(AREA) -- A grand jury has loaded more charges on a Detroit-area cancer specialist accused of giving unnecessary treatments to patients. Dr. Farid Fata faces 13 additional charges, including fraud, conspiracy to receive kickbacks and fraud during the citizenship process. He's been in custody for six weeks, but a judge will consider lowering his bail at an October 2 hearing. Federal authorities say Fata misdiagnosed patients and ordered unnecessary treatments to enrich himself through Medicare and other insurance programs. The government says one patient who didn't have cancer had 155 chemotherapy treatments. Fata could lose his U.S. citizenship if the government proves he was committing health fraud when he applied in 2008. Fata owned Michigan Hematology Oncology, which has an office in Lapeer.