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torie
11-18-2009, 01:11 PM
Some woman on another board keeps insisting that one of the risks of chemo is a high risk of cancer caused by the chemo. This doesn't make much sense to me, she's not providing any cites, and it's just fishy. So I went googling, and couldn't find anything to link later cancer to chemo, other than some badly written site that didn't provide any cites for it's claims.

Is there any reputable science that suggests that later cancers can be linked to the cure, or is this just 'alternative medicine' mumbo-jumbo?

Dahnlor
11-18-2009, 01:17 PM
Well, chemotherapy is extremely abusive to the body in general, not only to the cancer it is intended to treat. While I have no qualifications or statistics, it's not outside of the realm of possibility that it could cause things not to work properly elsewhere. Whether that's a different cancer or just losing your hair, I imagine that those risks are inferior to allowing the original cancer to run its course.

D

Philster
11-18-2009, 02:06 PM
"Topoisomerase inhibitors are drugs that get in the way of the enzymes called topoisomerases. These enzymes work to separate the DNA strands to be copied. These drugs are used to treat certain forms of leukemia, lung cancer, ovarian cancer, gastrointestinal cancer, and others. And this drug has two groups; type I and type II. However, some of the inhibitors can cause a secondary cancer called myelogenous leukemia, and this can be seen 2-3 years after the drug has been taken."

from http://www.chemotherapyfacts.com/types-of-chemotherapy-drugs.html

Pray for peace
11-18-2009, 04:06 PM
Survivors of childhood cancer are at a greater risk for development of second malignant neoplasms later in life, in part due to use of chemotherapy agents in treating the childhood cancer. Cite. (http://www.cancer.gov/cancertopics/pdq/treatment/lateeffects/HealthProfessional/page4)

Several large studies have examined the incidence and spectrum of second malignant neoplasms (SMNs) in childhood cancer survivors, in whom the cumulative risk at 20 years posttreatment varies from 3% to 10% and is three to 20 times greater than that expected in the general population. The magnitude of risk and the type of second cancers substantially differ according to the primary malignancy; the type, dose, and combinations of therapy received; and the presence of genetic predispositions. ... Alkylating agents, platinums, and topoisomerase II inhibitors are associated with the development of leukemia.[2-13] Epipodophyllotoxins are known to increase the risk for secondary leukemia, and anthracyclines may also increase this risk after treatment for solid tumors.[14] The more commonly reported second cancers in childhood cancer survivors are breast, thyroid and bone cancers, and therapy-related myelodysplasia and acute myeloid leukemia (t-MDS/AML). T-MDS/AML has been associated with specific chemotherapeutic agents, such as alkylating agents and topoisomerase II inhibitors.[3,6] A dose-dependent relationship is noted with alkylating agents, which typically cause t-MDS/AML after latencies of 5 to 10 years. Cytogenetic abnormalities in the alkylating agent-associated t-MDS/AML characteristically involve chromosomes 5 or 7. T-MDS/AML associated with exposure to topoisomerase II inhibitors classically has a shorter latency, no preceding dysplastic phase, and cytogenetic abnormalities involving chromosome 11q23. While the risk of solid tumors continues to climb with increasing follow-up, the risk for t-MDS/AML plateaus after 5 to 10 years.

Marley23
11-18-2009, 04:32 PM
Radiation and chemotherapy can cause cancers. When you already have cancer, a potential future side effect is not as much of a major concern.

cerberus
11-18-2009, 06:32 PM
It's a necessary evil: fight the current cancer, or prevent secondary cancers by being dead via the initial cancers.

Smeghead
11-18-2009, 06:57 PM
There's also the fact that tumors often secrete factors that inhibit the growth of any other secondary tumors out there. When the primary tumor is removed, that sometimes allows other small tumors to start growing.

Manda JO
11-18-2009, 06:58 PM
My husband had non-Hodgkin's lymphoma in the late 70s when he was 7. My impression is that treatment was extremely aggressive (they did not pussy-foot around with cancer in the late 70s--they figured he was dead anyway, so throw everything at it--surgery, chemo, and radiation). Is there anything he should do because of the increased risk? We don't even really know the details of his treatment--he was a small child then, and his mother is dead. We always dutifully tell the doctor that he had cancer in the past, but they are fairly meh about it.