Prostate cancer in diabetics: Rarer but more aggressive
Prostate cancer: Patients with type 2 diabetes have a worse prognosis
While patients with type 2 diabetes generally have an increased risk of developing cancer, this does not apply to prostate cancer. On the contrary: A number of studies indicate that men with diabetes mellitus are less frequently affected by prostate cancer than men without diabetes.
"Diabetics are less likely to develop prostate cancer, but have a worse prognosis if they are diagnosed with prostate cancer," explains Dr. Pedram Derakhshani, urologist at the West German Prostate Center in Cologne. A current study1 conducted by the University Hospital of Tübingen shows that the survival rate of those affected is reduced if diabetes mellitus is present at the same time as prostate cancer. The scientists found out that patients with type 2 diabetes show lymph node metastases significantly more frequently than patients without diabetes. In addition, the spread and aggressiveness of the tumor is generally higher in men with diabetes, as the results of the study confirm.
HDR afterloading in advanced tumors
"Prostate cancer patients who also suffer from type 2 diabetes pose a particular challenge," emphasizes Dr. Derakhshani. Due to their poorer prognosis, they generally have a higher risk that at the time of diagnosis, tumour protrusions are already outside the prostate capsule," said the urologist from Cologne.
First, the stage and spread of the tumor must be diagnosed precisely. In cooperation with the radiology department of the Clinic am RING, the Cologne specialists use an ultra-high resolution MRI and combine it with an MRI-assisted punch biopsy. If a prostate carcinoma of the medium or high risk group is present, a special form of brachytherapy, the so-called HDR afterloading, achieves the best results with regard to healing rate and side effects2/3.
In HDR afterloading, a highly active radiation source is temporarily inserted into previously implanted needles and irradiates the tumor directly on site. An exact distribution of the radiation dose allows the tumour to be irradiated without damaging surrounding structures such as the bladder, intestines or sphincter. The advantage: "Combined with external radiation, peripheral areas of the prostate and local lymph nodes can also be treated if necessary," explains Dr. Derakhshani. The probability that the tumour will reappear in the prostate area (local recurrence) is therefore lower after combined brachytherapy than after radical surgery.
However, the scientists from Tübingen were only able to clarify the reasons why patients with type 2 diabetes have a worse prognosis. Thus, insulin-dependent signal transmission in prostate carcinoma appears to have changed. This in turn leads to an increased production of proteins that stimulate cell division in the tumour4, but much research is still needed to uncover the exact processes.
1Heni M: Session "Diabetes and Cancer". Annual Meeting of the German, Austrian and Swiss Societies of Hematology and Medical Oncology, 29.9.-3.10.2017, Stuttgart
2Grimm P, Ignace Billiet I, Bostwick D et al. Comparative analysis of prostate-specific antigen free survival outcomes for patients with low, intermediate and high risk prostate cancer treatment by radical therapy. Results from the Prostate Cancer Results Study Group. BJUI 109, Suppl. 1, 22-29, 2012
3Chao MW, Grimm P, Yaxley J et al.: Brachytherapy: state-of-the-art radiotherapy in prostate cancer. BYU Int. 2015 Oct;116 Suppl 3:80-8. doi: 10,1111/bju.13252. Review.
4Heni M1, Hennenlotter J, Scharpf M et al.: Insulin receptor isoforms A and B as well as insulin receptor substrates-1 and -2 are differentially expressed in prostate cancer. PLoS One. 2012;7(12):e50953. doi: 10.1371/journal.pone.0050953. epub 2012 dec 10.