Interleukin 7 and Patient Selection in Immunotherapy for Prostate Cancer

textabstractProstate cancer is a disease of elderly males. An increase in prostate cancer is expected in the coming years due to a growing population of men aged over 60 years of age from 475 million in 2009 to 1.6 billion in the year 2050 worldwide. Moreover, if screening for prostate cancer is taken into account, even more men will be diagnosed with this disease.[1-3] In the early disease stages, prostate cancer is a slow-growing and symptom-free malignancy. Men suffering from prostate cancer are more likely to die of causes unrelated to the condition, such as heart/ circulatory disease, pneumonia, or old age. PIN, prostatic intraepithelial neoplasia, lesions are considered to be a pre-cancereous condition.[4] Once prostate cancer has developed, mostly adenocarcinomas in the peripheral zone of the prostate are observed and different disease stages can be identified. The TNM classification is used to describe the stages of the primary tumor (T), the regional lymph nodes (N), and distant metastases (M). Combining the T, N and M stages for a prostate tumor gives an indication of the extent of the disease (Table 1). At T-stage 1 and 2, the cancer is confined to the prostate. Once the cancer has spread outside the outer layer of the prostate and invades nearby tissues such as bladder and rectum, the cancer is staged at T3 or T4. Metastatic prostate cancer has spread throughout the patient’s body most often to regional or distant lymph nodes (N+) and the bone (M+). At this stage patients often present themselves with the first clinical symptoms which is usually bone pain due to skeletal metastases. As a result of prostate cancer screening, patients are nearly always diagnosed with asymptomatic localized prostate cancer