Charles K Chan, MD F.C.C.P.;([unkey...

Charles K Chan, MD F.C.C.P.;([unkeyable]) Carolyn K Wells, M.P.H.;([unkeyable]) Michael J McFarlene, M.D.;(Section) and Alvan R Feinstein, M.D.([unkeyable])

In previous research, we have demonstrated the value of using necropsy "surprise" lung cancer cases, in those in whom lung cancer was not suspected during life, to estimate the size and composition of the "reservoir" of undetect lung cancer in the general population. The popular research was done to determine the characteristics and events of secular changes over time in the composition of the lung cancer "reservoir." The consequence s suggest that further advances in diagnostic technology will enhance detection during life of the large "reservoir" of resectable lung cancer, particularly in women With the increased detection of these reservoir cases during life, the statistical casualty rates for lung cancer will pretend to increase, but survival rates will look to improve because more of the finded cases will be resectable.

For vital statistics onward the occurrence rates and changes in the pattern of disease processe the major sources of data are the death certificates prepared at physicians.[1] These data can be add toed by special surveillance systems of that kind as tumor registries,[2] the vaticinator system,[3] or the Centers for Disease Control[4] Although health statistics derived from these sources have sometimes been criticized as inaccurate, misleading, and unreliable,[5-10] the outcomes are routinely used for structuring health policy, planning health care delivery, and conducting population-based epidemiologic research.

Although necropsy--the greatest in number meticulous method for morphologic identification of many diseases--has been propos as a potentially important epidemiologic tool,[11] its application has been quite limited. The major reason for the limitation is the widespread belief that the necropsy population is a biased demographic sample of the family found in hospitals or in the population at large.[12] An additional clinical bias may arise if patients are selectively chosen for necropsy because of clinical distinctions in their preceding diagnosis and clinical course.

To eliminate or diminish these possible biases, McFarlane et al[13] exhibited a new approach called the "epidemiologic necropsy" In this approach, the potential demographic biases of age and sex are eliminated according to suitably standardizing or adjusting the harsh rates of occurrence from different eras or institutions. Clinical selection bias is reduc according to limiting the analysis to the undiagnosed, unsuspected instances of disease fix in patients who were chosen for necropsy without any previous clinical suspicions about that disease. In like patients, necropsy acts like a screening proces applied to a sample of the general population, that reveals unsuspected cases of disease. Although the actual rates of occurrence for "unsuspected" disease remain uncertain, the findings of McFarlane et al[13] clearly demonstrate the existence of a large "reservoir" of undetect lung cancers. The ends are also consistent with data from the Swedish Cancer Registry.[14-18]

In the now passing study, we wanted to determine by what mode the size and composition of the undetect lung cancer "reservoir" has been affected by way of secular changes in diagnostic technology and "workups." We also wanted to view whether the secular trends of this "reservoir" during the past three decades might proffer any qualitative and quantitative predictions about the epidemiology of lung cancer in the nearest decade.

METHODS

The records of the Autopsy Service of the YNHH were reviewed for a 30-year secular period from Jan 1 1953 [i]or[/i] part of to the other Dec 31, 1982. The necropsy records for all hospital deaths in human frames aged 20 and over were checked for data forward age, gender, and morphologic diagnoses at necropsy Medical-legal cases and patients who were dead-on-arrival at the hospital were exclud from the tabulations because their records were inadequate for determining the premortem clinical diagnoses.

Whenever an instance of primary lung cancer was noted in the necropsy diagnoses, the full protocol--clinical summary, laboratory profile, and postmortem morphologic findings--was examined and categorized according to previously reported classification criteria.[13] Patients whose lung cancer was diagnosed or suspected during life, in succession either a clinical or histologic basis, were classified in the diagnosed assemblage The undiagnosed group consisted of the necropsy surprise patients, whose lung cancer was not suspected during life, and the wrong-primary patients who had been diagnosed during life as having cancer, with the primary site being either unknown or erroneously attributed.

For each necropsy surprise patient, the clinical record was reviewed and a decision made about the apparent cause of death. This clinical decision about cause of death was then compared with what was noted at necropsy In addition, the anatomic extensiveness of each "surprise" case of lung cancer at necropsy was classified according to the TNM connected view of staging.