Berlin - German doctors have successfully removed an 18-kilogram cancerous tumour from a Saudi woman patient, leaving her weighing only 37 kilograms as she goes into rehabilitation.

Capital Health Hospital Group, a Berlin clinic operator, said Thursday it believed the chondrosarcoma, a tumour growing in the bone of the pelvis, was the biggest ever taken from a patient. It had amounted to almost one third of her body weight.

The doctors first shrunk it with chemotherapy, then gradually cut it out in a series of five operations. The woman will now need reconstruction of her pelvis. Her cancer was first diagnosed in Saudi Arabia in 2003.

The mother of three rejected a proposal by Saudi doctors to amputate the right side of her pelvis and her right leg and was instead flown to Berlin where her treatment began last September.

Last summer the tumour was so advanced that she could neither walk nor stand up. In some places the pelvic tumour had burst outwards through her skin. It risked blocking her colon.

Chondrosarcomas are malignant bone cancers that usually begin near the hip joint in adults aged 30 to 50. Long-term survival is closely related to the proportion of malignant cells remaining in the body. (dpa)