Chemotherapy, also called chemo, may come in different stages for different cancers. For those like lymphoma and leukemia, chemo comes right after the diagnosis, as there is no surgery involved. For cancers that involve tumors – carcinomas and sarcomas – chemo typically comes after the surgery, as a preventive measure.
However, in cases where a tumor may be too big to operate, chemo may be recommended before surgery to shrink the tumor. Depending also on the stage of cancer, chemo may not be recommended at all.
The stages of cancer are determined by a detailed pathology of the tumor, obtained during surgery. The lab looks at different factors of the sample:
- Irregularity in shape of dividing cells
- Large variably shaped nuclei
- Variation in cell size and shape
- Loss of normal specialized cell features
- Poorly defined tumor boundary
- Grade – differentiation
- Tumor markers
- Level of invasion (lymphatics and blood vessels)
- Gene mutation
To determine all these factors requires specialized tests on the sample of the tumor tissue and takes some time. The multitude of factors that the pathologist is looking to determine the stage of cancer and its level of aggressiveness.
In general, cancer advancement is divided into four stages, which then are also graded by letters. We will only consider general stages as this would go beyond the broad scope of this blog.
Stage 1 is the earliest stage marked by only local involvement and usually the small size of the tumor. This is the stage where for some cancers, chemo may not be highly recommended.
Stage 2 means that the cancer is locally advanced, and the tumor is larger than in stage 1. Cancer might have also spread to some nearby lymph nodes.
Stage 3 involves locally advanced cancerous tumors that have spread to more lymph nodes. It may also have its margins extended into the tissue surrounding the tumor.
Stage 4 involves the spread of primary cancer to distant areas of the body. These are called metastasis. For instance, a breast or prostate cancer in its advanced stage typically likes to spread to lungs or bones. We then say that the primary breast/prostate cancer metastasized to lung/bone, as opposed to lung or bone cancer that when primary, are completely different kinds of cancer. Stage four cancer is regarded by the medical world as terminal cancer.
So depending of the type and stage of cancer that you may have, your oncologist will recommend the appropriate treatment: chemotherapy or perhaps if you are lucky, recommend skipping it.
It is worth knowing that there are several systemic chemotherapies:
- Traditional chemo, which hits the whole body indiscriminately. It kills the good and bad cells equally.
- Hormonal chemotherapy for those cancers that are hormone-dependent (most common are breast and prostate).
- Then there is chemotherapy based on antibodies. These all have their side effects, which we will discuss in upcoming blogs.
Finally, there is a rapidly growing immunotherapy, which is becoming more and more popular these days, as the chemo agents are more and more refined.
Hopefully, we may also witness a rapid paradigm change, with two Nobel Prize winners this year (2018) for their work on human immune cells isolating and killing cancer. It may take time before it comes out of the lab into the mainstream, but perhaps these are the first steps to outdating chemotherapy and its terrible side effects.
Resource website – http://www.chemocare.com/chemotherapy/side-effects/default.aspx