1. Cluster Investigations Marie-Anne Sanon, PhD Candidate Steve Hyland, MD Rachel Fischer, MD

2. Case # 1: Cameron Missouri Recent (2008) Total town population: 6,500 Brain Tumor Within 7 months: 12 cases reported August: 68 tumors reported (20- officially confirmed) Vary with age Past residents

3. Case # 1 Cont’ Parties involved:  EPA  DNR  CDC  Missouri Health Department  Community members (town hall meetings) Actions  Level 1: Water, air, soil, samples & environmental testing  Level 2: Further water testing; & Tumor Study

4. Case # 1 Cont’ Findings:  Clusters (cases presented) close to and around the old factories  Levels of arsenic and lead above normal in soil sample around a Rockwool Industry Inc.  Water is safe Outcomes of Findings:  Lawsuits  Further investigations & lead testing  No final conclusion

5. Case # 1 Cont’ Problems/setbacks with this Cluster Investigation:  No report of benign brain tumors  Lack of records  Time vs. need for answers  Cases of past residents valid? (Thun & Sink, 2004, p276)

6. Case # 1 Cont’ http://www.youtube.com/watch?v=rZREkVht1Gc

7. Case # 2: Erin Brockovich

8. Pitfalls of Cluster Investigation Time consuming (i.e. cameron) Requires a lot of resources Rarely confirmed (i.e. cameron) Random due to chance Look nation-wide

9. Pitfalls Cont’ Age & ethnicity Not enough cases Lack of data from health departments (.i.e cameron) No specific statistical analysis method

10. Pitfalls Cont’ Occupational vs. Community investigation Difficulty confiding the temporal & spatial occurrence of clusters Usually done post-hoc and not as a result of prior hypothesis Lack of clinical or molecular tests to determine cause of cancer

11. References Quataert, Armstrong, Berghold, Bianchi, Kelly, Marchi et al (1999). Methodology problems and the role of statistics in cluster response studies: A framework. European Journal of Epidemiology, 15, 821- 831 Thun MJ, Sinks T. (2004). Understanding cancer clusters. CA Cancer J Clin, 54; 272-280. Wartenberg, D (2001). Investigating disease clusters: why, when and how? J.R. Satist. Soc. A., 164 (1), 13-22