Sunday, October 19, 2008

Screening tests

I have three times been tempted into having myself screened for serious disease. It seems like a sensible and prudent thing to do as one gets older, since, for the most part, early diagnosis means early treatment and early treatment carries with it a greater chance of cure.

Screening as an important plank in Public Health policy. Ideally a screening test should be for a serious and important disease. It should be a disease that is cured by early treatment, but dangerous if diagnosis is delayed. The test should pick up all the cases of the disease but not show up positive if the disease is absent. Finally the test should be affordable.

The first time I tested myself it was for prostrate cancer. The PSA test is cheap enough and misses very few cases, but unfortunately it shows up positive when the prostate is enlarged from whatever cause. I was one of those ensnared by a false positive. When this occurs the only thing to do is a prostatic biopsy.

A prostatic biopsy is done without anesthetic. I plastic probe is inserted into the rectum and a spring-loaded knife shoots out through the rectal wall into the prostate to take the biopsy. Only it isn't one biopsy; it's ten. It doesn't hurt, unless it happens to hit a nerve. Imagine that it hits a nerve on biopsy number two; you have eight more to imagine as you wince and sweat with the pain. That's what happened to me. Luckily the biopsy was benign, but as you wait several days for the result you envision bony secondaries and early death before your misery is relieved.

Serum cholesterol is high in populations with a high rate of heart disease. If you have high blood pressure and a high cholesterol, it seems a reasonable thing to take things further, since the risk of a heart attack might be averted by judicious diet, or even angioplasty. This was especially so because we had introduced CT angiograms that did not require catherization. An intravenous injection of radio-dye followed by a CT of the heart will demonstrate that the coronary arteries are patent. Unless there is calcification. Because one of my coronaries had a plaque of calcium in it, it was not possible to say whether it was patent or not. After all I had to have a standard angiogram. I tried not to think about the risk of heart attack or stroke as the cardiologist threaded his wire up my arm and into my heart. In truth, this is a painless procedure and for me the result was encouraging. I was put on statins just like nearly everybody else of my age and my choldesterol is now low-normal.

For ten years I administered chemotherapy to patients with colon cancer. Often I felt that there ought to be a screening test for this disease. About half the people diagnosed with colon cancer die from it, but early surgery is curative. Unfortunately the only screening test that picks up all the cases is colonoscopy, which is a skilled procedure in which a flexible telescope is inserted into the rectum and passed all the way round the colon until it reaches the appendix. This is a very long way, and the procedure takes at least half an hour.

Because an aunt recently had surgery for colon cancer, and two of my grandparents died from it, and because of my experience in treating the disease I thought I should have a colonoscopy, which took place a month ago. The procedure itself may or not be painful; I can't remember because they inject you with midazolam which doesn't send you to sleep, but you forget everything that happened. If the procedure is not unpleasant, the preparation is. The day before they give you a liquid that flushes everything out of your bowel; not a pleasant procedure and quite painful.

Unfortunately, my colonoscopy was not normal. The cecal wall was rather rigid and there were superficial ulcers. These were biopsied. I was sent for a CT scan the next day, and the radiologist found a small lymph node. The biopsies came back normal, but they thought that the lymph node looked like carcinoid. Carcinoid is a slow growing tumor that often starts in the appendix. It produces a hormone, serotonin, that causes flushing, diarrhea and asthma. It is only slow growing; it sounds nasty, but it is better than having carcinoma. I had a 24 hour urine collection for 5-HIAA, which was normal, and a radioactive octreotide scan. Octreotide is an antidote to serotonin that binds to it. After an injection of the octreotide, I had to lie under a gamma camera for two hours on three separate days. The scan was negative, but on hearing this the surgeon seemed to be resigned to the fact that I had cancer, and cancer that had spread to the lymph nodes at that. He booked me in for surgery for next Tuesday, likely to be followed by chemotherapy. As I remember my statistics, the five year survival for Dukes stage C bowel cancer following chemotherapy is about 60%.

This was the first time in my life that I wished I was ignorant of medicine. Happy are those whose physicians look them in the eye and say, "My dear, I am going to look after you. Trust me."

I knew too much. Well do they say a coward dies a thousand deaths. I had a day of pure funk. For the first time I felt like a patient. After a day I settled down. I realized that taking 'anxious thought for the morrow' would not change anything. Many of my friends began to pray for me.

The surgeon decided that first he must take a look for himself (the original colonoscopy had been done by an assistant). Another day of bowel preparation. Ugh! It's not only the effect; the stuff tastes foul. As I was coming out of the influence of the midazolam he told me that all was fine. There was nothing abnormal to be found. The proposed operation was cancelled. I was in the clear! He wondered if I had been taking ibuprofen since they can cause ulcers in the bowel. It's true, I certainly had been following a wrench to my shoulder after falling from a ladder.

But I wonder if there's another explanation. Was it an answer to prayer? It certainly felt like one. Perhaps it was both an answer to prayer and had some physical explanation. Answers to prayer are by their nature incomprehensible.

I have only one word to add. Hallelujah!


Burke said...

I had a colonoscopy last month and was put to sleep. The last thing I remember was the doc coming into the proceedure room and saying hello. The next thing I remember was a nurse gently slapping my face to wake me up. It was the same for my wife about 6 months ago.

The prep the day before was a pain.

Pat said...

Yes. A blessing. As I was reading, my heart literally stopped.....Thank goodness, I continued reading to the end! I was so happy to learn it was an error in dx.

The world needs you for more than another 5 years, Dr. Hamblin.

Anonymous said...

Dear Dr. Hamblin,

We thank God that you are cancer free...


Anonymous said...

In the US colon cancer, breast cancer and prostate cancer are specifically screened for. People who make the effort of seeing their dentists and dermatologists can be screened for oral and dermatologic cancers as well.

screening tests are not perfect and there is always the spectre of "don't ask the question if you don't want to know the answer" which applies to screening if the information gleaned isn't going to be helpful.

PSA testing, eg, is of dubious value in men over 75 yoa...imagine a man who gets the rare but possible sepsis following a prostate biopsy done for an elevated PSA who wouldn't necessarily benefit from treatment for prostate cancer in the first place or the silliness of my 85 yo father-in-law who had such a biopsy (because of an elevated PSA at age 83) and sees his urologist every 3 months, despite (most probably appropriately) refusing any therapy...why does he go and have blood tests every 3 months?

Colonoscopy when done appropriately is a great tool, but not without risk or error. Significant lesions may be missed because of poor colon preparation or observer error (which correlates mainly with the duration and fastidiousness of the examination). Patients may incur complications from the preparation, the conscious sedation, or the procedure (missed lesions, bleeding, perforation).

NSAIDs are well known to cause small intestinal and colonic lesions in addition to the better known gasro-duodenal lesions (ulcers, erosions, etc).

mammograms may miss things or lead to negative biopsies. MRIs are better but not perfect. Whole body CT scans open up too many cans of worms...THERE IS NO FREE LUNCH.


Anonymous said...

Dear Terry,
Enormously glad to hear that you remain healthy.

Hope you will get back to writing your novel. Perhaps you could include a section in it on spontaneous remissions? Just an idea.

It has often puzzled me that there seems to be no in-depth scientific inquiry into such occurrences. I’m told that in the terminal phases of cancers no spontaneous remissions have ever been reported but that they are not unknown at earlier stages.


Terry Hamblin said...

Actually there is a big study into spontaneous remissions that I have on my bookshelf. It is a monograph on teh Conference on Spontaneous regression of Cancer held at Johns Hopkins on May 9-10 1974 and published by the NIH. It starts with a summary by Warren H Cole who collected 176 cases of spontaneous regression from the world literature between 1900 and 1960. The most common examples were kidney (31 cases), neuroblastoma, (29 cases), melanoma (19 cases) and chorioncarcinoma (19 cases). These four types comprised 55% of all regressions. In the same volume Peter Wiernik reports on spontaneous remission of CLL in 12 cases. The remissions lasted from one to more than eleven years.

Anonymous said...

Dear Dr. Hamblin,
I am so glad everything turned out to be ok, thank God. I do not doubt He had a hand in this. You said people were praying for you. You must have prayed too. You are right.. an answer to a prayer is hard to comprehend and it is not always what we expect. Sometimes science and medicine cannot explain those "spontaneous remissions" or cured cases. It is so good to have hope and realize that God is in control. May He bless you and keep you in good health for all the people who need your help.

Anonymous said...

Rejoicing with you over your God-breathed good report! I know you and your family must be relieved. May He continue to bless you with good health and long life.


Anonymous said...

Dr. Hamblin --
have you ever heard of a case when CLL spontaneously regressed or went into remission. Is there a difference between "regress" and "remission"? Have you ever heard of CLL diagnosed by flow cytometry and then, later, the diagnosis turned out to be wrong? Just curious.

Terry Hamblin said...

CLL is like an iceberg 8/9ths is below the surface. The CLL may spontaneously regress in the sense that it is no longer obvious in teh blood, yet still be easily detectable in the bone marrow. Remission is a technical term defined by the CLL Guidelines.

Deb said...

Sorry I didn't see this earlier!I Praise God for your good reports and yes I see prayer as a big hand in this!
God Bless you and keep you Dr. Terry!!We need you and God knows that very well!!
Warm Regards,
Debbie Light

Marcia said...

I also thank God that your surgeon decided to have a look himself!
My story is the other way. My surgeon took more than the sentinel node during breast surgery, just because another node didn't feel right. The sentinel node was clean, but the extra one had breast cancer cells (along with CLL). Further nodes removed were clean, but now I'm looking at chemotherapy for breast cancer.
Do you know of any interaction between chemo for breast cancer and future treatment for CLL?

Terry Hamblin said...

Many of the breast cancer drugs also kill CLL cells, so patients with CLL and breast cancer often find that their leukemia enters remission also.