A lump -- a hard lump about the size of a small egg -- on the right side of my groin next to my leg. My amateur diagnosis: a hernia, even though I've never had a hernia and this lump doesn't hurt. It doesn't cause me any discomfort at all. It's just, well, there.

Could be a hernia, my physician agreed, but it could be something else, like lymph nodes acting up. Better see a surgeon.

The surgeon examined the lump carefully, first while standing then lying down -- me, not the surgeon -- all the while asking a series of questions. I don't think it's a hernia, he said, but let's get a CAT scan and take a look.

The night before the CAT scan I was watching "Jeopardy" with Sam the wonder black Labrador Retriever, who likes to watch with his head in my lap so I can scratch behind his ears. I'm a believer in dogs' uncanny ability to detect illnesses or disorders, so I asked Sam if he noticed anything unusual about me. His only response was the familiar muffled snort which lets me know he knew the correct question to the last "Jeopardy" answer.

Back to the surgeon for another conference. The CAT scan determined that we're not dealing with a hernia. I need to do a needle biopsy, the surgeon said, so we can send a sample from the lump to a pathologist for diagnosis. "Needle biopsy" sounded kind of nasty, but necessary, of course. Could be one of a thousand things, the surgeon said. Better not to start with all the might bes, could bes. I agreed.

The surgeon performed the needle biopsy Tuesday and pronounced it a success. We should hear from the pathologist by early next week. The only drawback, the surgeon cautioned, might be that the pathologist will need a larger sample. If that's the case, the surgeon will have to go back in and remove a lymph node or at least more of the lump. Ouch! For now, we'll assume the needle biopsy produced a sufficient sample.

That night I was reading the paper while Sam rested his head in the familiar spot on my lap. Hmmmm, I thought, there's an incision where I had the needle biopsy today. Even though it's covered with gauze and a bandage, maybe Sam might be able to detect something now.

Sam, I asked, is there anything different about me tonight? Is there anything going on inside me that you need to warn me about?

Sam sat up abruptly and had one of those serious Lab expressions on his face. What is it, boy? What's wrong? What are you trying to tell me?

Arrf, woof, ruff.

Oh, sure, it's time for "Cash Cab." Paw me the remote.

(Anyone who thinks I'm taking this lump too lightly, you're wrong. With my physician, surgeon, pathologist -- and Sam -- we'll find out what's going on.)