True histiocytic lymphoma of the stomach associated with low-grade B-cell mucosa-associated lymphoid tissue (MALT)-type lymphoma.

True histiocytic lymphoma is considered a rare entity, and its diagnosis requires the concordance of morphological, immunophenotypic, and molecular findings. The association of malignant lymphoma with tumors in the monocyte-macrophage system has rarely been described. We present a case of mucosa-associated lymphoid tissue (MALT)-type low-grade B-cell lymphoma of the stomach, contiguous to a large tumoral mass that fulfills the morphological criteria (large cells with abundant pale cytoplasm and lobulated or kidney-shaped nuclei) and immunophenotypical features (human leukocyte antigen-DR locus, CD68, S-100, lysozyme immunoreactivity, and negative B- and T-cell markers) required for the diagnosis of histiocytic lymphoma. The patient remains in complete remission 18 months after surgery. The association of low grade-malignant lymphoma with tumors of monocyte-macrophage system cells is an exceedingly rare phenomenon. Whether these tumors are directly related or occur due to pure chance requires the identification of new cases and further study.

Hormonal receptors, cell proliferation fraction (Ki-67) and c-erbB-2 amplification in breast cancer. Relationship between differentiation degree and axillary lymph node metastases.

In view of the limitations of conventional prognostic factors such as differentiation degree, metastatic lymph nodes, hormonal receptors and others, especially when early lesions are found, additional new markers have been studied, such as gene amplification and cell proliferation index, in order to choose the appropriate treatment. Primary breast carcinoma tumors from 97 patients were examined for differentiation degree, metastatic lymph nodes, hormonal receptors, c-erbB-2 amplification and cell proliferation index (Ki-67). A negative relationship with hormonal receptors and c-erbB-2 amplification, Ki-67 and differentiation degree was found, whereas the relationship between c-erbB-2, Ki-67 and differentiation degree was positive. No relationship was found between these factors and metastatic lymph nodes. The concurrence of high cell proliferation index, c-erbB-2 amplification and negative hormonal receptor presence would indicate a subpopulation with a high risk of recurrence. But a larger survival study is necessary to correlate these factors with clinical outcome.

p53 in breast cancer. Its relation to histological grade, lymph-node status, hormone receptors, cell-proliferation fraction (ki-67) and c-erbB-2. Immunohistochemical study of 153 cases.

The mutation of the p53 gene is a common phenomenon in numerous human tumors, leading to the accumulation of nonfunctioning p53 protein in the cell nucleus, which can be detected by immunohistochemistry. In breast cancer, it has been suggested that the overexpression of p53 protein in the nucleus is an indicator of poor prognosis, which must be borne in mind in selecting coadjuvant treatment for each patient. This study is an immunohistochemical analysis of p53 expression in 153 cases of mammary carcinoma, correlating it with histological grade, axillary node status, hormone receptors, cell-proliferation fraction and expression of the c-erbB-2 oncoprotein. Of all the breast-cancer tissue analyzed, 43.79% was positive for p53. The overexpression of this protein bears a direct statistically significant relationship to histological grade, cell-proliferation fraction and c-erbB-2, and an inverse relationship to estrogen and progesterone receptors. No statistically significant relationship was found with axillary node status. The expression of p53 in poorly differentiated tumors-commonly receptor negative and with a high proliferation fraction-may indicate greater tumor aggressiveness and a high risk of relapse.

Inflammatory myofibroblastic tumour of larynx.

Inflammatory myofibroblastic tumour (IMT) is a benign pseudoneoplastic proliferation, mainly developing in the lung and extremely rare in the larynx. A patient with a two-month history of dysphonia and a polypoid left true vocal fold tumour is presented. Histological and clinical knowledge of this lesion is important to exclude a misdiagnosis (e.g. malignant epithelial or mesenchymal tumours) and an inappropriate treatment.