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Cancer Chemotherapy

Beta-carotene foods decrease the lung cancers and there’s a couple of studies that don’t really believe that, particularly from over in Sweden and those countries – Finland where the data they have suggests that it really doesn’t help much. The hereditary aspects of colorectal, again, in familial adenomatous polyposis, percent of colon cancers is less than 1% interestingly enough and that’s one that gets a lot of publicity. Chromosome 5Q21 and gene APC are found. In hereditary nonpolyposis you can see the incidence goes up from 1% to 9%. Chromosome is 2Q3P and then it’s chromosome COCA-1 which you probably know about as well as I do.

Prostate cancer is a bigger problem and you’re going to see more and more of that as time goes on. New cases now, 334,000, deaths 42,000. A significant problem that’s getting bigger all the time because we ignored a lot of people who said the screening for prostate cancer, PSA, is of no value and that’s obviously not true. It’s been proven now that it’s been a very significant improvement in our ability to pick up prostate cancer.

The PSA is a glycoprotein. It’s a serine protease lysosomal coagulation and it’s positive in 98% of prostate cancer. There’s very few things that are positive at such a high incidence and so you can see why this has been very helpful. Adjuvant therapy of proven value with breast cancer in the premenopausal and postmenopausal and also Dukes’ C colon cancer.

The adjuvant chemotherapy of proven value in this group include Dukes’ C colon cancer treated with fluorouracil and levamisole and rectal cancers with radiation and fluorouracil.

New chemotherapy agents that you’ll be starting to work with with the oncologists include irinotecan. Cancer uses are fluorouracil resistant colon cancer. Side effect of note is diarrhea. Cladribine is used to treat hairy cell leukemia, beta cell lymphoma and is associated with fever and sepsis. Topotecan is relapsed ovarian cancer where it can be quite effective and it causes diarrhea and dyspnea in some cases.

Now we talk about new chemotherapy agents again, if we look at Taxol or paclitaxel, it works on the microtubules. Its cancer use is ovary, bladder, lung and breast. Side effects are myelosuppression, neurologic symptoms and fatigue. Vinorelbine or Navelbine, microtubule assembly. Lung, breast, myelosuppression and some neuropathy. Gemcitabine is one we’re quite excited about. It causes DNA inhibition but it’s active, although it’s not a lot, it’s definitely active in pancreas. It can cause fever and lethargy and myelosuppression.

I’ll just sum up to point out that gemcitabine, as I mentioned, doesn’t have a very high incidence of helping in these diseases. As you can see, the patients with response rate are usually in the rather low areas but nevertheless when you get a pancreas that goes two years, that’s pretty impressive.

Here’s another group which you can see ovary 22% response rate. Down here at pancreas 11%. But then they do last for a long time.

Non-small cell lung cancer. Paclitaxel and carboplatin are the best agents we feel. 62% objective response which is twice as high as it used to be and duration of response, it used to be about 20 weeks. Now it’s 53 weeks. So we’re doing better.

Here, again, we’re talking about treatment of resistant tumors and that works better with the use of these agents and this particular one is paclitaxel.