A subset of cell clusters with malignant features in morphologically normal-appearing and hyperplastic tissues.

Background: The development of human breast cancer may be a multistep process, sequentially undergoing normal, hyperplastic, in situ, invasive, and metastatic stages.

Methods: Our previous and current studies have revealed that a subset of morphologically normal-appearing and hyperplastic breast tissues adjacent to or distant from malignant breast lesions contained cell clusters that showed malignancy-associated immunohistochemical and cytological alterations.

Results: Compared to their morphologically similar counterparts within the same lesion, these cell clusters exhibited several unique features: (1) a significantly increased frequency of focal disruptions in surrounding myoepithelial cell layers and the loss of estrogen receptor expression, (2) signs of stromal and vascular invasion, (3) distinct alterations in the cytoplasmic-nuclear ratio and nuclear shape, size, and polarity, (4) the expression of multiple malignancy-associated biomarkers, and (5) malignancy-associated nuclear changes in benign-appearing cells.

A subset of in situ breast tumor cell clusters lacks expression of proliferation and progression related markers but shows signs of stromal and vascular invasion.

Background: Our previous studies in pre-invasive mammary tumors revealed that estrogen receptor negative cell clusters (ER NCC) overlying focally disrupted myoepithelial (ME) cell layers showed a significantly higher rate of genetic abnormalities and cell proliferation than adjacent cells without ME cell layer disruptions. A subset of these ER NCC, however, completely lacked expression of Ki-67, a most commonly used marker for cell proliferation. The purpose of this study was to further elucidate the immunohistochemical and morphological profiles of these ER NCC.

A decision support system to detect morphologic changes of chromatin arrangement in normal-appearing cells.

Several studies have described malignancy-associated changes (MACs) of chromatin arrangement in the nuclei of apparently normal cells adjacent to and distant from an invasive cancer area. MAC assessment is a hard task, since it requires a deep knowledge of morphologic features of chromatin arrangement. The aim of this work is to verify the reproducibility of the subjective evaluation of the expert on the basis of a decision support system (DSS) that automatically and objectively reproduces MAC diagnosis.

Relationship between the in vitro colony growth of human tumors and cytologic diagnosis.

The cytologic examinations and cloning efficiencies of 47 human tumor specimens (19 ovarian carcinomas, 6 sarcomas, 5 lung carcinomas, and 17 miscellaneous tumors) were compared to evaluate the predictability of clonogenecity by cytologic diagnosis. Cytologic examination preceding clonogenic assay identified the 50% to 60% of all specimens that failed to yield in vitro chemotherapy sensitivity by this assay, with a false-negative rate of 10%. The frequency of cytologically identifiable tumor cells in the plating suspension was independent of the histologic type of tumor (ovarian carcinoma or others) and the nature of the specimen (solid tumor or malignant effusion).

Problems in the diagnosis of small cell carcinoma of the lungs by fiberoptic bronchoscopy.

Fiberoptic bronchoscopy (FOB) with the aid of endoscopic biopsies and brush cytology is recognized as a valuable approach in the diagnosis of lung cancer. However, histologic classification of lung cancer based on tiny specimens obtained from FOB can be difficult. Correct identification of small cell carcinoma of the lung is especially important because its recognition usually precludes surgery.