An evolving presentation of cutaneous tuberculosis.

Tuberculosis is a fairly common disease in the United States and around the world, newly infecting ten million people throughout the world per year. Despite the pervasiveness of tuberculosis, cutaneous tuberculosis (CTB) rarely manifests worldwide. Tuberculous infections of the skin arise in several distinct variants that can be classified as either multibacillary or paucibacillary; each subtype within these categories presents with its own morphological and histological findings. The diagnosis of CTB can prove clinically challenging as its variants mimic many conditions dermatologist encounter on a daily basis. Additionally, tissue confirmation is difficult. We report a case of CTB which evolved from a lupus vulgaris presentation to the metastatic tuberculous abscess variant.

Tumefactive foreign body giant cell reaction following high-pressure paint injection injury: A case report and review of literature.

High-pressure paint injection injury is an uncommon but well-described injury. The histologic features of long-term paint injection injury with retained material are less recognized. A 46-year-old male presented clinically as "recurrent giant cell tumor of tendon sheath." The right index finger demonstrated fusiform enlargement by a pigmented mass with diffuse infiltration into the soft tissue of the hand. Histologically the tumor showed multiple giant cells in a fibrotic stroma extending into the dermis. There were multiple types of foreign material including diffuse brown black pigment, weakly optically polarizing foreign material and white inclusions with a "train track" appearance. The cells were positive for CD68 and negative for S100 antigen. Further investigation revealed that the patient had a history of high-pressure paint injection injury to his digit 6 years prior. Foreign material injected under high pressure into tissues may result in a pseudo-neoplastic foreign body granulomatous reaction that can mimic giant cell tumor of tendon sheath. Our case demonstrates that this reaction can be florid and can have slow growth over years. A high index of suspicion, a good clinical history and careful examination can distinguish these 2 entities.

Multiple eccrine spiradenomas in a zosteriform pattern.

Eccrine spiradenoma (ES) typically presents as a solitary tender lesion. Multiple ES is a rare variant of ES and can present in a segmental, linear, blaschkoid, or zosteriform pattern. The etiology of multiple ES is unknown, but several theories have been suggested including a multipotent stem cell origin. We report the case of a 30-year-old woman with multiple painful ES in a zosteriform pattern on the mid-back and abdomen. Skin biopsy of a representative lesion demonstrated a circumscribed tumor nodule encapsulated by a fibrous capsule with diffuse dense basophilic proliferation located in the dermis. The lesions were then excised on two separate sessions without recurrence.

Dermatofibrosarcoma protuberans with unusual sarcomatous transformation: a series of 4 cases with molecular confirmation.

Dermatofibrosarcoma protuberans (DFSP) is a superficial sarcoma of intermediate malignancy usually composed of monotonous short spindle cells with storiform architecture. The tumor cells are diffusely reactive for CD34 and characterized by a translocation involving chromosomes 17 and 22 or a supernumerary ring chromosome that results in the fusion of exon 2 of platelet-derived growth factor beta (PDGFß; 22q13) to various exons of collagen type 1 alpha 1 (COL1A1; 17q22). In some tumors, fibrosarcomatous transformation can occur and is characterized by a monotonous spindle cell proliferation arranged in fascicles or a herringbone-type pattern. We report 4 DFSPs with unusual and pleomorphic sarcomatous transformation. They occurred on the back, scalp, shoulder, and forehead of women (ages 31,48, 48, and 27 year). In addition to areas of conventional DFSP that strongly expressed CD34, 2 cases showed pleomorphic areas mimicking undifferentiated pleomorphic sarcoma/malignant fibrous histiocytoma: 1 case had a patternless area and 1 case had combined round/spindled cells with myxoid areas. Reverse transcription--polymerase chain reaction was performed in 1 case, confirming the presence of a COL1A1-PDGFß fusion transcript. The remaining three cases were found to be positive for a PDGFß gene rearrangement by fluorescence in situ hybridization. This series illustrates that sarcomatous transformation in DFSP may occasionally display areas, which can mimic undifferentiated pleomorphic or unclassified sarcoma. Ancillary diagnostic testing may be helpful to confirm the diagnosis, especially in small biopsies.