does not show a relation, the pathologist defines the lesion as an eccrine carcinoma. A re-excision is conducted, which does not show any residual tumorous tissue, and at follow-up there are no signs of recurrence or metastases. CONCLUSION: As a relatively rare and unknown malignancy, with strong histopathological resemblance to cutaneous metastasis of breast carcinoma, eccrine carcinoma poses a diagnostic challenge to both clinicians and pathologists.

Thermal artifacts in bladder tumors following loop endoresection: electrovaporization v electrocauterization.

BACKGROUND AND PURPOSE: Recently, the electrovaporization (EV) technique has been used for loop endoresection of bladder tumors. Our objective was to evaluate whether bladder tumors resected by EV with a loop wire are fit for histologic diagnosis. In addition, a quantitative comparison was made with the thermal artifacts created with a standard electrocautery (EC) loop resection. MATERIALS AND METHODS: In 26 patients with bladder tumors at various locations, endoresection was performed. In nonselective order, EV (N = 9; Gyrus device) or EC (N = 17; Valleylab device) was used. Histologic thermal artifacts were defined, and the diagnosis (pT classification) was determined. The linear depth of the thermal artifacts in the resected tissue was quantified with a computerized analysis system and statistically analyzed with the t-test. RESULTS: One case was excluded because the tissue was not fit for morphometric measurements. In all cases, a histologic diagnosis could be made. No qualitative differences were found between the groups in the extent of histologic thermal artifacts. The mean depth of the thermal artifact zone was 0.237 mm (range 0.060-0.469 mm; SD 0.098 mm) in the EV group and 0.260 mm (range 0.080-0.410 mm; SD 0.112 mm) in the EC group. This difference is not significant (P = 0.8). CONCLUSION: In these series, EV with a loop wire seemed to be a valid method to preserve bladder tumor specimens for histologic diagnosis. Compared with the EC method, there was no significant difference in the extent of thermal artifacts in the tissues resected.