Lloyd Morgan's Column

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Commentary on the Final Report of the RMIT Cancer Cases

Introduction

This report is a cover-up of the first order. I will restrict my commentary to the cases of brain tumor on Levels 16 and 17.

There were 4 brain tumors reported in a population of 114 staff members in an 11 year period. These tumors were:

• One glioblastoma multiforme
• Two meningiomas
• One haemangioblastoma
• One pituitary adenoma

The report remarks that since there was only a single malignant tumour, "the presence of a single case only of a primary malignant brain tumour within the population on these floor levels does not enable an accurate epidemiological analysis." This statement was made in the context that no "benign" brain tumour data is collected in Victoria. The report also states that a pituitary tumour is not a brain tumour stating that the World Health Organization (WHO) classifies such a tumour as "an endocrine tumour and not a brain tumour."

There was neither an attempt to examine the incidence rate of "benign" brain tumour beyond Victoria nor was their statement correct about WHO's classification of pituitary tumours. Pituitary tumors^[1] are classified by WHO and here in the United States as a brain tumour.

Let's examine the facts for each of these brain tumours using data published by the Central Brain Tumor Registry of the United States (www.cbtrus.org).

• The age adjusted rate of glioblastoma is 3.05 per 100,000 people per year
• The age adjusted rate of meningioma is 4.53 per 100,000 people per year
• The age adjusted rate of haemangioblastoma is 0.9 per 100,000 per year
• The age adjusted rate of pituitary adenoma is 0.92 per 100,000 per year

There were 114 staff members over a period of 11 years. Thus the person-years of this cohort are 1,254. Using the above incidence rates the number of each tumor type that would be expected is:

• Expected glioblastomas are 0.038. The observed/expected ratio is 26.
• Expected meningiomas are 0.11. The observed/expected ratio is 8.8
• Expected haemangioblastomas are 0.011. The observed/expected ratio is 89.
• Expected pituitary adenomas are 0.012. The observed/expected ratio is 87.

This report is a cover up of the first order.

[1] The pituitary gland is located inside the cranium at the base of the brain. Meningiomas are classified as brain tumours in Victoria. These are tumours of the meninges, the lining of the brain and the spinal cord. Pituitary tumours are beneath the meninges.