What is Metastasis?

5 facts about Metastasis.

1. Definition
A tumor is said to have metastasized when it spreads from its primary site, to other nearby or distant parts of the body, via blood , lymph, etc.

2. What is the mechanism?
The tumor cells detach from the primary tumor, and enter the bloodstream via the process of angiogenesis, or spread via lymphatics.This mainly happens because the malignant cells possess certain properties, like an improper intracellular cementing substance.

the mechanism of metastasis via blood

What are Benign Tumors ?

5 facts about Benign Tumors

1. Definition
Benign tumor is a cell mass that does not have an invasive potential or the capacity to spread.

2. Characteristics

• they show a limited growth. 
• the cells are not anaplasitc. They still resemble the parent cells and have not undergone complete dis-figuration.
• the cells divide more than normal cells do, but this process slows down and stops in a certain amount of time.
• these cells are always confined in a capsule or fibrous tissue, which has a distinctive border and shape.
• these cells lack the ability to spread to neighboring tissues.

a benign tumor in the fibrous capsule

What is Malignancy?

7 facts about Malignancy

1. Definition
Malignancy is a life-threatening progressive condition.Malignant Cancer means unwanted, uncontrolled growth of cells which are structurally and functionally different from their parent cells.

2. What goes wrong?
The DNA present in the nucleus of all the cells in the body is the source of 'genetic-control' over the structure and function of each cell. When, due to some reason, the DNA is repeatedly damaged, it might undergo mutation (change) and and that 'genetic-control' is lost. Hence, the cells start dividing in a haphazard manner, only to produce more abnormal cells. This abnormal cell mass is what we call 'tumor'. It has the potential to damage to the surrounding tissues and organs, creating a 'micro-environment' of its own.

3. Proto-oncogenes and Tumor-suppressor genes.

 G1, S, M, G2 are the phases of a cell cycle which are regulated by the genes, mutation of which causes formation of tumor.

30 common terminologies in Oncology

These are some of the most commonly encountered terminologies in the realm of Oncology.

MALIGNANCY- a condition that is progressive and life-threatening. Malignant Cancer means unwanted and uncontrolled growth of cells destroying the surrounding tissues and having the potential to spread.

BENIGN- non malignant growth which is localized.

NEOPLASM- new-growth of cells that may be benign or malignant

TUMOR- a collection of cells that forms a lump or swelling

5 reasons why you should study Oncology

1.IMPORTANCE
Lets consider a usual 'there's a new disease breakout' scenario.When a disease is in the limelight for affecting many people all over the world, or some part of the world (or even just a few celebrities!), a lot of importance is given to that particular one. It's like an impending doom over all...There are a host of people researching all of a sudden,  new medications coming out every other day, and it stays in the news for quite sometime, atleast as long as the media's short-lived memory lasts! Then a very promising cure is found, and people die no more.
Well, this applies to a lot of diseases that have come and gone, which then seemed deadly, but eventually proved to be otherwise,for example, small pox, or polio. However, this does not apply to Cancer, and a few other diseases like AIDS. Cancer has beaten 'em all and stayed for decades, and it hasn't become any kinder. Allow my personification of Cancer, it helps me relate to it better. Cancer's like this cruel king who's been ruling over the 'health' of millions ever since it came into existence. Swift as a cat, it selects random, completely harmless, quite normal beings, and the next thing they know is their world's upside down! It leaves grieving families behind, if at all 'leaves' them completely...

Cancer and people.

Gone are those days when doctors were the only people who knew about diseases.This statement is true not only for simple flu, but also for complex cancer.In the present time, diseases exist beyond the big fat medicine books. With all the knowledge explosion on us by media, all the awareness campaigns by the governments, people are more than just aware of the diseases that exist for real. But all of this awareness and knowledge, does it really have a role to play? Are we, the so called city-people, considering getting ourselves screened and checked regularly? No. unless ofcourse we have visible symptoms which are hampering our lives.

Mastectomy | early and late complications

Complications of Mastectomy
Various complications can arise during or following the procedure of Radical Mastectomy. These can be categorized as early complications or late complications.

Early complications:

•  In our previous article, we saw that while operating, the nerves and veins around the breast have to be carefully preserved. So, the first complication that arises would be while operation, if the nerves and veins are injured. Injury to nerves of serratus anterior and lattisimus dorsi can take place. Cephalic or axillary veins can also be damaged affecting the circulation in and around the breast and increasing the chances of developing 'post-operative edema'
•  Chances of having an infection post-op are high if there's some amount of collection.
•  Because of the collection of fluid, there may be tension in the sutures.
•  If suturing is done under tension then sloughing of skin may occur.

Late complications:

• First of all, there can be a chance of local recurrence of cancer in the same area.
• There can be recurrence around the previous site, like in the axillla.
• There can be formation of distant metastases, like in the opposite breast.
• Difficulty with shoulder movements can be experienced.

edema seen in the right arm

Mastectomy | Types of Surgeries

What are the types of Mastectomy surgeries?
In the previous post, we learnt various aspects about Radical Mastectomy, like the structures that are removed, and are preserved, etc.Now, we will learn more about other modifications of Mastectomy which are the more extensive surgeries and the less extensive ones.

• The more extensive surgeries

1. Biopsy of the internal mammary node 
While performing the radical mastectomy, sometimes a biopsy can be taken from the internal mammary node which lies behind the 2nd intercostal space (between the two ribs)
This is done for the purpose of a better diagnosis and to know the extent of spread of cancer.

These are the Lymph nodes around the Breast

What is Mastectomy?

Introduction to Mastectomy
Mastectomy is a surgical procedure that involves removal of  the breast along with a few structures around the breast.

Why is Mastectomy performed?

• Curative purpose: in case of breast cancer or malignant tumor of breast.
• Preventive purpose: Prevention of breast cancer in high risk individuals

What are the structures removed ?
it includes en bloc or total removal of

• the entire breast mass, with the tumor
• an elliptical flap of skin is removed, whose center corresponds to the center of the tumor
• areola and nipple always removed
• lymph nodes in the axilla
• fat tissue below the skin all around the breast is removed
• pectoralis major muscle removed with its covering or fascia
• pectoralis minor muscle removed with its covering
• superficial fibres and covering of external intercostal muscle,upper rectus abdominis,serratus anterior,subscapularis,latissimus dorsi.

mastectomy

Oncology Today | BRCA1 gene

What happens when BRCA1 gene is mutated? 
The diagram below depicts the beginning of mutation.

BRCA1 mutation

Oncology Today | Angelina's Choice

Angelina's Choice.

The old adage “an ounce of prevention is worth a pound of cure” certainly came alive with this great example of actor/director Angelina Jolie who recently got a double mastectomy done as a preventive measure, as she found out that she had the 'faulty gene' for breast and ovarian cancer. Well, you may think 'a double mastectomy' isn't an 'ounce' of prevention ! But it is. There are a million 'ordinary' women out there facing the same dilemma and they choose not to get this surgery done because of numerous reasons. I'm sure one of them is the whole idea of losing both breasts even before something went wrong! Being a lady myself I understand a little about how this can affect a woman in all the realms of her life. But this bold and wise step taken by Angelina Jolie is a message to all that says, 'life is more precious than one's body image , and life is too short to wait for something to happen before we act' Angelina is an actress, and her body image is surely way more important to her than maybe ours is to us. And yet she chose to take this step, which i'm sure will start a 'trend' and many women out there will not mind giving this a thought.

Here's the original article in Angelina's own words, 'My Medical Choice' as given in New York Times.

''MY MOTHER fought cancer for almost a decade and died at 56. She held out long enough to meet the first of her grandchildren and to hold them in her arms. But my other children will never have the chance to know her and experience how loving and gracious she was.

Brachytherapy | Prostate Cancer

How is  Brachytherapy used  for Prostate cancer?

• In prostate cancer, Brachytherapy is given using Radioactive 'seed implants'
• 'Seed implants' are  small metallic seeds of the size of rice grains
• These seeds are placed in the tumor using general anesthesia or spinal (epidural) anesthesia
• These seed implants give small doses of Radioactivity
• This is usually done on an out patient basis 
• This effect spreads a few millimeters around the seeds
• It's effect fades away in a years time

seed implants

How is Brachytherapy for Prostate cancer  given ?

Brachytherapy | Side effects

What are the side effects of Brachytherapy?

Acute side effects:

• At the site - bleeding, bruising, swelling, discharge, discomfort are common.
• They last for a few days and resolve.
• Fatigue is experienced like in all other RT techniques.
• In case of skin cancer, desquamation (scaling) and ulceration maybe seen.
• In case of prostate or cervical cancer, bowel and bladder complications are seen.
• for example, urinary retention, incontinence (loss of control over bladder), dysuria (painful urination),etc.
• Diarrhoea, increased frequency of bowel movements, constipation, minor rectal bleeding can be experienced.
• Can be managed medically.

Dry desquamation of skin

Brachytherapy | Step-wise Procedure

What is the step wise procedure of administering Brachytherapy?
In the previous article about brachytherapy, we learnt about the basics of it.Now, lets talk in detail about the procedure of brachytherapy.

• Thorough clinical examination of the patient is done.

• Investigative procedures like X Rays, Ultrasonography,CT scan, MRI are carried out.

• Shape, size, location, etc of the tumor are determined.

• Position of 'source applicators' (applicators without the radioactive source) is decided and placed in situ using image guidance by X rays, ultrasonography, CTscan, MRI, etc.

• Images of patient are taken with applicators inside, and fed into a treatment planning software which converts  2 D images into 3 D images.

• Hence, a 'virtual patient' is created.

• Now, 'virtual radiation' is given to the 'virtual patient' to determine the spread of irradiation in terms of its spatial and temporal components.

• This can be seen as 'virtual dose painting'

Virtual dose painting

Brachytherapy | Characteristics and Types

What are the characteristics of Brachytherapy?

• Can be used in combination with external beam radiotherapy and chemotherapy
• Extremely localized effect. The irradiation does not affect  the healthy tissues further away from the source.
• The radiation sources are placed in a protective capsule or a wire, which does not let the source move around, or get dissolved in the body fluids.
• This capsule can be removed later, or allowed to stay permanently.
• It retains its position even if the tumor moves or the patient changes the position.
• It is completed in lesser time than other RT techniques.
• Hence, it reduces the survival of cancer cells.
• This can be given on Out-patient basis, which is convenient for the patients.
• Has shown good patient compliance.

Brachytherapy seed implant (with Iodine-125)
image courtesy-isoaid.com

What is Brachytherapy ?

What is Brachytherapy?
The word 'Brachy' means 'close distance' in Greek.
This is a form of Radiotherapy, where radioactive substance is in very close proximity to the tumor, hence reducing the risk of involving other healthy tissues around.
Also known as internal radiotherapy.
Involves placing a 'short-range radioactive source' either inside the tumor (interstitial), or near the tumor ( intracavitary)

1.Interstitial brachytherapy :

• The radioactive source is placed inside the tumor
• Mainly used for gynecological tumors , breast cancer, head and neck cancers.

Interstitial Brachytherapy

Side effects of Radiation Therapy

What are the side-effects of Radiation Therapy?
It is common knowledge to all by now that mostly all the treatments of Cancer have their share of side effects.
This is true.It's because all the treatments are aimed at 'killing cells' which are cancerous and in this process even the healthy cells are damaged.
These side effects or sequelae, become a hindrance in the life of a Cancer patient.Some of these side effects are seen right after the treatment and vanish eventually, while some of them appear later, and stay for a long time.
In this article, we will discuss about the acute (short term) and chronic (long term) side effects of Radiation therapy.

What are the Acute side effects of Radiation Therapy?
When the tumor is growing inside the body, it develops a micro-environment for itself.And the sudden interruption to the tumor growth process caused by Radiation leads to the following side effects.

Dry desquamation following Radiotherapy.

Radiation Therapy | Combined with Surgery and Chemotherapy

Radiation Therapy is also used as an adjuvant therapy: 
RT is often used in combination with surgery and/or chemotherapy.

a. When combined with surgery:
RT may be given prior to (preoperative), following (postoperative) or during (intraoperative) surgery.

• Preoperative RT was commonly used earlier, but is used lesser now. For example large, borderline resectable tumors, rectal cancer and soft tissue sarcomas

• Postoperative RT is used in many tumors  including tumors of the central nervous system,head and neck, breast,lung, genitourinary, and gastrointestinal tract.RT is given when there are close margins of tumor, residual disease, and lymph node involvement.Disadvantages of postoperative RT are that it may cause delay in therapy until wound healing is complete and reduced blood supply of tissues following surgery.

• Intraoperative RT includes  delivery of a single, large fraction or RT during surgery.This is done with either a treatment machine in the operation theater or by transporting the patient to the RT department during surgery itself.An important benefit of this type of therapy is that normal tissues  can be placed out of the treatment field.For example, small bowel can be conveniently placed outside the RT field.A disadvantage is of this treatment is that only one large dose is given and the benefits of RT given in fractions are not achieved.Although, this treatment has shown remarkable results in retroperitoneal soft tissue sarcoma. Brachytherapy can also be used at the time of surgery. But again, the time for wound healing has to given before other treatments begin.



Radiotherapy with Surgery(intraoperative)
image courtesy-www.radical.com

b. When combined with chemotherapy:

• Chemotherapy may be given before RT (neoadjuvant therapy), during (concomitant therapy) or following RT (maintenance).
• Chemo-radiotherapy has shown to eradicate micrometastasis and improve local control.
• Neoadjuvant chemotherapy has been used in early stage non–Hodgkin’s lymphoma and small cell lung cancer.
• A potential advantage is that the bulky tumor sites can be reduced thus allowing smaller treatment volumes. However, lot of researches suggests that concomitant chemo-radiotherapy is preferable overall.
• For example, this is used in locally advanced cancer of the lung, head and neck,esophagus,bladder, and cervix.

Combination of the two result in various interactions like:

• after radiation, when chemotherapy is given,there is decreased tumor cell repopulation.
• after using both, there is shrinkage of tumor and increased drug delivery to the tumor.
• there is early eradication of tumor cells, hence reducing the chances of the tumor cells becoming resistant to drugs and radiation.
• even if the tumor cells are resistant to one type of therapy, they will be eradicated by the other.
• if the radiation damage is sub-lethal, then chemotherapy prevents the cells from undergoing any sort of repair or recovery.

All three modalities are combined in cases like locally advanced breast cancer, where neoadjuvant chemotherapy is given, followed by surgery and then postoperative RT is given.

Also read 

12 causes of cancer.

What is Radiation oncology?

What are the side-effects of Radiation therapy?

What is Brachytherapy?

Brachytherapy step-wise procedure 

Brachytherapy for prostate cancer.

Radiation Therapy | Uses

What are the clinical applications of Radiation therapy?
Radiation therapy(RT) is used as a treatment alone, or along with other treatments.

1. When Radiation therapy(RT) is used alone:

• Treatment may comprise of external beam therapy alone, brachytherapy alone, or a combination of the two.
• RT is still used in early-stage head and neck as well as gynecologic tumors.
• Only RT or definitive RT  can also give better long-term functional outcome than surgery in some cases.
• Some researches show that  RT can show identical tumor control rates with less long-term side effects compared to radical surgery in women with cervical cancer.
• Another example would be early stage Hodgkin’s disease which is commonly treated with RT.
• We may think that the elderly patients are at higher risk for short term(acute) and long term (chronic) RT  side effects. However,many researchers have shown that age per se is not associated with increased toxicity because of RT.
• It's the comorbidities present in the elderly which may put them at increased risk.
• Hence, RT alone is also a treatment choice in the elderly patients.

2. Prophylaxis or preventive therapy:

• This is done to prevent the spread to cancer in the places where it is likely to happen after the primary site.
• Usually given to regional lymph nodes which are clinically not involved yet.
• An example would be RT  given to liver in case of advanced Hodgkin's disease and pancreatic cancer.

3. Palliation:

Bone metastasis

• As mentioned previously in Radiation Oncology: an introduction, we know that RT is used extensively as a palliative treatment when cure is not possible.It is used for both local and metastasized cancer.
• This has shown pain relief in numerous patients.
• Rapid schedules of RT are indicated for patients with long-bone tumor sites which are not near vital organs.
• Large-field radiation (hemibody irradiation) is indicated for patients with wide spread bone metastasis.
• Whole brain RT is given for patients with cerebral metastasis.
• Palliative RT is also given in case of spinal cord compression,orbital metastases, liver metastases,carcinomatous meningitis, ovarian cancer and locally advanced lung cancer.
• In case of bronchial obstruction, biliary obstruction and esophageal obstructions, Brachytherapy is used for palliative RT.

4. Benign or non cancerous diseases
RT is used in cases of

Keloid treated with RT

• Keloids or over-growing scars
• Hemangiomas or benign tumors of endothelial cells in the blood vessels
• Pterygium or Surfer's eye which is an abnormal growth on the eye
• Desmoids  or tumors arising from fibroblasts which are tendon-like
• Macular degeneration which causes loss of vision
• Heterotrophic bone prophylaxis after arthroplasty
• Renal and cardiac transplant rejection
• Also, for prevention of re-stenosis in patients undergoing coronary angioplasty

Also read 

12 causes of cancer.

What is Radiation oncology?

What are the side-effects of Radiation therapy?

What is Brachytherapy?

Brachytherapy step-wise procedure

Brachytherapy for prostate cancer.

What is Radiation Oncology?

A patient undergoing Radiation therapy

In this introductory article about Radiation Oncology, we will discuss some basics about Radiation therapy(RT) , how it is delivered, what is the purpose of Radiation in cancer , and what kind of damage it causes.

What is Radiation Oncology?

• Radiation oncology is a field that was born shortly after the discovery of x-rays by William Roentgen in 1985
• Used for treatment of malignant (cancerous) and benign (non-cancerous) growths using ionizing radiation.
• Popularly known as Radiation therapy (RT)
• RT has the potential to harm the normal tissues as well, but many significant improvements have been made in the past 2 decades.
• This has improved the targeting of RT due to better imaging techniques and delivery techniques.Normal tissues are spared as far as possible.
• RT plays a major role in Cancer therapy when it comes to cure, and even more in palliation

How is RT delivered?
There are two main types of delivery systems : External beam therapy and Brachytherapy

• External Beam radiation therapy(EBRT)

this is what a linear accelerator looks like

Here, as the name suggests, RT is given through an external device. It is called 'linear accelerator'
The patient is positioned in a suitable manner and RT is given over the tumor area which is marked.

• Brachytherapy

a picture of a patient undergoing brachytherapy successfully

Here, radioactive sources (like needles) are implanted in the body of the patient.
This is done either in the tumor , or near the tumor.

Other special techniques include:

• Stereotactic radiosurgery (SRS)
• Stereotactic radiotherapy (SRT)
• Intensity- modulated radiation therapy (IMRT)

These methods of RT delivery will be discussed in detain in the following articles.
Now, lets find out what RT does to the tumor cells.

What is the purpose of RT?

• DNA present in the nucleus of every cell is responsible of cell multiplication.
• RT disrupts the structure of DNA by breaking the base of DNA molecule.

radiation damage to DNA

What is radiation damage?

• radiation damage is manifested by loss of reproductive capacity of a cell or 'reproductive death'
• most cells do not manifest this until they attempt to divide.
• sometimes, RT induces 'apoptosis' (a process of natural cell death) in the cells which results in their death.
• in case a cell has sustained the damage caused by RT, it divides a couple of times before dying.
• this phenomena of  not expressing radiation damage by cells, is clinically important.
• because of this, the slow dividing tumors may persist for months after RT and appear malignant too.
• a normal report will be obtained only after these cells have had an opportunity to divide.
• eg, in case of prostate carcinoma, a normal biopsy after RT can only be obtained after as long as 24 months.

The clinical aspects of RT are discussed in the next post Radiation Therapy.

Also read
What is tumor staging or TNM staging?
Cancer and surgery.
What are the side-effects of radiation therapy?
Brachytherapy step-wise  procedure 
Brachytherapy for prostate cancer.