[Benign fibrous mesothelioma: report of 8 cases]. / Mesotelioma fibroso benigno: aportación de 8 casos.

Benign fibrous mesothelioma (BFM) is a primary, isolated tumor of the pleura. In 80% of patients the tumor originates in the visceral pleura. BFM is rare and localized malignant mesothelioma, whose prognosis and treatment is significantly different, must be considered as a differential diagnosis. We report 8 cases of BFM excised by thoracotomy. In 6 asymptomatic patients, diagnosis was based on radiological images. One patient with a large tumor suffered dyspnea, acropachia and hypertrophic osteoarthropathy. The last patient experienced long-lasting chest pain even though the tumor was small (3 x 3 x 1 cm). Diagnosis was before thoracotomy in 3 cases, 2 by punch biopsy (tru-cut) and the other by thoracoscopy. The results of pleural fluid analysis were nonspecific in 2 of the 3 cases in which pleural effusion was present. Thoracotomy allowed removal of the entire tumor in all patients.

[Inflammatory-type malignant fibrohistiocytoma of the mesocolon associated with colonic parasitosis due to Trichocephalus]. / Fibrohistiocitoma maligno de tipo inflamatorio de mesocolon asociado a parasitosis colónica por tricocéfalos.

A case of inflammatory malignant fibrous histiocytoma of the mesocolon is reported. The lesion presented as a right lower quadrant abdominal mass, located at the mesocolon, with obstructive symptoms and accompanied by a severe infestation by Trichuris trichiura. It had a benign histologic appearance and was considered initially as an inflammatory and necrotic process with severe tissue eosinophilia secondary to the severe parasitosis. The tumor relapsed 13 months later at the anastomotic site and the patient died. Diagnostic, prognostic and therapeutic aspects of this rare tumor are discussed.

Amyloidosis presenting as a perforated giant colonic diverticulum.

Colonic amyloidosis is frequent, although rarely radiographically evident. The radiological findings are varied and unspecific. We report a case of perforated giant colonic diverticulum (GCD) diagnosed by helical CT in which amyloid deposition was pathologically demonstrated. The patient was a renal transplant recipient who previously had undergone hemodialysis for 10 years. A possible role of amyloidosis in the pathogenesis of this case is discussed. Giant colonic diverticulum must be included in the spectrum of gastrointestinal manifestations of amyloidosis.

A cutaneous multilobated B-cell lymphoma.

A patient with multilobated B-cell malignant lymphoma with lesions limited to the skin is described. The light, electron microscopic, and immunohistochemical features of this unusual morphologic variant of non-Hodgkin's lymphoma are described. The nosologic position of this histologic subtype is discussed. The clinical course, with lesions confined to the skin, and the response to treatment suggest a favorable prognosis.

Multiple linear cylindromas.

We report a case of multiple cylindromas with a linear arrangement on the lower right extremity. The patient had more than 100 tumors, but the scalp was spared. Some tumors showed overlapping features with eccrine spiradenoma. We believe this is the first report of multiple linear cylindromas.

Systemic lupus erythematosus presenting with a reticular erythematous mucinosis-like condition.

We report the case of a woman with clinical and histopathological features of reticular erythematous mucinosis syndrome (REM) who six years later developed diagnostic criteria for systemic lupus erythematosus (SLE). Two biopsies performed at the same area initially showed mucin dermal deposits and further development of characteristic dermo-epidermal changes of lupus erythematosus. Our findings suggest that SLE may present with an REM-like condition.

Syphilis in an HIV infected patient misdiagnosed as leprosy.

A 42-year-old man with uveitis and a widespread cutaneous eruption, histopathologically characterized by dermal granulomatous infiltrates with perineurial invasion, was incorrectly diagnosed and treated as having borderline leprosy. Further studies demonstrated secondary syphilis and human immunodeficiency virus (HIV) infection. Standard penicillin therapy resolved his cutaneous and ocular lesions. Reports on clinical and pathological findings of active syphilis in HIV infected patients are scarce but this case and isolated previous case reports suggest that granulomatous infiltrates might be a common feature in secondary syphilis with short evolution in HIV infected patients.

Reticular erythematous mucinosis syndrome. Report of a case with positive immunofluorescence.

We report a case with the clinical and histological features of the reticular erythematous mucinosis syndrome (REM), in which there was moderate, continuous, fine, granular, IgM deposition along the basal layer. Similar direct immunofluorescence results have been reported in only two previous cases.

Olmsted syndrome.

Olmsted syndrome is an uncommon inherited disorder of keratinization that presents mutilating palmoplantar keratoderma, perioral hyperkeratosis, leukokeratosis and alopecia. We report a case of this rare syndrome diagnosed in a 48-year-old woman and confirms the existence of a generalized abnormality in keratin expression. Immunoreactivity in our case suggests an abnormal expression of keratins 5 and 14 similar to the observed in other hyperproliferative disorders.