Blankfein, who turned 61 last week, explained that late this summer he was "not feeling well" for several weeks and recently had a biopsy. He then learned he had lymphoma, which is cancer of the lymphatic system, or the body's disease-fighting network, according to the Mayo Clinic.
"Fortunately, my form of lymphoma is highly curable and my doctors' and my own expectation is that I will be cured," Blankfein wrote in a note to his colleagues, clients and shareholders.
"My treatment plan will include chemotherapy over the next several months in New York," Blankfein wrote. "My doctors have advised me that during the treatment, I will be able to work substantially as normal, leading the firm. I will, however, reduce some of my previously planned travel during the treatment period."
Dr. Paolo Caimi, oncologist with University Hospitals Seidman Cancer Center and a lymphoma expert, told ABC News that there are several types of lymphoma that can be cured.
"Even though they are aggressive, they can be cured with chemotherapy," Caimi said. "It would not be uncommon for an otherwise healthy patient to working during treatment. In general, we can get lymphoma patients into remission, their treatments are well tolerated and afterwards they have a very high chance of a cure."