It's Time to Start Screening for Bronchogenic Carcinoma:
This page was last updated on May 31,2002. Approximately 154,000 Americans will die this year from bronchogenic carcinoma. There are no immediate hopes that advances in surgical, radiotherapeutic, chemotherapeutic or biological therapies will make any significant reduction in this carnage. Reduction in mortality secondary to prevention of initiation of smoking in children and cessation of smoking are salutory, but any benefits will not be realized for a number of decades. The only hope for any short term reduction in mortality from lung cancer lies in early detection. 
Lung Cancer Screening 2002
There is exciting new information in the area of screening for lung cancer!Claudia Henschke MD has recently published the results of the ELCAP study. Henschke reported that screening with low-dose, non-contrast, spiral computerized tomograms found 27 cases of lung cancer on initial screen in a group of 1000 patients over the age of 60 who had smoked for at least ten years. 82% of cases were Stage I. This critically important study implies that mass screening for lung cancer is now feasible, and offers an opportunity to drastically reduce the mortality from NSCLC. In 1993 Dr. Henschke, of Cornell U. began as principal investigator of the ELCAP trial, a prospective trial to determine the value of low-dose, non-contrast, spiral CT scan in mass screening for early detection of lung cancer. She published the results of this study in Lancet in 1999. Basically, the study showed that 2.7% of screened, asymptomatic subjects, over the age of 60, with at least 10 pack years of smoking and no prior cancer were discovered to have lung cancer in the study. 82% of patients had cancer discovered in Stage IA. This compares to approximately 15-20% of cases discovered in Stage IA and IB in San Gabriel Valley hospitals and 29% discovered in Stage I in the Mayo Lung Study. In the second ELCAP screening examination, one year later, a further 0.7% of patients were found to have a lung cancer, with 88% discovered in Stage IA. This study has created a stir in many medical centers throughout the world. In the Eastern US, many similar screening programs are now being aggressively marketed. The NIH has plans to perform a long-term survival prospective study, but results of such a trial would not be available for a number of years, during which hundreds of thousands of people would die of the disease. Henschke, the Mayo Clinic, British, German, Japanese and Finnish groups are planning prospective trials with an Internet-based collaborative component. Henschke plans to enroll another 10,000 persons in NYC in conjunction with NYU and other local hospitals. You can visit the International Early Lung Cancer Action Project (I-ELCAP) web site for lots more information on this topic or to find a screening program near your home. In my personal opinion, the data from the ELCAP study is so promising that I do not think that it is reasonable to continue a policy of not screening for lung cancer. In the interim before the completion of long-term prospective studies, based upon this best available evidence, my recommendation is that any person who is at increased risk of lung cancer, i.e. smokers, ex-smokers and persons with industrial exposure to asbestos, radium and other known oncogens would benefit from a screening low-dose, non-contrast, spiral CT scan. If insurance entities will not pay for the examination (they almost certainly won't), then it would be a good personal investment. Cornell is currently charging $300 for the study. Another potential source of payment for such screening examinations would be the money from the so-called Master Settlement Agreement between the tobacco industry and the states. This money, perhaps as much as $246 billion over the next 25 years should be spent on tobacco related health issues, like lung cancer screening. The money is currently being grabbed off by politicians and diverted to non-health related political venues. There are potential problems inherent in any screening program. First, many patients will have small pulmonary densities, that are not lung cancers identified on screening CT scans. These densities will require further studies, including possible needle biopsy or surgical resection. 23% of patients screened in the ELCAP study had pumonary densities that required follow-up. =============================================================================Older information: The five year survival without screening of approximately 12-15% in series of patients with lung cancer occurs with depressing regularity in statistics from local hospitals, regional and national statistics in this country and in other nations. Three large U.S. prospective studies have documented 5 year survivals of 32-35% in patients enrolled in programs designed to screen for lung cancer using chest x-rays and or sputum cytology. Despite this very strong suggestive data, a number of large and influential organizations have endorsed an official position that screening for lung cancer is ineffective and not to be recommended. The official position is that, in order to prove effectiveness of screening, a statistically significant reduction in mortality in the entire population screened must be shown in a prospective randomized trial. Historically, this requirement was not met before screening recommendations regarding cervical cancer and breast cancer were implemented. Major controversy continues to involve the interpretation of the results of the largest controlled study of lung cancer in the U.S., the Mayo Lung Project. In this study, approximately 10,000 patients were enrolled in each arm of a prospective randomized study. The control group was given only advice to obtain a yearly chest roentgenogram. The study group recieved chest roentgenograms and sputum cytology examinations every four months during the duration of the study. The five year survival for patients with lung cancer was 40% versus 15% in favor of the screened group, despite that fact that the "advice" group was "contaminated" in that approximately 50% of patients had at least one screening CXR during the study. Despite this striking improvement in survival the population mortality in the two groups was not different. This was because there were more cases of lung cancer discovered in the screened group. The explanation given was that various biases had produced the apparent benefit in favor of screening. These biases include lead time bias (cancers are picked up early but they are still going to die, they just die later), length bias and overdiagnosis bias (these are not "real" lung cancers and the patient probably wouldn't have died even if no treatment had been given). To the clinician with significant experience with lung cancer, these explanations ring hollow. The attribution of overdiagnosis bias seems particularly absurd. Significant new data from our colleagues in Japan provides further proof of the effectiveness of mass screening in reduction of lung cancer mortality and addresses the issue of the various types of bias. A prospective study in Japan is not possible because mass screening is a reality there. National laws mandate access to yearly chest roentgenograms in the workplace, and screening programs are also available in schools and regional health clinics. Data on over 3 million patients screened since 1987 has been carefully examined by the Japanese National Lung Cancer Screening Research Group and published in a number of papers. This data confirms the improved 5 year survival (32-56%) in screened patients seen in the National Cancer Institute study in the U.S. and provides strong evidence against the attribution of overdiagnosis and lead time bias. A definitive study is necessary to solve once and for all the effectiveness of mass screening for lung cancer, but in the meantime, the preponderance of evidence is clearly in favor of screening. We should delay no longer. If our representative national professional and governmental agencies are unwilling to advocate screening, then it is up to the initiative of individual practitioners to do so - now.
John McDougal MD One of my patients has written a brief summary of her personal experience with lung cancer and how it has influenced her ideas on screening. Marie Kaplan RN
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