No abstract

A case of intracerebral schwannoma (ICS) occurring in a 33-year-old woman is presented. The patient's history of headache, numbness, tingling and the recent development of weakness of the right upper extremity with right facial droop began during pregnancy. Magnetic resonance imaging (MRI) showed a 4 x 2 x 2 cm heterogeneous, gadolinium-enhanced mass at the left frontoparietal junction, with peritumoral edema and a dural-based attachment. During her pregnancy, the mass increased in size. The surgically resected specimen consisted of lobulated, somewhat gelatinous soft tissue. Microscopically, the tumor demonstrated classic biphasic Antoni type A and B patterns, admixed with degenerative changes. Immunohistochemically, the neoplastic cells were positive for S-100 protein (diffuse and strong), CD34 (primarily in Antoni B areas), glial fibrillary acidic protein (GFAP; weak and diffuse) and calretinin (mainly in Antoni A areas), while none was positive for CD31, estrogen and progesterone receptors, bcl-2, or epithelial membrane antigen (EMA). Ultrastructurally, basal laminae and Luse bodies were identified. The differential diagnosis includes fibrous meningioma, solitary fibrous tumor, and ICS. Twenty-seven cases of ICS were reviewed in which the histological diagnosis was confirmed immunohistochemically or ultrastructually, and the cases were summarized (including the present case). A combined use of immunostains (S-100 protein, EMA, CD34, and maybe calretinin) is of great help in distinguishing ICS from its histological mimickers.

A 40-year-old Caucasian man presented to the dermatology clinic at Baylor College of Medicine, Houston, Texas, in February 2003, for the evaluation of three nonhealing ulcers. The patient's past medical history was significant for hypothyroidism and pulmonary sarcoidosis, the diagnosis of which was made in June 2000. In March 2000, the patient had complained of cough and shortness of breath. A purified protein derivative (PPD) (Mantoux text) was negative. Computed tomography (CT) scans of the chest revealed diffuse hilar and mediastinal adenopathy and bilateral interstitial and alveolar infiltrates. Although consistent with sarcoidosis, these findings were insufficient to exclude other etiologies, including disseminated fungal infection. Cultures and stains of subsequent bronchoscopy specimens failed to reveal any organisms, and histopathologic evaluation of the specimens was nondiagnostic. Based on the imaging studies and the negative cultures, a diagnosis of sarcoidosis was made, and the patient was started on therapy with prednisone. Before coming to our clinic, the patient had been on several courses of prednisone. In May 2002, the patient had presented to a private dermatologist with a 1-year history of a nonhealing 2.4 cm x 2.0 cm ulcer on the left medial forearm. Two biopsies were reported as nondiagnostic. The patient's presentation was interpreted as most consistent with Mycobacterium marinum infection, and so he was empirically treated with minocycline. This treatment was continued for almost 3 months without improvement in the ulcer. A few months after the minocycline had been discontinued, the patient was treated empirically for 2 months with ciprofloxacin. This treatment was also unsuccessful in ameliorating the ulcer. In between the two courses of antibiotics, specimens from the lesion were sent for bacterial and fungal cultures, which revealed normal skin flora. In January 2003, the patient returned to his private dermatologist with three ulcerations. In addition to the nonhealing ulcer on his left forearm, which he had acquired several months earlier, he had also developed a 3.0 cm ulcer on his right arm and a 3.0 cm ulcer on his central back. The patient refused biopsies at this visit. Given the patient's previous diagnosis of pulmonary sarcoidosis, it was thought that the skin lesions might represent ulcerative cutaneous sarcoidosis. Pyoderma gangrenosum was also considered to be a likely diagnosis. Therefore, the patient was started on a course of oral prednisone, an effective therapy for both sarcoidosis and pyoderma gangrenosum. Despite 1 month of treatment with 60 mg/day of prednisone, the ulcers increased, and the patient was subsequently referred to our clinic. Physical examination at the time of presentation revealed steroid acne on the trunk and upper extremities and three non-tender ulcers with erythematous, undermined borders (Figs 1-3). On the left arm, there was an adjacent nodule which the patient attributed to a scar from a previously healed ulcer. Histologic examination of biopsy ...