As described by Mr. Chávez and people knowledgeable about his condition, the likelihood is that the Venezuelan president has either stage 2 or stage 3 colon cancer, Dr. Venook said. Stage 2 involves penetration of a tumor through the wall of the colon without spreading to the lymph nodes. Stage 3 involves spreading to the lymph nodes, but not to other organs.
On average, use of chemotherapy in stage 3 improves the likelihood of survival beyond five years to about 70%, from 50% without it, Dr. Venook said.
Chemotherapy is generally of limited benefit in stage 2 disease, but it is sometimes given if a perforation of the colon suggests to doctors that the cancer is at higher risk of reaching the lymph nodes.
Involvement of the lymph nodes compared to no lymph nodes “makes the prognosis appreciably worse,” Dr. Venook said.
When a perforation of the colon is involved, he said, one concern is that the cancer might be disseminated into the abdominal cavity, which would classify it as stage 4. That is the most advanced stage, indicating a spread to other organs and for most patients the five-year survival is 20%.
Certainly the diagnosis of colon cancer matches Chavez’s current predilection for warm-up suits, which hide colostomy bags.