Treatment of Indigo—Cancer Relapse
Treatment for Indigo varies per the subtype. Men with Low-Indigo are presumed to have disease confined to the prostate or where the prostate used to be located. Men with Basic-Indigo have a relatively low risk for having micro metastases in the pelvic nodes. Men with fast PSA doubling (<8mo) are at greater risk of having microscopic pelvic node metastases and are High-Indigo.
Low-Indigo is defined by: 1) clear scans, 2) a PSA doubling time over 9 months, 3) if the PSA is rising, it is less than 0.5 after surgery and less than 5.0 after radiation, and 4) the original Stage of Blue prior to initial treatment was Sky, Low-Teal, or Basic-Teal. Men in this category who relapse after radiation might consider observation. Alternatively, some sort of focal salvage treatment can be considered (IMRT, SBRT, proton therapy, focal brachytherapy, cryotherapy, HIFU, electroporation or laser). Alternatively, they can consider intermittent TIP. Men with doubling times over 9 months can consider observation alone without any immediate treatment.
Basic-Indigo is defined as any one of the following, but without any proven disease in the pelvic nodes: 1) a PSA doubling time of greater than 9 months, 2) a rising PSA above 0.5 after surgery or above 5.0 after radiation, or 3) the original Stage of Blue was High-Teal or Azure. Men who had previous surgery are typically treated with IMRT to the prostate fossa and the pelvic lymph nodes along with TIP. Men who underwent previous radiation should receive TIP plus IMRT to the pelvic lymph nodes. Focal treatment with one of the focal options listed for Low-Indigo can be used for persistent disease in the prostate.
High-Indigo is characterized by unequivocal pelvic node metastases and warrants multimodality therapy with long-term TIP (with Zytiga), IMRT to the nodes and, in occasional cases, Taxotere.
ABOUT THE AUTHOR
Mark Scholz, MD is the Executive Director of the Prostate Cancer Research Institute. He is also the Medical Director of Prostate Oncology Specialists Inc. He received his medical degree from Creighton University in Omaha, NE. Dr. Scholz completed his Internal Medicine internship and Medical Oncology fellowship at University of Southern California Medical Center. He is co-author of Invasion of the Prostate Snatchers. He has authored over 20 scientific publications related to the treatment of prostate cancer.