Fundamentals of Cancer Therapy

0
16

[ad_1]

Treatment of cancer as a whole evolves from surgical oncology through radiation oncology and through medical oncology. Now it is the era of biological oncology. The future oncologist may not be a surgeon or a gist who manipulates the cells in the laboratory and then do the extension of treatment. That is the way the systems go. I am very happy to see that Ayurveda is coming up with plans to establish a medical oncology. Allopathy, Ayurveda and Homeo systems of medicine are not competitors, however those who can do best for a patient, should be able to execute the specialty whatever it may be.

Here are few areas, where we have thoroughly failed in management, like hepato-cellular carcinomas, pancreatic tumors, etc. I think these are the areas where the thrust should be given to all the incoming branches of medicines. In central part of Kerala, hepato-cellular carcinoma, pancreatic tumor etc are very common. The allopathic medicine cannot offer them much relief so they send them to palliative clinics. These are the areas where, other systems of medicines should be able to come up and try to do some thing. But all the experiments should be on scientific basics.

I am starting with some examples (case reports). A girl with acute lymphoblastic leukemia was treated in 1991-92, after treatment; she got married & is now well settled in Dubai. Unlike many other chronic diseases cancer patients can go back to their normal life after treatment. Another case, a lady with acute myeloid leukemia after treatment returned back to the normal life. There is another story of a mother, who had an acute lymphoblastic leukemia, when she was pregnant. The patient was not willing for an abortion and to take the medicines. The pregnancy continued & only chemotherapy was done. The child was born in the oncology ward of RCC & was named as 'Medimon' (because the child was born in the medical oncology ward). The mother & child are now doing well. This is the example of the advancement of oncology where we can select the drugs, which are less toxic.

You should know what cancer is or what actually happens in the body?

Basically in cancer the cells are reasonably immortal. If the cells of the body become immortal, the state of cancer occurs in two ways

1. Uncontrolled multiplication of cells or
2. The cells once attained maturity, but not getting killed.

The natural mechanism of programmed cell death is called Apoptosis. If Apoptosis does not happen, the cells go on multiplying with out any interruption. There will be uncontrolled multiplication of cells, which is the basic problem in a malignancy.

Basics

Let us consider the skin as a model. If injury occurs, there will be a recovery phenomenon. After the repair of the injury, there will be a negative feed back & there is no more repair work that has to be done in a well-balanced state. In malignancy, the cells migrate and they go for an uncontrollable proliferation.

Increased numbers of cells are called hyperplasia, not malignant. But when there is a small change in the nature, (cells doesn't look alike or the arrangement is different), then they are called dysplastic cells. Again, they are not malignant but can progress to a malignancy; but hyperplasia will never progress to a malignancy.

Next we can consider about carcinoma in situ. The cells are showing the features of malignancy, they are still maintained within the basement membrane. When the cells are out of the basement membrane, and shed out, then they are invasive cancer, carcinoma invasive.
Dysplasia can reverse to a normal state also. Once they progress in to carcinoma in situ, they can never reverse. They go for a invasive carcinoma.

Problem is not in the local site alone. The cells remain the state for some times is then multiplies and starts then to migration.

Ways of migration:

1. Invasion of the blood vessels or lymphatic – migration
2. Spread by other routes like CSF, implantation and trans coelomic spread.

Terminology:

Cancer is not a single disease. With lot of etiologies and characters cancer exists. That's the problem in identifying the plan of action of cancers. Cancers can occur in anywhere on the body including hair follicles. No area, sex, age, is excluded. Depending of the type of tumors terminology varies. (Lymphoma on the lymph nodes, sarcoma on the connective tissues etc.) The epithelial tumors are called carcinoma; connective tissue tumors are called sarcoma.

Cancers detection & diagnosis:

No patient should be seen or treated as cancers only with a histopathological diagnosis.
Basic diagnosis criteria, including fine needle aspiration, biopsy, operative specimen on which we are doing histopathological study etc should be there. But the pathologists should give in black & white, and say that this is a malignancy before you enter into treatment. This should be done in all cases, except in brain tumor, where tumor is in a very vulnerable site. In there cases, you are justified in treating with out a biopsy, but we should have evidence on radiology to say that there is a tumor which is malignant. There are many non-malignant tumors which may mimic malignancy has to be excluded before you treat them as a malignancy.

Features of malignancy.

Normal cells, if any variation in size and shape, you can describe them in two ways.

1. The benign tumors are described as the 'Convert girl appearance' and white or blue & white- Well disciplined going of cells.
2. 2nd type – malignant cells ('College girl appearance' No uniformity) Totally disordered arrangement.

Pathology – Description

1. Morphology- the pattern of cells, low they look like etc.
2. Peoulioe marks- characteristics of certain cells. Eg: – leukemia, where the cytoplasm on the nucleus can be stained using some special stains. Thus they can be easily diagnosed.
3. Immunized chemistry. The cells do expulse antigens, which can be identified with the use of immunized chemistry. Once the cells are identified, we can label them.
4. Cytogenetics: – There are certain cytogenetic abnormalities, which are specific to some tumors. Thus we can identify the type of tumors.

Combination of these tests helps a clinician to arrive at a correct diagnosis.
The pathology, after diagnosing the type of tumors, should predict about the chances of progress of the tumors. The doctor should understand the chances of survival.
The chances of survival depends on

1. General condition of the patient
2. Site of tumors.
3. Grade of tumors (Grade 1 tumors – cells have the features almost like normal cells

Grade 2 tumors – in between the G1 and G2xG3.

Grade 3 and 4 tumors – very poorly differentiated.

They don't have the feature of the primary cells).

As a broad statement, poorly differentiated tumors or fast growing tumors have high chance of metastasis and will respond to the chemotherapy and radiotherapy well. But relapse also will be there. Where as the well differentiated & slowly growing tumors have low chance of metastasis. Their response to chemotherapy & radiotherapy is not much effective.

Tumors.

You should do investigations to understand whether metastasis has happened or not. If metastasis occurred, the prognosis is bad. Before doing all the investigations, you should take the natural history of the diseases & then decide the staging. Natural history is the basic study of the oncology. Tumors have got an affinity to certain areas. In each tumor, there is a specific federacy of metastasis to a specific area. The doctors should know that.

Stage I, Stage II, Stage III, Stage IV ® Stages
Stage I – well localized
Stage II – regional lymph nodes are involved
Stage III – Much more lymph nods are involved
Stage IV – Distort metastasis

TNM classification is the fundamental classification. Idea of ​​cancer detection is to identify the cancer in the 1st stage itself.

Blood tests to diagnose malignancy: –
Tumor markers are certain biochemical products available in the blood, which is secreted by the tumors which when identified, helps in diagnosis .. There is some specificity eg if there is prostate cancers the PSA (Prostate specific antigen) will be high in blood. That doesn't mean that, all patients with PSA will have prostate cancers. But there is one tumor marker, by which we can be sure about the diagnosis in the serum. Beta SEG is detected in the clinical set up in gestational trophoblastic tumors. You can go for treatment without doing the histological test.
What causes cancer: –

Unknown Postulations

1. Heredity
2. Radiations to a certain extend
3. Chemicals
4. Infections

Concept: – cancers do not develop over night; it is a slowly advancing process, which can be reverted at different stages of progression, by intervention. But it can progress if not intervened. Each part has to contribute in the cancer formation.
Molecular aspects: –

Normal cell Gene regulates the cell growth.

When the genes are mutated (in a cancers cell), over activity of the genes (oncogenes) occur. These genes affect the cell growth. The growth is accelerated. Over acceleration of the oncogenes is one cause.

Certain genes can prevent the cancers (Anti oncogenes). Balance between the oncogenes and anti oncogenes maintains the correct growth of the cells. Failure of the working of the anti oncogenes leads to over growth of the cells.

What happens at the cellular level: –

You have got receptors in the cells. The growth factor goes and attach to the receptors. Signal, called transudation signals message to the molecules. Getting the genes activated, out put counting from the genes maintain the cycle. The cell multiplies as a result and uncontrolled proliferation occurs.

Doubling process: –

Time taken for a cell to get doubled is the doubling time. Doubling time will be short for rapidly multiplying tumors. If doubling time remains normal, the curve (combustion growth curve) will be linear. But this doesn't happen. The initial part, multiplication will be slow process; but at the end part the multiplication will be fast process. Till a point, ie 109 no of cells are available in the body; it is sub clinical & is not able to detect the cancers grown with any available investigations. By the time, 109 to 1010 no of cell multiplication happen, the patient will be no more.

Importance of early detection in malignancy.

Cancer prevention: –

1. Early displacing cells can have a chance of revision back to normal and we can try to prevent the multiplication process.
2. National cancers convert program (NCKP) In which the thrust be on the tobacco, which is a well established, well-identified cancer causing agent. Even a passive smoker of tobacco has got a 15% higher incidence in developing lung cancers. Smoking in public places should be totally banned.
3. Diet Breast cancers Diet (linked with diet) High fat, high diet- fatty females are the candidates who are more prone to develop breast cancer.

Control measure – Avoid high fatty diets, burn the fat by doing exercises. Vegetables (preferably green leafy vegetables) have anti oxidant property that can reverse the malignant property of the cells. Lot of vegetables should be taken as a part of diet.

[ad_2]

Source by Dr.