Dr. Deepak Chhabra
MS. (Bom), DNB, M.R.C.S. (Edin. UK)
- What is cancer
- Cancer Risk factors
- Stages of Cancer
- Early signs of Cancer
- Early detection of Cancer
The world knows this man as a consultant oncosurgeon with vast experience in Gastrointestinal and Hepatobiliary-Pancreatic cancers,who specializes in stapled anastomosis for bowel cancers and sphincter saving resections for rectal cancers. In short, he is the person to be contacted for all kinds of cancer related cases.Richa AgrawalPancreatic Cancer
Thank you Dr Deepak for all you have done for mum, for putting the smile back of her face. I wish you success in all your future endeavors and know that you will continue to touch peoples lives and help them be healthy - the way you have done for my mum….. and me.Nicola MathiasStomach Cancer
For 67years I've led a very healthy life and thank the "Almighty" for it. However as I said all good things come to an end some time and so be it. Out of the blues was detected the dreadful illness "C" which had shown no signs or symptoms whatsoever..... Time had now come for me to choose a very efficient Oncologist for my treatment.Patient
My mother was diagnosed of colon cancer, and I was recommended to see Dr Deepak Chhabra for consultation.Neelu GroverColon Cancer
The first impression of Dr Chhabra was… he is so young! But after consulting him we realized his level of experience and there was a sense of confidence he spilt over us.We knew we could trust him.....
What is GIST?
A gastrointestinal stromal tumor (GIST) is a type of tumor that occurs in the gastrointestinal (GI or digestive) tract, including the esophagus, stomach, gallbladder, liver, small intestine, colon, rectum, and lining of the gut. GISTs are different from other types of gastrointestinal tumors because of the type of tissue in which they start.
Originally, GISTs were thought to be either muscle or nerve tumors, but recent research points to GISTs starting in cells found in the walls of the GI tract, called interstitial cells of Cajal (ICC); these cells send signals to the GI tract to help move food and liquid through the system.
GISTs belong to a group of cancers called soft tissue sarcoma. Soft tissue sarcomas are a group of cancers that develop in the tissues that support and connect the body, and the sarcoma cells resemble the cells that hold the body together, including fat cells, muscles, nerves, tendons, joints, blood vessels, or lymph vessels.
It is important to note that GISTs can be either benign or malignant. Sometimes it may be hard for the doctor to tell immediately whether a GIST is likely to come back after treatment. As a result, the doctor will look at many factors to determine the best treatment, including the size of the tumor, whether it has already spread, how many dividing cells there are, and the tumor’s location.
Because GIST cancers arise from the GI tract wall, they are usually attached to the outside of the involved organ, growing outward; this is sometimes referred to as exophytic. Occasionally a GIST may grow inward through the muscle layer of the GI tract wall and then develop partly inside the digestive tract lumen; this is sometimes called endophytic.
More than half of GISTs start in the stomach. Most of the remaining start in the small intestine, but GISTs can be found anywhere in the GI tract.
How common is GIST?
GIST is one of the not so common tumors Most primary care physicians and many pathologists and oncologists go through their entire professional careers without seeing a single GIST. This is important to patients because misdiagnosis can delay the start of appropriate treatment.
A risk factor is anything that increases a person’s chance of developing a tumor. Although risk factors can influence the development of a tumor, most do not directly cause the disease. Some people with several risk factors never develop a tumor, while others with no known risk factors do.
The majority of GISTs develop for no known reason, called sporadic. There are no known environmental or behavioural risk factors contributing to GIST. Therefore, patients should not worry that their diet or lifestyle choices contributed to GIST.
Random genetic mutations are the apparent cause of GISTs. The majority of GISTs show identified mutations in cell-surface proteins called tyrosine kinase receptors. Most GISTs show mutations in a gene that produces a growth factor receptor called KIT.
However, there are rare examples of GIST running in families due to an inheritable germline mutation. In addition, people affected by neurofibromatosis type 1 (NF1) have an increased chance of developing GIST.
Many patients (mostly those with smaller tumors) have no symptoms.
Larger tumors may cause symptoms that are generally related to the increased mass being accommodated in the abdominal cavity, and such symptoms would not necessarily be different from those other types of tumors.
Symptoms include digestive discomfort, sensations of abdominal fullness, or abdominal pain.
Larger tumors may be detectable as a mass when feeling the abdomen, or as a visible enlargement of the abdomen.
Some patients experience vomiting or diarrhea or intestinal obstruction may occur in some patients.
Sometimes GISTs perforate the stomach or gut lining and bleed into the GI tract, resulting in black or tarry stools, or occasionally in vomiting of blood. Anemia (Low Haemoglobin) may result from chronic bleeding, leading to fatigue. Sometimes anemia may cause the patient’s heart to race (tachycardia). The patient may notice weight loss.
Very rarely a GIST may rupture, making its presence known with a medical emergency.
Though such symptoms are possible, most of them are rather indistinct and merely related to the additional mass that is present in the abdomen. Therefore, many GISTs are found incidentally through medical imaging for other purposes or through surgery for other conditions.
What are the tests carried out to diagnose GIST?
This section lists common tests for the cancers. It is not necessary for all the tests to be performed for a patient. Your doctor will select the tests that will assist him / her to have the maximum information about the tumor/ disease. Before referring you for tests, your doctor will take a full medical history and examine you. You may also have a blood test and chest x-ray to check your general health.
Computerised tomography (CT) scan
A CT scan is a type of x-ray that gives a picture of organs and other structures (including any tumours) in your body. It is used to see more details of a cancer and its relation to the surrounding organs in your body. It also gives information related to cancer spread into the lymph nodes, liver or lungs.
Endoscopy / Gastroscopy
In this test, a thin, flexible ‘telescope’ (called an endoscope) will be passed down your throat so that the doctor can examine your oesophagus, stomach and the upper part of your bowel. If anything unusual is seen, the doctor can put instruments down the endoscope and remove tissue to examine under a microscope (biopsy).
Endoscopic ultrasound scan (EUS)
This is similar to having an endoscopy and may be occasionally for people who may have stomach GIST. For this test, the endoscope has a small ultrasound probe on the end for more detailed information about the local spread of the tumor. It can help the doctor decide whether you should have some other modality of treatment before surgery.
Positron emission tomography (PET) scan
This test is combined with a CT scan by injecting a radioactive material in the body to highlight all areas where the tumor has or can spread. This test may be used to build up more information after an MRI or CT scan. PET-CT scan is not necessary for all patients. Your doctor will decide if you need to undergo this scan.
A biopsy is diagnosis made under a microscope by a pathologist using a small bit of tissue removed from a suspicious area or lump that is found to be abnormal.
Gastrointestinal stromal tumor (GIST) is a cancer that may be suspected from its appearance in imaging techniques such as CT scans, but the diagnosis can only be determined by a pathologist after examining tumor tissue from a biopsy, or from the entire tumor after it has been surgically removed (resected). The main role of the pathologist is to determine the type of tumor (diagnosis). This is done by judging the characteristics of tumor cells viewed under a microscope and the results from a series of tests. The pathologist also gives an opinion regarding the prognosis (the risk of recurrence or metastasis).
The pathologist selects and applies immunohistochemical tests (IHC studies) to tumor samples. These tests involve using antibodies to detect the presence of proteins that are expressed by the tumor cells. The pattern of proteins that are present or missing in a respective tumor in conjunction with the morphology of the tissue is taken into account for the final diagnosis.
The best immunostaining method for identifying GIST is to test for expression of KIT, also called CD117. Therefore, a positive result for KIT antibody testing is a strong indication of a GIST diagnosis.
Prior to the introduction of targeted molecular drug therapies (starting with imatinib/Gleevec), surgery was the only useful treatment for GIST. Surgery is still the cornerstone of GIST treatment whenever resection is possible. Complete removal of a primary tumor is potentially curative, especially when the tumor is small and the risk classification is low.
What is the treatment of GIST?
Many years of treating patients and testing treatments in clinical trials has helped doctors know what is likely to work for a particular type and stage of tumor. You will be advised on the best treatment for you. This will depend on the type of tumor you have, where it is and how far it has spread and your general health.
Treatment options for people with GIST involve surgery and targerted therapy (Imatinib). Chemotherapy and radiation therapy have no role in treatment of GISTs.
Surgery is the main treatment for a gastrointestinal stromal tumor (GIST) that hasn’t spread is usually surgery. The goal of the surgery is to completely remove all of the cancer.
No matter what type of surgery is done, it is very important that it is done carefully by a surgeon with experience treating GISTs. GISTs are thought to be delicate tumors, and many doctors have voiced their concerns about bleeding and the possible increased risk of spreading the cancer if the capsule around the tumor is opened during surgery.
Targeted therapy is a treatment that targets specific genes, proteins, or the tissue environment that contributes to cancer growth and survival. In 2002, the U.S. Food and Drug Administration (FDA) approved imatinib (Gleevec) for the treatment of GIST. Imatinib is a tyrosine kinase inhibitor, and it is the drug of choice in treating GIST. Since this drug has become available, the prognosis for patients with GIST has improved considerably. It is usually given as either the only treatment or in combination with surgery (before or after surgery).
The usual dose of imatinib is 400 milligrams (mg) daily. In some patients the dose can be raised to 800 mg daily.
Sunitinib (Sutent), like imatinib, is a tyrosine kinase inhibitor called an anti-angiogenic that stops tumors from creating new blood vessels. It was approved in 2006 by the FDA for treating GIST when the tumor continues to grow even after treatment with imatinib, or when imatinib cannot be given.
If you are found suitable for the surgery, you will be usually admitted one or two days prior to the proposed date of surgery. There may be dietary restrictions and you may be given laxatives to evacuate your bowels prior to surgery. Your blood group will be checked and blood is usually reserved for all major abdominal surgeries.
It is always a good idea to start with deep breathing exercises once you are admitted to the hospital. Your doctor may summon a physiotherapist to assist you with the same. You will have most of your body parts shaved for the surgery. You will be given a consent form for your signature.
The form would have details of the procedure to be performed on you by your treating surgeon. In case you have any doubts you should feel free to ask them to the surgical team.
The surgeries for pancreatic cancers depend on the location of the tumor in the pancreas.
Majority of the pancreas cancer however are in the head region of the pancreas and the operation performed is “Whipple’s surgery”.
“Distal Pancreatectomy” is performed for tumors located in the tail or body portion of the pancreas and the surgery involves removal of the body and tail portion of the pancreas along with the spleen.
This major operation involves removal of:
- part of the pancreas
- part of the first part of the small bowel (duodenum)
- part of the stomach
- part of the gall bladder and part of the bile duct.
The diagram below shows what your surgeon removes
The surgeon reconnects the remainder of the pancreas, bile duct and stomach to different sections of the small bowel so the digestive tract keeps working.
A feeding tube may be placed during the surgery to replenish nutrition to the patient after surgery.
This operation is performed for certain types of pancreatic tumors located in the tail or body portion of the pancreas. This surgery involves removal of only the tail of the pancreas or the tail and a portion of the body of the pancreas. The spleen is usually removed as well.
Sometimes surgery may begin with the hope it will cure the patient, but the surgeon discovers this is not possible. In this case, the surgeon may continue the operation as a palliative / bypass procedure to relieve or prevent symptoms.
Cancers growing in the head of the pancreas can block the common bile duct as it passes through this part of the pancreas. This may cause pain and digestive problems because the bile can’t get into the intestine and patient develops jaundice and vomiting. The bile chemicals will build up in the body
There are 2 options for relieving bile duct blockage.
Surgery can be done to reroute the flow of bile from the common bile duct directly into the small intestine, bypassing the pancreas. Sometimes, the stomach connection to the duodenum (the first part of the small intestine) is rerouted at this time as well. Often, late in the course of pancreatic cancer, the duodenum becomes blocked by cancer, which can cause pain and vomiting that requires surgery. Bypassing the duodenum before this happens can help avoid a second operation.
A second approach to relieving a blocked bile duct does not involve surgery. Instead, a stent (small tube) is placed in the duct to keep it open. This is usually done through an endoscope (a long, flexible tube) while the patient is sedated. The doctor passes the endoscope down the patient’s throat and all the way into the small intestine. The doctor can then insert the stent into the bile duct through the endoscope. The stent helps keep the bile duct open and resists compression from the surrounding cancer.
Drinking and eating after surgery.
After an anaesthetic, the movement of the bowel slows down and usually takes about 72 hours to get back to normal. After about 48-72 hours you will probably be ready to start taking small sips of water, however your doctors will tell you when it is appropriate for you to start drinking some fluids. This will be gradually increased after a couple of days until you are able to eat a light diet.
You will probably be ready to go home in about 10-14 days after your operation and once your stitches have been removed. If deemed appropriate your doctor may send you home with stitches and call you later to remove the stitches. By and large you should be able to climb several flights of stairs after your discharge from the hospital and you will be given diet instructions.
Before you leave hospital you will be given an appointment for a post-operative check-up at the outpatient clinic.
Diet after pancreas surgery.
You will be transferred to the Intensive care unit after the surgery. Your recovery will depend on the magnitude of surgery performed. After the operation, the patient is usually monitored in the ICU for 48 to 72 hrs and the overall hospital stay (if no complications) is usually between 10–14 days.
Your pain and discomfort will be taken care of by the anaesthetic team. You will be given pain-killers and an intravenous infusion (drip) to replace your body’s fluids until you are able to drink and eat again after a few days. You will also have a naso-gastric (NG) tube in place.
This is a thin tube that passes down your nose into your stomach or small intestine and allows any fluids to be removed so that you don’t feel sick. It is usually taken out within 48 hours. Sometimes a small tube (catheter) is put into the bladder to drain your urine into a collecting bag.
After your operation you will be encouraged to start moving about as soon as possible. This is an essential part of your recovery. If you have to stay in bed the nurses will encourage you to do regular leg movements and deep breathing exercises. You will be seen by a physiotherapist who can help you to do the exercises.
At first, even tiny meals may make you feel uncomfortably full. You will need to eat very small amounts very often at first. Then, gradually increase the amounts and then the time between meals. At first, you may find you need to eat every hour or so in order to get enough nutrition.
There is no restriction on the type of food you eat after a pancreas surgery and you should be able to eat all that you did before surgery. Fizzy drinks can make you feel full – it is probably best not to drink with meals at all, as any liquid will fill you up.
Try keeping a food diary if you are having problems you think are related to your diet. Take a small notebook and draw a line down the centre of each page. Write down what you eat and when on the left of the page. Write down any symptoms you get and when on the other side of the page. After a few days, you may be able to spot which foods cause which symptoms.
Some people need to take tablets to help digest fat and proteins, and some people develop diabetes, which may require treatment.