Computed tomography-guided fine-needle aspiration biopsy.

The therapeutic and prognostic evaluation of malignant neoplasias depends largely upon a precise morphologic diagnosis. Several papers have focused on the importance of fine-needle aspiration under computed tomography guidance in the diagnosis of unresectable neoplasms and in the investigation of metastases. The objective of this study is to evaluate the diagnostic accuracy, the sensitivity, and the negative predictive value obtained with the technique. Fine-needle aspiration cytology (FNAC) was performed on 207 patients, with a total of 210 cases, from 1991 to 1994, under computed tomography (CT) guidance. There were 128 (61.8 percent) males and 79 (38.2 percent) females with a mean age of 41 years (range 1 to 91 years). Lung and liver were the most frequent anatomic sites. The analysis of this material disclosed 41 cases with cytological diagnosis of negative for malignancy (19.52 percent), and in 131 (62.38 percent), the diagnosis was positive. It was possible to define the cytologic lineage in 54 percent of the cases. The diagnosis in 14 (6.67 percent) cases was suspicious for malignancy, and in 24 (11.43 percent) cases the material was insufficient for the cytologic diagnosis. Of the 210 cases, 106 showed histological diagnosis and/or clinical follow-up. Forty-seven (44.3 percent) had histological diagnosis before the FNAC and 50 cases (56.7 percent) histological diagnosis after the procedure. The comparison between cytological and histological diagnosis showed a sensibility of 80.4 percent, specificity of 100 percent, positive predictive value of 100 percent and negative of 16.7 percent. The efficiency of the test was 81.1 percent. This study showed that FNAC, under computed tomography guidance, is a sensitive and specific technique for the diagnosis of deep-seated lesions.

Cytologic diagnosis of melanoma in serous effusions. A morphologic and immunocytochemical study.

The diversity of melanoma patterns greatly impairs the interpretation of malignant cells in effusion samples. The presence of melanin pigments greatly helps determine the histogenetic origin of the tumor, but unfortunately many cases do not exhibit this feature. We reviewed cases with a definitive diagnosis of melanoma in order to identify some useful characteristics of the morphologic examination of effusions. We also subjected the effusions to the HMB45 immunoreaction to determine the diagnostic usefulness of this monoclonal antibody. The study was performed on 21 effusion samples containing malignant cells, and the main cytologic findings were similar to those on other neoplasms except for the presence of melanin pigment. The HMB45 immunoreaction was very sensitive, confirming the diagnosis in 14 of 18 cases (77.8%). Melanin pigments seem to be useful markers for melanoma in effusions, and HMB45 can be used as an ancillary method in the differential diagnosis.

Inflammatory fibroid polyp. Review of the literature.

Inflammatory fibroid polyp is a rare polypoid lesion of the gastrointestinal tract, histologically characterized by a mixture of proliferation of fibroblasts and small blood vessels, accompanying a marked eosinophilic infiltrate. The lesion largely affects adults and is more common in the antrum of the stomach, but have occasionally been reported in the small bowel and colon. Clinical symptoms are variable, depending on the location and size of the lesion. Although it is generally believed to represent a reactive, nonneoplastic condition, their histogenesis remains controversial. The pathological features, hypothesis about pathogenesis and etiology, ultrastructural and immunohistochemical findings are discussed in this review of the literature.