A rare variant of extraskeletal osteosarcoma presenting as a clinically benign subcutaneous neoplasm.

Extraskeletal osteosarcoma (ESOS) is a rare variant of osteosarcoma that arises without attachment to the underlying skeleton. These cancers are typically found embedded in deeper tissues, most commonly the muscle or fascia, and are rarely found within the skin or subcutis. Most tumors are large in size upon initial presentation, and carry a poor prognosis. We discuss the case of a 48-year-old Caucasian woman who presented to a dermatology clinic with an asymptomatic, small, mobile, subcutaneous mass that appeared clinically benign. After elective removal and histopathologic examination, the patient was diagnosed with ESOS. ESOS presenting in this manner is exceedingly rare, and this case highlights the importance of sending all excised specimens, even those with a benign presentation, for pathologic examination.

Primary cutaneous histiocytoid carcinoma with distant metastasis.

Distinguishing primary cutaneous adnexal carcinoma from metastatic carcinoma of unknown primary can be a diagnostic challenge due to the frequent overlap of histologic and immunohistochemical features. A 58-year-old man presented with a tender, indurated plaque on axillary skin. Biopsy revealed infiltrating atypical cells throughout the dermis, without connection to the epidermis. Tumor cells had a histiocytoid appearance and displayed mild pleomorphism. The tumor was discohesive and had areas with a single file pattern. Signet ring cells were also present. Cells were reactive with CK7, CK5/6, p63, GATA3, GCDFP-15 and Her 2-neu. Additional studies were negative, including TTF-1, CDX2, E-cadherin, mammaglobin, estrogen receptor and progesterone receptor. Thorough clinical and radiologic evaluation failed to identify an occult primary extracutaneous malignancy; however, regional lymphadenopathy, widespread osteoblastic lesions and multiple subcentimeter liver hypodensities were noted. Considering the clinical and histopathologic features, the diagnosis of primary cutaneous histiocytoid carcinoma with distant metastasis was favored.

Dual S-100-AE1/3 Immunohistochemistry to Detect Perineural Invasion in Nonmelanoma Skin Cancers.

Background. Perineural invasion (PNI) is an adverse prognostic histologic finding and increases the risk of local recurrence and metastasis. Objective. We aimed to determine if dual immunohistochemical (IHC) staining with S-100 and AE1/3 would increase the detection of PNI on nonmelanoma skin cancers (NMSCs). Methods. We collected 45 specimens of NMSCs in which there was clinical suspicion for PNI. Two dermatopathologists independently reviewed the tumors for the unequivocal presence of PNI. Results. Unequivocal PNI was present on 10 of the 45 tumors by H&E staining and on 15 of the 45 tumors by IHC staining. Large nerves (>0.1 mm) were involved in 3 of 10 H&E-stained cases and 3 of 15 IHC-stained cases, with 2 of the 4 cases demonstrating large nerve involvement with both staining methods. Of the 8 cases of PNI detected only on IHC, 7 were small nerves (≤0.1 mm). Limitations. All cases were selected because they were clinically suspicious for PNI, and this may be considered selection bias. Conclusions. PNI detection may be increased using dual S-100 and AE1/3 staining, but the majority of additional cases detected were small nerves. The clinical significance, given the small size of the involved nerves, is unclear.

Spitz nevus in a Hispanic population: a clinicopathological study of 130 cases.

Spitz nevus is an uncommon melanocytic nevus distinctive by its epithelioid and spindled melanocytes. Many studies have attempted to characterize Spitz nevus, but none of them in a Hispanic population. Our aim is to characterize the clinical and histopathological presentation of the Spitz nevus in a Hispanic population. A retrospective study was carried out from our files that included those cases histopathologically diagnosed as Spitz nevus. A blinded examination was performed to evaluate the histopathological characteristics of 130 lesions. The demographics of the patients, the anatomic location, and the accuracy of the clinical diagnosis were analyzed. Eighty-one females and 49 males (ratio of 1.7:1) were included in the study. The mean age was 18.8 years. Overall, the most common location was the lower extremities (41%), followed by the upper extremities (27%), trunk (16%), and head and neck (16%). The nevi followed a similar anatomic distribution in females and males. The lesions were clinically diagnosed with accuracy in 20% of the cases and characterized as a pigmented papule in 42% of the cases. Upon histopathological evaluation, most nevi exhibited symmetry (84%), were well circumscribed (91%), and exhibited epidermal hyperplasia (69%). The junctional type was seen in 42% of the cases, the compound type in 38%, and the dermal type in 20%. Sixty-eight percent of nevi were mostly composed of epithelioid melanocytes, the spindled-shaped melanocytes predominated in 17% of cases, and 12% were composed of both epithelioid and spindled-shaped melanocytes. Multinucleated melanocytes were seen in 7% of nevi, mostly in the epithelioid Spitz nevus (67%). Abundant melanin was observed in 51 cases, from which the most common variant was the classic Spitz nevi. The typical dull eosinophilic globules (Kamino bodies) were observed in a minority of the cases (11%), mostly in the classic Spitz nevus. The most common variant was the classic Spitz nevus (65%), followed by the dermal Spitz nevus (15%). In conclusion, Spitz nevus in a Hispanic population most commonly presents as a pigmented papule on the lower extremities irrespective of sex and age. It is characterized by a melanocytic proliferation most commonly composed of nested epithelioid melanocytes in a junctional or compound arrangement, with the presence of abundant melanin.

Nodular mucinosis of the breast in a supernumerary nipple: case report and review of the literature.

Nodular mucinosis is an extraordinary stromal lesion of the breast. The usual clinical presentation is that of an oozing, slow-growing, soft, non-tender, lobulated mass in the subareolar region. Histologically, it is a non-encapsulated myxoid/mucinous lesion with a sparse infiltrate of spindle cells within a collagenized stroma. The histogenesis of nodular mucinosis is undetermined but the pattern of staining of the spindle cells suggests it might be of myofibroblastic origin. We herein report for the first time in the English literature a case of nodular mucinosis occurring in a supernumerary nipple. We also discuss the main differential diagnoses and review the literature of previously published cases of this entity.

Pattern analysis of drug-induced skin diseases.

Drug eruptions are common adverse reactions to drug therapy and are a frequent reason for consultation in clinical practice. Even though any medication can potentially cause an adverse cutaneous reaction, some drugs are implicated more commonly than others. Histologically, drugs can elicit a variety of inflammatory disease patterns in the skin and panniculus, no pattern being specific for a particular drug. The most common pattern elicited by systemically administered medications is the perivascular pattern. Psoriasiform or granulomatous patterns are rarely caused by medications. The usual histologic patterns of drug eruptions are discussed in this review using the basic patterns of inflammatory diseases. Clinicopathologic correlation is established for relevant patterns. However, the changes of drug-induced skin disease must be made considering clinical presentation, histopathological analysis, and course of the disease.

Granulomatous rosacea.

Rosacea is classified into four clinical subtypes, namely erythematotelangiectatic, papulopustular, phymatous, and ocular. There is also a granulomatous variant, which is recognized in the rosacea spectrum. The objective of this study is to take a closer look at the different histopathologic patterns and cellular compositions seen in granulomatous rosacea and their correlation to the clinical presentation. Facial biopsies from patients previously identified with a clinical diagnosis consistent with rosacea, and who demonstrated a granulomatous infiltrate upon histopathologic examination, were reviewed and the results were correlated to the clinical presentation. Four distinct histopathologic granulomatous patterns were identified, namely nodular, perifollicular, diffuse, and a combined perifollicular and nodular patterns. The clinical presentation varied greatly among patients and failed to correlate to the microscopic findings. The varied clinical features seen in our study favors the theory that granulomatous rosacea is not a clinical subtype of rosacea per se, but a distinct histological variant, which can be found in most of its clinical spectrum.

Disease evolution of patients with mycosis fungoides--a report of 30 cases.

Mycosis fungoides is the most common disease of the primary cutaneous T-cell lymphoma group. This is a retrospective study to evaluate the outcome of 30 patients with mycosis fungoides who were followed up for at least 3 years, 18 of them followed for 5 years and 9 of them followed for 7 years. A total of 10 patients achieved a sustained remission, 2 patients achieved a remission but then relapsed and three patients died from lymphoma-related death. It is concluded that the majority of the patients with T1 or T2 stage MF usually have a good prognosis. As a rule, those who do progress further in the disease have advanced stages at the moment of the diagnosis; the disease progression occurring during the first 3-5 years after diagnosis.

Puerto Rico psoriasis study group: efficacy and safety of etanercept.

BACKGROUND: Although major advances in the understanding of its pathogenesis have been achieved, psoriasis remains an incurable disease. In April 2004, etanercept, an antagonist of TNF-alpha, was approved by the Food and Drug Administration for the treatment of chronic, moderate to severe plaque psoriasis in adults. In this study we intend to document the efficacy and further establish the safety profile of etanercept for the treatment of moderate to severe psoriasis in our population and compare our data to the Leonardi et al study published in 2003. METHODS: A total of 26 patients were followed for a period of 24 weeks. Subjects were administered 25 mg of etanercept subcutaneously twice weekly for 24 weeks. Patients were seen every 4 weeks to measure clinical improvement by means of the psoriasis area and severity index (PASI) scores. Development of side effects was also assessed. RESULTS: Ninety-two percent of the patients had an improvement of greater than 50% in their PASI score, with 79% of these patients with a PASI improvement of 75% or greater. Adverse events were uncommon and none required the permanent discontinuation of treatment. CONCLUSION: Treatment with etanercept was well-tolerated and resulted in significant sustained improvement of psoriasis throughout a period of 24 weeks. Our data strongly correlates with the findings reported by Leonardi et al in 2003.