Prostate cancer: Too much dogma, not enough data

DOGMA 4: SURGERY IS BETTER . . . OR . . .RADIOTHERAPY IS BETTER

One of the tantalizing dogmas of prostate cancer management is the myth that surgery is vastly superior to radiotherapy, or vice versa.

In reality, most of the comparisons of surgery vs radiotherapy constitute comparisons of apples and oranges—surgical staging vs clinical staging, careful case selection, historical comparison, or single-center vs collaborative group outcomes. Once again, few well-constructed randomized trials have attempted to address this question, and most have closed prematurely because of poor accrual. In fact, most clinicians evolve a case-based and intuition-based experience, which is colored to varying extents by their medical school teaching and the medical literature,⁵ and really believe in the dogma and opinions that they quote. When one takes a step back and considers the true long-term outcomes, balancing inaccuracies of definition and documentation of the side effects of treatment,⁶ the variables outlined above, and the heterogeneity of salvage therapy, it is hard to make a strong case that only one therapeutic option reigns supreme.

DOGMA 5: CHEMOTHERAPY NEVER WORKS

Similarly, the view prevailed for many years that cytotoxic chemotherapy had no role in the management of hormone-refractory prostate cancer. With improved clinical staging and assessment, the introduction of serial PSA measurement as a surrogate of response, better definition of the indices of quality of life, and the completion of large randomized trials, it has become clear that the use of chemotherapy improves quality of life,⁷ that survival can be prolonged by the use of cytotoxics drugs,⁸ and that it might even be worth testing the utility of chemotherapy in the adjuvant setting, in combination with hormonal therapy, as is done in locally advanced breast cancer.⁹

EVIDENCE-BASED MEDICINE: THE CURE FOR DOGMA

Ultimately, we have one major tool to help us resolve challenges to dogma, and it is neither rhetoric nor more dogma. Our ultimate weapon is data, and data are best gleaned from well-designed and well-supported randomized clinical trials.

Today, in the United States, fewer than 10% of patients with cancer enter structured clinical trials, reflecting the ennui of government, the medical profession, and patients themselves, as well as the downstream products of disbursement of dogma.¹⁰ As a community we need to address these issues for a broad range of medical conditions beyond cancer by using evidence gained from clinical trials, and by practicing evidence-based medicine.