Cancer, Tumours, Carcinoma – are they all the same?
Cancer is a word that many people associate with a deadly disease. But what exactly is cancer?
This blog entry is supposed to give you on overview and some insight into cancer. Also, I try to explain all the difficult, sometimes confusing, terminology that comes with it.
Cancer is a malicious (malignant) formation of new tissue (neoplasia). Colloquially, we often speak of tumours. In medical terminology, the word “tumour” means nothing more than “swelling” and is used for malignant as well as good (benign) lumps. As a student, you are advised not to use the word tumour in front of patients early in your education since that is often equated to cancer and may severely unsettle the patients.
The term cancer can probably be traced back all the way to the well-known, Greek physician Hippocrates. He was describing lumps in the chest that did not want to heal. The shape of these swellings reminded him of shellfish with their rotary jars and feet, as they were fished in the harbour of his home island Kos. The Greek word for tumour, karkinoma, and its Latin translation “cancer” are still used today to refer to certain kinds of cancer. But more on this later.
Physicians often speak of oncologic diseases. “Onkos” is the Greek word for lump or swelling. Oncology refers to the teaching about cancer indispositions and oncologists are the doctors who specialise in the diagnosis and treatment of cancer diseases.
How does cancer evolve?
Cancer originates when there are errors in the metabolic cell division in the body. Before cells can divide, they need to copy their genetic material, or DNA, since every cell needs its own set of genetic information. If an error occurs during this copy process, it could entail uncontrolled divisions of the flawed cell and its separation from the bond with its neighbour cells. This new, degenerate cell structure will then expand and spread quickly and aggressively, displacing healthy tissue, infiltrating blood vessels and eventually spreading over the whole body in the form of metastases.
Metastasis loosely translates to “migration” and is an ancient Greek expression. It stands for the migration of cancerous cells into from their origin distant tissue of the body. In this context, one also speaks of daughter swellings. Metastases are created when cells of the original cancerous tissue separate from the tumour, then infiltrate blood or lymph vessels and use their transport to settle in other regions of the body. Feared metastases are, e.g., brain metastases from breast cancer.
Carcinoma arise from superficial skin cells, from mucosa or gland cells. They make up the greatest portion of cancer illnesses – about 90%.
Aside from that, there are so called sarcomas (from the Greek word for meat), that originate in connective tissue (fibroid sarcoma), muscle tissue (myo sarcoma), fat tissue (lipo sarcoma) or bones (osteo sarcoma).
Furthermore, there are neoplasia in the blood and, just to name it briefly, neuroendocrine tumours.
The classification of blood neoplasia is highly complicated and would exceed the limits of this blogpost, therefore I will only give you a quick overview. In general, you distinguish between blood cancer (leukaemia) and lymph nodes cancer (lymphoma). These two kinds can be distinguished into many further subcategories with the help of many criteria and the exact identification is very important for the treatment.
What I hope was conveyed by the preceding paragraphs: cancer is not just one disease but rather a mechanism that produces many different diseases. And there is a huge amount of different kinds of cancer.
With women, the most common cancer is breast cancer (mastocarcinoma), and with men, it is prostate cancer (prostate carcinoma).
Not just the cancers but also the prognoses if a cancer can be successfully treated and how long the patient might have left to live are very diverse.
Not every type of cancer is the same
The number of deaths from breast cancer is dropping significantly since the mid-1990s. This means, continuously fewer women that fall ill with breast cancer die from it.
The five-year survival rate (patients that survive the five years succeeding the diagnosis) for breast cancer patients is currently at 85%.
For all prostate cancer patients, this five-year rate lies at approximately 93%.
A different example, for a cancer with very bad prognosis, is pancreatic cancer (pancreatic carcinoma). This kind is usually detected only very late since it usually causes discomfort only at an advanced stage and additionally this discomfort is unspecific. The five-year rate lies at appr. 8% in Germany.
Steve Jobs, the co-founder of Apple, tragically died of a pancreatic carcinoma in 2011.
The therapy should be planned individually, specific to the kind of cancer, its size, the lymph nodes state, the metastases and so on by an expert.
Principally, the options are surgery, chemotherapy and/or radiation.
Cancer research is one of the disciplines in medicine that is advanced with the highest effort and intensity. This is why cancer could be combatted increasingly well in the last decades through the development of new therapy concepts and the survival rate could continuously climb up. We can hope that the progress made in cancer therapy stays this positive in the future.
Since the therapy varies heavily depending on the kind of the tumour, I do not want to go into further detail at this point here.