Remodeling of coronary arteries in human and nonhuman primates.

OBJECTIVE: To compare coronary artery remodeling (compensatory enlargement) in human and nonhuman primates. DESIGN: Coronary artery data were analyzed retrospectively for 416 nonhuman primates and 100 men and women. SETTING: The monkeys had been in experiments involving diet-induced coronary artery atherosclerosis. The human hearts were obtained from the North Carolina Baptist Hospital, Winston-Salem, and age greater than 25 years was the only criterion. PATIENTS AND OTHER PARTICIPANTS: The left anterior descending coronary arteries from 100 humans, 328 cynomolgus monkeys, and 88 male rhesus monkeys were used. INTERVENTIONS: None; this was a cross-sectional observational study. MAIN OUTCOME MEASURES: Coronary artery size, lumen area, and plaque size. In the humans, we also examined demographic characteristics (ethnicity, sex, and history of hypertension) and pathologic criteria (eccentricity or concentricity of plaque area). RESULTS: On average, lumen size remained unaffected by plaque size. Lumen size was variable and could not be predicted by traditional risk factors for coronary heart disease. However, lack of compensation (decreased lumen size as plaques enlarged) and history of coronary heart disease were significantly correlated. CONCLUSIONS: The similarity of remodeling in human and nonhuman primates suggests that the process has general biologic significance. Lack of remodelling may be a major determinant of whether a person with coronary artery atherosclerosis develops its complications.

Pathology trainee manpower. Historical perspectives.

Discussions of pathology manpower typically involve short-term projections. For example, the best current data indicate a significant shortage of community-hospital/private-laboratory pathologists over the 5-year period from 1988 through 1993. Even though such short-term predictions are important in the debate over strategic planning in pathology, they need to be placed in a broader historical context. Therefore, we present the long-term trends in pathology trainee manpower. These trends indicate why predictions of a shortage should not come as a surprise.

Pathology trainee manpower: APC program directors' questionnaire, 1989 results.

The shortage of pathologists is being created by a combination of three factors: inadequate trainee recruitment, high trainee attrition, and accelerating practitioner attrition. The current report provides comprehensive data on the first two factors. The third factor is, by every estimate, likely to become worse over the decade beginning in 1988. Demographics show that greater numbers of pathologists will be reaching retirement age every year. The trainee attrition problem appears to be very serious, and we currently do not have data on why residents leave pathology training, when they leave, or where they go (ie, to what other specialties, etc). Future APC program directors' questionnaires must address these issues. Yet, we must also solve a serious problem in recruitment. Currently, about 35% to 38% of all first-year pathology residents decide to enter pathology only after entering residency programs in other specialties with the intent to remain in that specialty. Therefore, we need to recognize both the problem of inadequate recruitment and the problem of high attrition in order to address the serious manpower shortage facing pathology. When shortages occur in specialties, practitioners tend to cease performing the most time-intensive tasks (eg, autopsy). However, shortages of the magnitude predicted for pathology suggest that many more tasks traditionally performed by pathologists may very well be in jeopardy. In such a setting, other specialties (especially subspecialties) are likely to fill the void. This is likely to be catalyzed by the emergence of the new resource-based relative-value scale. Subspecialties in medicine and surgery will be looking for additional ways to retain income when they cannot expect as much for their services as before. This scenario is especially worrisome given the necessity for the practice of pathology to expand into the domain of molecular biology. Unless problems causing the shortage in pathology manpower are addressed, not only are our traditional practices threatened, we are also likely to have inadequate manpower to take advantage of those areas crucial for the future of pathology.

Recruitment of pathology trainees. Recent trends from the 1989 Association of Pathology Chairmen's Survey of first-year pathology residents.

The evolving pathology manpower shortage requires that we examine recruitment issues closely. We present data from the 1989 Association of Pathology Chairmen residents' questionnaire and analyze the most important recruitment patterns. Of 685 first-year pathology residents in 1989, 451 (66%) responded to the survey. When compared with other specialties, 1989 pathology residents are older (mean age, 30.1 years), more frequently women (38%), more often foreign medical graduates (23%), and more commonly have MD/PhD degrees (7.8%). Among pathology residents, the fifth year of required training is the most important negative factor in choosing pathology. Over 50% of 1989 first-year pathology residents changed their mind about another specialty to enter pathology; 37% chose pathology only after graduating from medical school. In 1988 and 1989, 63% of first-year pathology residents responding to the Association of Pathology Chairmen residents' questionnaire indicated that role models were an important factor in their specialty choice. The most typical role model was a male pathologist, approximately 47 to 48 years old. Role model influence tended to be greater for those residents who decided to enter pathology earlier in medical school. Nevertheless, over 50% of those residents who decided to enter pathology after medical school claimed that role model influence was important in their choice. Role models remain a valuable resource for improved recruitment into pathology.

DNA content and proliferative index in cutaneous squamous cell carcinoma and keratoacanthoma.

The histologic separation of keratoacanthomas (KA) and well-differentiated squamous cell carcinoma (WDSCC) using established criteria may present a diagnostic dilemma in the individual case. The authors questioned whether the DNA index (DI) and/or the proliferative index (PI), as shown by flow cytometry (FCM) might assist in this differential diagnosis. Thirty-six well-differentiated squamous cell lesions of skin were independently classified as either WDSCC or KA by a panel of three pathologists. Six poorly differentiated squamous cell carcinomas (PDSCC) also were included in this study. Sections from paraffin blocks were prepared by standard techniques and analyzed by FCM. Mean DI values were: KA 0.96%, WDSCC 0.99%, and PDSCC 0.88%. The differences in the mean DIs were not statistically significant. Mean PI values were as follows: KA 16.7%, WDSCC 14.8%, and PDSCC 20.2%. Differences were not statistically significant. The authors conclude that the FCM measurements of DI and PI do not help in separating KA and WDSCC of skin.

Recruitment of pathology residents: APC questionnaire results, 1987 and 1988.

Our data show a persistent decline of US graduates entering pathology. Moreover, our data indicated that the NRMP provides only a small percentage of the total pathology slots ultimately filled. If the intentions of the 1988 cohort remain consistent, the predictions of Anderson et al concerning a shortage of community-hospital and private-laboratory pathologists seem to be well-founded. This evidence, coupled with the long-acknowledged shortage of academic pathologists, makes improved recruitment an imperative. Recent reports have described several potentially important recruitment tools. However, substantial change in recruitment needs to take place if significant shortages are to be avoided.

Intracardiac myxomas: twenty-year echocardiographic experience with review of the literature.

We reviewed the echocardiograms of 35 patients with intracardiac myxomas. Patient data were combined from two geographically distant laboratories. No significant variations in the patient profiles were encountered. Most patients were white (33 of 35) with a mean age of 45 years. The diagnosis was suspected on clinical grounds alone in only six of 35 patients before the echocardiogram was done. M-mode recordings were the primary echocardiographic modality available in the first 16 patients, whereas two-dimensional studies were also done in the others. Continuous and pulsed wave Doppler echocardiography were added in eight of the most recent studies. In one patient color flow imaging from both transthoracic and esophageal approaches was possible to better visualize a large left atrial tumor. Thirty-three patients had solitary tumors (29 left atrial, three right atrial, and one left ventricular), and two had multiple tumors. The most characteristic finding, as expected, was the demonstration of abnormal mass echoes produced by the myxoma tissue. Several interesting features not previously emphasized in the literature included abnormal notching of the interventricular septum and posterior left ventricular wall probably produced by displacement from the larger mobile left atrial tumors dropping into the mitral sleeve. This was best appreciated by the M-mode recordings. In one patient with an associated atrial septal defect, movement of the tumor into the defect appeared to alter the expected downward displacement into the mitral orifice. In the patients who were studied by two-dimensional, Doppler, or color flow imaging, tumor movement was evidenced by abnormal frequency shifts, and dispersion of flow around the tumor mass was readily appreciated. Surgical removal was performed in all patients. Follow-up echocardiograms were done postoperatively ranging up to 17 years. Recurrent tumors occurred in two patients, both of whom had congenital myxomas. Echocardiography is proving to be an unparalleled tool in the diagnosis of intracardiac tumors.

Plasma cell dyscrasias.

In this article we have discussed the usefulness and limitations of the bone marrow examination in the differential diagnosis of the plasma cell dyscrasias. Because of the overlapping clinical and morphologic features encountered with these disorders and problems due to random marrow sampling, the difficulties in making a correct bone marrow interpretation may be quite formidable. The applicability of immunohistochemistry has been discussed and the need for clinical correlation emphasized.

The recruitment of pathology residents: a 1987 conference report on challenges and responses.

There is general agreement within pathology that there is a serious problem in the recruitment of US medical graduates into the field. Basic to this decline is inadequate exposure of medical students to the pathologist as a physician who is important to the care of patients and open to a range of clinical and research opportunities unparalleled in other medical specialties. Programs designed to increase the familiarity of students with pathology, both within the curriculum and outside of it, beginning before medical school and extending after medical school, have been proposed to reverse the downtrend in recruitment. Changes in the basic structure of pathology training programs, which would shorten the time commitment, are also considered important in increasing the attractiveness of a pathology career.