A recent peer review of a landmark clinical study published earlier this year in the longest running medical journal, "The Lancet", strengthens the case for hyperthermia as a powerful therapy for rectal cancer. In the United States alone there are over 130 thousand new cases of colorectal cancer each year, and 43% of colorectal patients will die from the disease.

Support for colorectal hyperthermia is behind commercial efforts of BSD Medical Corporation for the BSD-2000 deep regional hyperthermia system. General acceptance of hyperthermia as a prescribed treatment for rectal cancer would create a demand for many hyperthermia treatment systems, as each system has a treatment course capacity to accommodate only about 300 patients per year.

A research team at Charite University Medical School of the Humboldt University in Berlin has reviewed the Dutch Deep Hyperthermia Trials, which were published April 2000 in "The Lancet" (vol. 356, pp. 771-2). The trials reported were a randomized phase III study performed on 358 human volunteers with locally advanced tumors of the bladder, rectum and cervix, and demonstrated the powerful therapeutic effects of hyperthermia in the treatment of certain pelvic cancers. Furthermore, in the case of advanced cervical cancer, the addition of deep hyperthermia (with the BSD-2000) increased the complete response rate from 57% to 83%, and the 3-year overall survival from 27% to 51%.

Now the Berlin group has noted that although the Dutch trials showed "a trend in favor of deep hyperthermia to attain complete tumor response (for rectal cancer)" there were factors in the study that prevented the results from being even stronger. In particular, they pointed out that the population given hyperthermia had a larger mean tumor size and a higher proportion of patients with advanced or metastatic disease than the control group. Jacoba van der Zee, M.D., the lead author for the Dutch study, replied to the reviewers, "we fully agree with the comments [by the Berlin group] that our study may underestimate the value of additional hyperthermia in rectal cancer." Dr. van der Zee further stated that their paper had omitted the fact that they found hyperthermia added a substantial palliative effect in the patients studied, and lengthened the median duration of palliation from 7 months to 17 months.

The Berlin researchers are currently conducting a phase III trial comparing radiochemotherapy alone with radiochemotherapy combined with deep hyperthermia (using the BSD-2000) in patients with locally advanced non-metastatic rectal cancer. This study could add substantially to the case for hyperthermia in treatment of rectal cancer.