Mapping biopsy with punch biopsies to determine surgical margin in extramammary Paget's disease.

It is difficult to determine the appropriate resection margin of extramammary Paget's disease (EMPD). A high recurrence rate is reported in spite of using Mohs micrographic surgery (MMS), which is performed commonly. Preoperative mapping biopsy is easier to perform than MMS. In Japan, the following method is recommended instead of MMS: well-defined border and margins histologically confirmed by mapping biopsy should be resected with 1-cm margin and ill-defined border with 3-cm margin. This study aimed to evaluate the accuracy of the Japanese guideline and to assess our mapping biopsy method compared with MMS. Preoperative mapping biopsy specimens were obtained beyond the clinical border for at least four directions in each patient. To confirm the presence of residual Paget's cells postoperatively, narrow specimens were obtained along the surgical margin. Retrospective evaluation of 17 EMPD patients was conducted concerning histological spread of Paget's cells and recurrence ratio. There were 86 directions showing a well-defined border, and in 9.3% (8/86), Paget's cells were still observed at 1-cm resection line. On the other hand, there were 21 directions showing an ill-defined border, and unnecessary radical resection was performed in 90% (19/21) of directions with 3-cm resection line. Although postoperative histological examination showed residual Paget's cells in 47% (8/17) of patients and additional resections were not performed, recurrence rate was only 5.9% (1/17). The resection line of EMPD should be based not on clinical features, but on mapping biopsy. Mapping biopsy is equivalent to MMS concerning recurrence rate and, though conventional, is useful method to treat EMPD.

Erosive pustular dermatosis of the scalp-like eruption due to gefitinib: case report and review of the literature of alopecia associated with EGFR inhibitors.

A 69-year-old Japanese woman with multiple brain metastases secondary to non-small-cell lung cancer was treated with radiosurgery, and subsequently started oral gefitinib. Three years later, she presented with erythematous erosive alopecia with pustules on the scalp. A biopsy specimen showed a dense perifollicular infiltration composed of lymphocytes, neutrophils and abundant plasma cells. Methicillin-resistant Staphylococcus aureus was cultured from the lesions; however, treatment with antibiotics was not effective. We diagnosed an eruption resembling erosive pustular dermatosis of the scalp. Although oral steroids did not improve the lesions, the pustules and erythema of the scalp rapidly improved within a few weeks after discontinuation of gefitinib. There have been only 11 case reports of alopecia associated with epidermal growth factor receptor (EGFR) inhibitors including our case. It is noteworthy that all cases were female, and most cases involved the parietal scalp. Moreover, the reduction or discontinuation of the EGFR inhibitors was needed in all cases with erythematous alopecia, which remained as scarring alopecia.

Case of muscle abscess due to disseminated nocardiosis in a patient with autoimmune hemolytic anemia, and review of the published work.

Although disseminated nocardiosis has been increasing with the expansion of immunosuppressive therapy and improvement in diagnostic methods, muscle abscess is a rare complication. There have been only nine case reports of muscle abscess due to Nocardia infection in the English-language published work. We present a case of muscle abscess with disseminated nocardiosis, and review the published work. The patient had been taking prednisolone at 20 mg a day for autoimmune hemolytic anemia for 14 years. She presented with erythema on her thigh resembling cellulitis. Computed tomography showed muscle abscess. The isolated organism was identified as Nocardia farcinica employing polymerase chain reaction and antibiotic sensitivity testing. The diagnosis of muscle abscess due to nocardiosis can be easily missed because there are no characteristic symptoms.

Hyperkeratotic variant of porokeratosis Mibelli with dermal amyloid deposits.

We report a case of hyperkeratotic variant of porokeratosis Mibelli with dermal amyloid deposits. A 66-year-old man presented with multiple brownish keratotic lesions on the lower extremities, a verrucous nodule on the third toe of the left foot and brownish verrucous plaques on the buttocks for several years. Histopathological examination of the hyperkeratotic plaque in the right gluteal region revealed extreme hyperkeratosis and cornoid lamella. In the papillary dermis, there were prominent eosinophilic amorphous materials which were positive to Dylon staining. Treatment with oral etretinate resulted in a remission of the skin lesions in this case.

Fluid-fluid level in a giant epidermal cyst of the buttock.

We describe a case of a giant epidermal cyst of the buttock that demonstrated a fluid-fluid level on imaging. There have been no previously reported cases of epidermal cysts containing a fluid-fluid level, so our case was considered to be very exceptional. A 39-year-old man had had a slowly enlarging giant subcutaneous mass in the left buttock for more than 10 years. It was elastic-soft, well-circumscribed and smooth-surfaced. Ultrasonography showed a well-circumscribed hypoechoic mass with a fluid-fluid level in the subcutis of the left buttock. Magnetic resonance imaging (MRI) showed a well-circumscribed cystic mass measuring 8 cm x 5.5 cm x 5.5 cm in the same place that the ultrasonography indicated. It was hypointense on the T1-weighted image, hyperintense on the T2-weighted image, and contained a fluid-fluid level on both the T1- and T2-weighted images. It bordered on the anus, but neither adhered nor formed a fistula with it. A surgical excision was performed. The mass was diagnosed histopathologically as an epidermal cyst. The occurrence of fluid-fluid levels in epidermal cysts should be kept in mind in the differential diagnosis of subcutaneous soft tissue tumors.

Subungual glomus tumor diagnosis based on imaging.

A 50-year-old woman had had tenderness of the nail bed of the right thumb for more than 20 years. For the previous 5 or 6 years, she had also had attacks of pain with exposure to cold, and deformity of the right thumb nail plate began to appear. There was red discoloration on the proximal aspect of the nail bed, and a longitudinal fissure on the distal aspect of the nail plate. Ultrasonography showed a well-circumscribed hypoechoic area under the proximal aspect of the nail plate and the nail matrix. Color Doppler ultrasonography showed subtle flow signals within the hypoechoic area. Magnetic resonance imaging showed a well-circumscribed mass in the same place that the ultrasonography indicated. It was isointense to the dermis of the nail bed on the T1-weighted image and hyperintense on the T2-weighted image. Radiography showed subtle dorsal bone erosion in the distal phalanx. Surgery was performed. Histologically, the diagnosis of a subungual glomus tumor was made. We diagnosed the exact location and size of the subungual glomus tumor by preoperative imaging and completely removed it easily and safely. Imaging is very useful for diagnosing tumors of the nail unit.