Authors' objectives:

Veteran Health Administration’s (VHA) Dental Service asked the Technology Assessment Program (TAP) for a review of the literature to identify the level of evidence available as support for use of toluidine blue (TB) as a diagnostic aid within a screening program for oral squamous cell carcinoma (OSCC) in VHA dental clinics. Specifically, VHA’s national cancer strategy (VHA, 2003) requires that screening programs meet evidence standards established by the United States Preventive Services Task Force (USPSTF). USPSTF recommends that a service be provided only where good evidence is available [i.e., “Results from well-designed, well-conducted studies in representative populations that directly assess effects on health outcomes.” (USPSTF, 2004)].

Authors' recommendations: When analyzing the effectiveness of oral cancer screening, TB and other oral cancer diagnostic aids are more notable for their absence than presence in the literature. Systematic reviews generally concur that the evidence base for oral cancer screening, even with the routinely used oral exam, is inadequate to define benefits and harms. Research on diagnostic aids is currently restricted to levels 1 and 2 (i.e., technical efficacy and diagnostic accuracy) in the hierarchy of diagnostic test research detailed on page 3. Therefore, any impact on management decisions and/or patient outcomes remains to be defined. Effective treatment for oral cancer, another core component of screening’s ability to reduce disease-specific mortality, also remains elusive.From VHA’s perspective, large randomized screening trials conducted in India using in-home clinical exams by specially trained primary health care workers certainly fail to meet USPSTF’s representative population study requirement (Subramanian, 2006; Kujan, 2006); test predictive values will be altered by different underlying prevalence of disease and outcomes by differences in health care systems. The largest trial, featured in Kujan, has yet to publish final mortality results, with interim reports relying on surrogate outcome differences in stage distribution for cancers in screening and control groups.Finally, the addition of diagnostic aids to screening programs of uncertain impact is problematic on several levels:“…clinical detection of oral cancer and precancer using toluidine blue dye a.k.a. tolonium chloride (TCl), as an aid should be admitted (to the meta-analysis). The strongest argument against this was that the purpose of using toluidine blue is to disclose whether a suspicious mucosal lesion is likely to be squamous cell carcinoma (SCC). It is thus an aid to oral cancer diagnosis and not an appropriate tool for use in population screening programs in apparently healthy individuals…” Downer (2004).

Project Status: Completed

URL for project: http://www4.va.gov/VATAP/docs/OralCancer2010.pdf

Year Published: 2009

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: United States

Organisation Name: VA Technology Assessment Program

Contact Address: Liz Adams, VA Technology Assessment Program, Office of Patient Care Services (11T), VA Boston Healthcare System Room 4D-142, 150 South Huntington Avenue, Boston, MA 02130 USA Tel: +1 617 278 4469; Fax: +1 617 264 6587;

Contact Name: elizabeth.adams@med.va.gov

Contact Email: elizabeth.adams@med.va.gov

Copyright: VA Technology Assessment Program (VATAP)