Recurrent atypical fibroxanthoma with satellite metastasis.

Atypical fibroxanthoma (AFX) is a cutaneous neoplasm of uncertain etiology that develops on sun-exposed regions of elderly males. It is widely considered to act indolently, despite its highly malignant cytologic features. Reports of metastatic AFX are very rare, and recurrence is uncommon. We report a case of recurrent AFX exhibiting a pattern of satellite metastasis followed by evidence of regional lymph node metastasis. A 76-year-old male with prior occupational and therapeutic radiation exposure and numerous squamous cell carcinomas had AFX of the left vertex scalp limited to the dermis completely removed by micrographic surgery. Twenty months later, multiple lesions appeared at the site of previous surgery. Imaging revealed no metastases or calvarial involvement. Wide local excision showed multiple well-defined nodules involving dermis and subcutis. The primary and recurrent neoplasms were similar and composed of pleomorphic epithelioid and spindled cells with marked nuclear atypia, hyperchromasia and mitotic activity. Immunohistochemistry was positive for CD10, procollagen1 and vimentin and negative for cytokeratins AE1/AE3, cytokeratins 5/6, 34ßE12, MNF116, p63 CD31, Mart1, smooth muscle actin, desmin, S100 and CD34. Forty-eight months after removal of the primary, left intraparotid and posterior triangle lymph nodes are suspected to be involved by metastasis using clinical and positron emission tomography/ computed tomography examinations.

Intraoperative imprint cytology for evaluation of sentinel lymph nodes from Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous malignancy. Intraoperative imprint cytology (IIC) can potentially avoid second operations for completion lymphadenectomy when nodal metastases are found during nodal staging with sentinel lymph node biopsy (SLN). This represents the first series of IIC for MCC we are aware of and our initial experience. Patients with biopsy-proven MCC underwent SLN (at the time of wide excision) using a double indicator technique with 99technetium sulfur colloid and isosulfan blue. SLN were identified and bisected and touch imprints of each half were made. One half was air-dried and stained with Diff-Quick and the other was fixed with 95 per cent alcohol and stained with hematoxylin and eosin (H&E). Paraffin-embedded sections were examined by H&E. Eighteen patients underwent successful SLN mapping procedures. IIC was negative in 84.2 per cent (16) cases. Three false-negatives occurred with IIC, but there were no false-positives, making the sensitivity 33 per cent and the specificity 100 per cent. Two of four patients with positive pathology-confirmed SLN also had positive IIC. SLN mapping has usefulness in patients with MCC. IIC is feasible and accurate in evaluating the SLN. IIC is a practical diagnostic tool when intraoperative analysis of SLN biopsy is desired for MCC.