April 18 (UPI) -- New combination therapy identified that may do more than just extend survival but could cure metastatic prostate cancer.
In recent years, the U.S. Food and Drug Administration has approved six drugs for men with metastatic prostate cancer that increase survival.
Researchers have gone a step further and shown an aggressive combination of systemic therapy or drug treatment combined with local therapy, including surgery and radiation, targeting the primary tumor and metastasis can kill all detectable disease in certain patients with metastatic prostate cancer.
The study, conducted by researchers at Memorial Sloan Kettering Cancer Center in New York City, showed that one-fifth of the 20 patients treated with the combination therapy had no detectable disease, with an undetectable prostate-specific-androgen, or PSA, and normal blood testosterone, 20 months after treatment.
The patients all had metastatic prostate cancer, five with extra-pelvic lymph nodal disease and 15 with bone with or without nodal disease, were treated with androgen deprivation therapy, or ADT, radical surgery that included a retroperitoneal lymph node dissection as needed, and radiation therapy to visible metastatic lesions in bone.
Four of the patients extra-pelvic lymph node involvement, achieved an undetectable PSA after ADT and surgery. The fifth patient needed radiation to achieve the same milestone.
"The sequential use of the three different modalities helped illustrate the role and importance of each in achieving the undetectable PSA with normal testosterone level end point, which represents a 'no-evidence of disease' status," Dr. Howard I. Scher, chief of the Genitourinary Oncology Service at Memorial Sloan Kettering Cancer Center, said in a press release.
Fourteen patients, or 93 percent, reached an undetectable PSA when ADT, surgery and radiation were used.
"A multimodal treatment strategy for patients who present with disease that is beyond the limits of curability by any single modality enables the evaluation of new approaches in order to prioritize large-scale testing in early stages of advanced disease," Scher said. "The end point also shifts the paradigm from palliation to cure."
The study was published in Urology.