Malignancy-associated Changes Research Articles

Malignancy associated changes (MACs) in bronchial epithelial aspirates and biopsies : C. MacAulay, ∗P. Payne, S. Lam, D. Haskins, B. Palcic. Cancer Imaging, Medical Physics Division, British Columbia Cancer Agency and ∗Xillix Technologies Corp., Vancouver, British Columbia, Canada

Malignancy associated changes (MACs) in bronchial epithelial aspirates and biopsies : C. MacAulay, ∗P. Payne, S. Lam, D. Haskins, B. Palcic. Cancer Imaging, Medical Physics Division, British Columbia Cancer Agency and ∗Xillix Technologies Corp., Vancouver, British Columbia, Canada

Detection and Localization of Early Lung Cancer by Imaging Techniques

Two new technologic developments may have a significant impact on the detection and localization of early lung cancer. These two developments work together in a complementary way. The first is a solid-state microscope that can be applied in the prescreening of sputum cytology specimens. The finding that malignancy-associated changes (MACs) are present in ostensibly normal bronchial epithelial cells may be used to improve the sensitivity of sputum cytology to detect cancer. Once abnormal or MAC cells are found, a second device, a fluorescence bronchoscope, can be employed to localize the source of the abnormal cells. Fluorescence bronchoscopy is also a potentially useful tool for procuring premalignant tissue for molecular biology studies and for monitoring the progress of patients in chemoprevention studies.

Significance of histopathology in pulsed NMR studies on cancer.

Characterization of tissue by pulsed nuclear magnetic resonance spectrometry opened a new area of research. The differences in the NMR parameters T1 and T2 of normal and malignant tissues constitute the basis for their distinction by pulsed NMR spectrometry and also by NMR imaging in vivo. The present studies were undertaken to correlate the role of constituent histological elements encountered in various malignancy-associated changes and T1 variations and are based on evaluation of samples taken from surgically resected specimens of carcinoma of the esophagus, comprising the uninvolved portions of the esophagus and the gastric end on gross examination. The uninvolved and involved regions showed low and high T1 values, respectively. High T1 values were also encountered in the zones of samples of uninvolved esophagus which histologically revealed areas with dysplasia. This feature, viz., dysplasia representing malignancy-associated changes, has been found to recur in many samples. Detailed histological studies provided further evidence confirming that areas with dysplasia contribute to an increase in T1 values whereas in zones at the gastric end metaplasia and hyperplasia are more common. The results are of value for demarcation of tumor area by in vivo NMR imaging.

Diagnostic Cell Pathology in Tissue and Smears

This meticulous work draws from the author's vast experience in clinical cytopathology. It sets forth his principles and concepts used in interpreting morphology, and in diagnosing states and lesions encountered in clinical medicine. Cellular structures in histologic and cytologic preparations are described in detail and are correlated in a superb collection of photomicrographs of high quality. General cellular structures and their alterations associated with normalcy, inflammation, hyperplasia, atrophy, malignant transformation, and malignant tumors are covered in detail. Diagnostic significance of the morphologic alterations is discussed, and their clinical applications are evaluated. Thoroughly reviewed is the author's work on malignancy-associated changes (MAC). Interpretation of these minute structural alterations still remains extremely subjective; thus, this detailed presentation is probably not sufficient for them to bear much clinical application at the present time. For investigation in this field, however, this section will prove to be invaluable. Clinical cytological techniques are presented in

Diagnostic Cell Pathology in Tissue and Smears.

Among pathologists there is an old saying: High power microscopy, low power pathology. This approach works well in tissue work; but according to the author of this text, it makes cytology reports unnecessarily vague. If I correctly interpret his book, he would adapt the adage to read as follows: Oil immersion microscopy, high power cytology. Doctor Nieburgs, a pathologist at Mount Sinai School of Medicine, has scrutinized hematoxylin and eosin stained cells under the oil immersion lens for 12 years. This technic, he says, lets him look closely enough at the nucleus to sharply differentiate benign and malignant cells. He uses criteria he calls MAC (malignancy associated changes). These include nuclear cytoplasmic ratio, chromocenters and chromatin bands, nuclear clear areas, nucleoli, and multinucleated cells. Once he has studied these, he reports diagnoses ... in terms of pathological tissue alterations. In other words (and here it seems to me is his main

The morphology of cells in duodenal-drainage smears: histologic origin and pathologic significance.

Duodenal-drainage smears from 301 patients were examined. Of these, 73 patients had pancreatic carcinoma, while 32 patients had malignant tumors at other sites. Malignant tumor cells were found in 23 cases of pancreatic carcinoma and in 7 patients with carcinoma of the gallbladder and common duct. Atypical cells of pancreatic ductal origin and having neoplastic significance were present in 16 cases of 13 patients with pancreatic carcinoma. Malignancy-associated changes in cells of undetermined origin were seen in 29 patients with pancreatic carcinoma and in 19 with malignant tumors at other sites. Of 25 specimens with equivocal cells, carcinoma of the pancreas and common duct was present in 4 patients. Three patients of 135 with negative cytologic specimens had pancreatic carcinoma.