Germanium sesquioxide, also called Ge-132, is a common dietary supplement that was popularized by the Japanese researcher Kazuhiko Asai, who operated the Organic Germanium Clinic in a suburb of Tokyo throughout the 1970's. He offered the compound to all who came to his clinic, regardless of their illness. This produced many satisfied customers, demonstrating a good safety record for germanium sesquioxide.
In 2000, a group of doctors from the University of Florida College of Medicine and the Veterans Affairs Medical Center reported a remarkable case study of a woman who apparently cured herself of lung cancer with this supplement. The woman was diagnosed with spindle cell carcinoma, a rare form of lung cancer that is highly aggressive. Only 10 percent of patients survive two years after diagnosis even with combined surgery, chemotherapy, and radiation therapy. The woman in the report had a tumor that extended into vital structures, so her doctors considered surgery to be not an option. She had radiation therapy and chemotherapy with etopside/ifosfamide, paclitaxel/cisplatin, mesna, adriamycin, and dacarbazine. Unfortunately, her symptoms continued to get worse, and X-ray images showed continued growth of the tumor.
The patient decided to discontinue therapy, and went on a cruise. There she met a man who claimed that germanium sesquioxide had cured him of lung cancer 15 years earlier. So she took 7.2 g per day of this supplement until she felt her lungs “opening up”, and then tapered down to a low dose. Her doctors followed her for four years, and reported her “clinically and radiographically free of disease” at the time of writing.
The authors report that spontaneous remission would be less likely than a successful response to germanium sesquioxide for this patient. Additional studies in animals have demonstrated anti-cancer effects for organic germanium compounds.
The biggest danger from germanium supplements reported in the literature is kidney damage, which is mostly attributed to contamination by germanium dioxide. I have not found any further reports of success in treating human cancers with germanium sesquioxide.