According to Wikipedia:

In general, the prognosis of esophageal cancer is quite poor, because most patients present with advanced disease. By the time the first symptoms (such as difficulty swallowing) appear, the disease has already progressed. The overall five-year survival rate (5YSR) in the United States is around 15%, with most people dying within the first year of diagnosis.

According to Connolly:

A few days ago, I learned I joined the ranks of millions of Americans. I have cancer of the esophagus. It was a surprise because, except for some intermittent abdominal aches and pains, I had no symptoms.

So, I’m not a doctor, but it sounds like he’s showing early symptoms, he only has a 15% or living more than 5 years, and he’s more likely than not to die within the next year. But even if you’re right, a 74-year-old, who is undergoing chemotherapy and has a coin-flip chance of survival, is leading one of the most important committees in Congress.

I’m not trying to be cruel to the guy; cancer sucks and it’s awful he’s going through this. But given how narrow the Republican lead is in the House, it’s irresponsible to have him just stay in Congress at all, since he might miss crucial votes. The Oversight Committee is going to be incredibly important for investigating the Trump administration, and having the top Democrat on the panel be a man going through serious health issues is insane.