Maximal Tumor Eradication for Oligometastatic Prostate Cancer

In China, the incidence of prostate cancer is increasing in recent years, and it has ranked 5th among common male tumors and 1st in urinary tumors. Unlike developed countries in Europe and the United States, in China, because prostate-specific antigen (PSA) screening has not been widely popularized, and early prostate cancer is mostly asymptomatic, about 13%-26% of prostate cancer patients have progressed to metastatic hormone-sensitive prostate cancer (mHSPC) at the time of initial diagnosis. Compared with localized prostate cancer, the 5-year survival rate of mHSPC is only 29.3%, which is prone to symptoms such as bone pain, pathological fracture, hematuria, and dysuria and seriously decrease the survival and quality of life. As a result, it is of great significance to carry out more refined management of mHSPC, explore more scientific treatment options, and delay the time to CRPC, which is of great significance for improving the prognosis and quality of life of patients and reducing medical burden. However, there is still no standard treatment strategy for OMPC patients which need more clinical exploration. Treatment of prostate primary in oligometastatic prostate cancer (OMPC) may improve survival and do not significantly increase complications. Radiotherapy showed excellent therapeutic effects on metastatic lesions, prolonged survival and without increasing significant adverse effects. In 2019, The New England Journal of Medicine reported a TITAN study that combining apatamide with ADT for metastatic hormone-sensitive prostate cancer, which significantly reduced the risk of death (82.4% VS 72.5%, P=0.005), and improved progression-free survival (68.2% VS 47.5, P \<0.001) without increasing adverse effects of treatment. In 2020, Johns Hopkins University published a phase I clinical study of radical treatment of 12 cases of OMPC. Patients were treated with neoadjuvant docetaxel chemotherapy or abiraterone, combined with radical prostatectomy for primary lesions, and stereotactic radiation for bone metastases to achieve the purpose of complete tumor eradication. Preliminary results showed that no additional complications were found except neutropenic fever in two cases. At the same time, the proportion of PSA maintained undetectable in 1,2,3 years was 12 / 12 (100%), 10 / 12 (83%) and 8 / 12 (67%), respectively, showing good treatment results. Since 2014, the applicant has rich research experience in the treatment of oligometastatic prostate cancer and our results showed that systemic therapy combined with local tumor reduction therapy can confer a survival benefit for OMPC patients without a significant increase in complications. This clinical trial aimed to analyze the clinical efficacy and safety of maximal tumor eradication strategy for oligometastatic prostate cancer.