Posterior cervical congenital dermal sinus tract: case report and review of literature.

BACKGROUND AND IMPORTANCE: Congenital dermal sinus tract (DST) is a rare spinal dysraphism characterized by a persistent tract lined by epithelial cells, beginning at the epidermis and terminating in deeper tissue layers. With 1% of all congenital DST cases found in the cervical region, only 4% of all cases are diagnosed after the age of 20. CLINICAL PRESENTATION: In this case, a 65-year-old woman with a congenital DST at the cervical level presented with symptoms of neck and some arm pain, suboccipital headaches, and unique external characteristics. Neck Disability Index and visual analog scale were used to assess the patient's preoperative and postoperative pain, and quality of life. Patient underwent an operative intervention, where the DST was surgically removed followed by interlaminar decompression at C1-C2, excision of the epidural component, and biopsy followed by plastic surgical repair. Pathology analysis indicated a squamous epithelial-lined sinus tract interacting with the dura. Most notably, a meningothelial proliferation with associated psammomatous calcifications was identified, similar to a meningioma. CONCLUSION: A review of literature was conducted to further discuss clinical and radiological presentation as well as to document the novel appearance of this congenital DST. As one of the oldest cases of DST, it demonstrated unusual pathological characteristics with a meningothelial proliferation, compatible with meningioma, reported at the epidural level.

Irradiated Skeletal Muscle Cells Mimicking Those of Atypical Fibroxanthoma on Mohs Frozen Sections.

ABSTRACT: Radiation can induce changes to skeletal muscle cells that may mimic and thus be confused with cells of atypical fibroxanthoma (AFX), pleomorphic dermal sarcoma, spindle cell squamous cell carcinoma, and other spindle soft-tissue tumors. An 80-year-old White man presented for Mohs micrographic surgery of an AFX on the left lateral neck. The medical history was notable for a tongue squamous cell carcinoma 9 years before that had been treated with wide local excision, left neck dissection, and radiation to the oral cavity and left neck. Frozen sections from the first stage of Mohs did not show typical AFX, but did reveal patchy clusters of atypical spindled and epithelioid cells, some with multiple nuclei. Because of the unusual appearance of these cells, Mohs micrographic surgery was halted, and the frozen tissue block was sent for permanent pathology examination. The cells on permanent sections stained positive for desmin, revealing them to be of skeletal muscle origin (in this case damaged platysma muscle because of late postradiation changes). It is thus important for the Mohs surgeon and the consultant dermatopathologist to be aware of the unusual histologic appearance of irradiated skeletal muscle to avoid confusion with other spindle cell tumors.

Fractal Deposits of a Hemostatic Hydrophilic Polymer in Mohs Micrographic Surgery Frozen Sections: A Histologic Analysis and Comparison With Sodium Polystyrene Sulfonate (Kayexalate).

Hydrophilic polymer with potassium ferrate (HPPF) powder is available as an over-the-counter hemostatic agent used by patients to stop superficial bleeding. In dermatology, it is applied to stop bleeding after superficial shave or punch biopsies or in open wounds after Mohs micrographic surgery. Despite its widespread availability, however, HPPF in histopathologic skin sections is highly unusual. We noted HPPF in skin closely resembles sodium polystyrene sulfonate (SPS) seen in colonic necrosis; SPS is a potassium binder given orally or rectally in hyperkalemic patients with end-stage renal disease. We describe the in vivo and in vitro histologic appearance of HPPF, compare HPPF with SPS, and discuss its potential migration into blood or lymph vessels.

Leukemia cutis coexisting with dermatofibroma as the initial presentation of B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma.

: Cutaneous involvement by chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is often observed in patients with a known history of systemic disease. Rarely, CLL/SLL may initially present with skin lesions. There are also rare reports of cutaneous CLL/SLL occurring in herpes scars and as an incidental finding in excision specimens for carcinoma. We present a 76-year-old woman with an inverted conical firm papule on the upper back that was clinically suggestive of a dermatofibroma. Excisional biopsy demonstrated the presence of a dermatofibroma coexisting with CLL/SLL. We describe the rare occurrence of CLL/SLL initially presenting as leukemia cutis. In addition, to the best of our knowledge, this is the first report of dermatofibroma coexisting with CLL/SLL. This finding further expands the types of skin lesions that may coincide with CLL/SLL.

Mitotic activity within dermal melanocytes of benign melanocytic nevi: a study of 100 cases with clinical follow-up.

It is generally accepted that otherwise benign intradermal or compound melanocytic nevi may show mitotic activity within dermal melanocytes. However, it is not known whether there is any clinical significance to this finding. Our objective is to analyze and describe the clinicopathologic features of benign nevi with mitotic activity (NMA). To do this, we collected 100 consecutive NMA during the usual course of business in our private dermatopathology practice. These cases were seen between the years 2000 and 2008. We then collected clinical and pathologic data on these cases and compared the findings with 100 control nevi without mitotic activity (CN). We compared these nevi with regard to demographic features, clinical history provided by clinician, and clinical follow-up, as well as anatomic site and season of biopsy, type of nevus, and selected histologic features (ie, trauma). We also estimate the incidence of NMA and describe the amount and location of mitotic figures within the NMA. Our results indicate that the incidence of NMA is 0.91%. Most (80) NMA revealed only one mitotic figure, whereas some (20) NMA revealed more than one mitotic figure. Most NMA (89) showed mitotic activity in the upper portion of the nevus, whereas some (11) showed mitotic activity in the lower portion of the nevus. NMA patients were of younger age than the CN patients (P = 0.0019). Compared with CN, the NMA were more likely to be from the extremities (P = 0.0113) or head and neck (P = 0.0237) and less likely to be from the trunk (P < 0.001). The NMA were also more likely to show histologic features suggesting a congenital onset (P < 0.001) and were more likely to be Spitz nevi (P = 0.0185). Compared with the CN, the NMA were more often reexcised (P = 0.0073) and more often, there was residual nevus in the reexcision specimen (P = 0.13), although the latter finding was not statistically significant. Anecdotally, 2 of our NMA were identified adjacent to invasive melanomas; however, on clinical follow-up, we were unable to detect any increased incidence of melanoma.