Debulking is the surgical removal of part of a malignanttumour which cannot be completely excised, so as to enhance the effectiveness of radiation or chemotherapy. It is used only in specific malignancies, as generally partial removal of a tumor is not considered a worthwhile intervention. Ovarian carcinoma and some types of brain tumor are debulked prior to commencing radio- or chemotherapy. It may also be used in the case of slow growth tumors to shift tumor cells from phase of cell cycle to replicative pool.
It is usually a long and often complicated procedure taking several hours or more to perform, depending on internal involvement and location.
Debulking is also known as cytoreduction surgery; "cytoreduction" refers to reducing the number of cancer cells.