Sarcoidosis: Patients receive reassurance that the radiographic abnormality is not neoplastic in origin and the security of a verified diagnosis.
Tuberculosis: Primary TB is most often self-limited; progressive pulmonary disease or extension to the cervical lymphatics will evolve in fewer than 5%; miliary disease and meningitis are less frequent sequelae in adults than children. TB limited to the mediastinum is relatively noncontagious as most patients are sputum smear-negative. Early ascertainment will lead to treatment, forestalling progression (and later reactivation); but, under a policy of vigilant observation, advance will become evident; and outcome should not be adversely affected by therapeutic postponement.
Hodgkins Disease: Approximately 90% of individuals with stage IIA HD are cured by radiotherapy and/or chemotherapy. The effect of delayed diagnosis on curability is not known; presumably, it would lead to the conditions of some patients being diagnosed at a more advanced stage. The long-term survival in stage IIB is 85%, while that of stage IV is 65 to 75%. If all cases of stage IIA HD progressed under observation to stage IV, survival would decline from 90 to 65% and there would be one additional death from HD for every four cases, which, to prevent, would require that 4X3,600=14,400 persons with ABHL undergo mediastinoscopy.
Non-Hodgkins Lymphoma: Delay in diagnosis would not be expected to impact survival in patients with low-grade NHL who are unlikely to be cured with any therapy. In aggressive NHL, the likelihood of cure in persons with stage I-II disease and favorable prognostic factors is 84%; if delayed diagnosis permitted progression to stage III-IV, survival would fall to 43%. Assuming that all cases of NHL in the 20- to 40-year-old age group are aggressive and that all progressed to advanced stages under observation, there would be one excess death for every 2.4 cases, which, to prevent, would require that 2.4X33,000=79,200 persons with ABHL undergo mediastinoscopy.
Combining the figures for all lymphomas reveals that 12,200 mediastinoscopies, at a cost of $37 million, would be required to prevent one excess death from either HD or NHL; a procedural mortality of 0.01% would offset this gain.