Stomach cancer management in Chennai - Are we meeting world standards? - part 1
*This article includes a lot of technical detail. I have never felt that this information should be kept away from the patient.It is also a reflection of the passion by which overcame the challenges of treating gastric cancer in Chennai.
The incidence of stomach cancer in India is less than that of China and Japan, but nevertheless it is one of the highest in the world. We are seeing increasing numbers of patients with stomach cancer in our clinic, but it is very unfortunate that most of the patients have advanced disease at the time of presentation and the treatment options become limited. When I started to see patients with stomach cancer in Chennai, the challenge was to replicate the results of the international surgical standards within the restrictions that exist in health care in India.
The incidence of stomach cancer in India is less than that of China and Japan, but nevertheless it is one of the highest in the world. We are seeing increasing numbers of patients with stomach cancer in our clinic, but it is very unfortunate that most of the patients have advanced disease at the time of presentation and the treatment options become limited. When I started to see patients with stomach cancer in Chennai, the challenge was to replicate the results of the international surgical standards within the restrictions that exist in health care in India.
Today, I would like to discuss only one aspect of the treatment - a surgical technique that evolved into a gold standard in the world - a method called the D2 dissection. When we were in training, I have heard a respected surgeon remarking that D2 surgery for gastric cancer cannot be applicable to patients in India as our patients cannot withstand such a major operation. For a long time, our patients have received a surgery which we now call as the D1 resection.
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| The picture shows Stomach cancer that has spread to the omentum. Cancers of the stomach are advanced at the time of discovery in the patient. Our Challenge is to identify the disease earlier and give a more complete treatment |
Now I will attempt to explain the differences to you. The aim of a "cancer" surgery is "radical" removal of cancer from the body.
Cancer of the stomach spreads in an orderly fashion. For decades, we know how much the cancer spreads along the wall of the stomach. This is the reason we give 5 cm - 8 cm of unstretched stomach as a margin. This will leave 2 options for the surgeon - a total gastrectomy in which the entire stomach is removed and sub total gastrectomy in which part of the stomach is retained.
The second question of "how much" relates to the extent to which the cancer spreads in the lymph nodes surrounding the stomach. There are 2 rings of lymph nodes to the stomach. The first tier is known as the perigastric nodes, simply medical jargon for nodes around the stomach. The second tier lies around the vessels that supply the stomach - the D2 tier. Removal of the second tier of lymph nodes was pioneered by the Japanese. I spent a lot of time in learning and analyzing the work of Maruyama, which was about the spread of cancer in the lymph nodes surrounding the stomach.
I studied the pattern of lymph node spread in our own patients, because there is a gap between the theory of the treatment of gastric cancer and the actual surgical procedure as it is done in Chennai. A lot of my predecessors believe that D2 dissection, which entails removal of the second tier of lymph nodes is prone for complications and our patients cannot withstand the surgery. This challenged my own learning and experience and I sought to answer them. I did not have the sophisticated instruments that Kitagawa and colleagues use in the current lymph node studies. So I devised simple dye injections to study the pattern.
We studied about 22 patients using 2 different techniques. One of the key information that we got is that the second tier of lymph nodes is involved in 20% of the patients. Now, our data was not adequate to see who actually had this type of spread. This is a large percentage and the denotes the possibility of missing cancer in 1 in 5 patients, if the second tier of lymph nodes is left behind.
That is a tragic news. This is the first challenge we had in our hands.
The second most important factor in surgery is safety. When I attempted the D2 dissection, this was the most important concern. But over these 2 years, I have come to see that these patients are no different and they do well provided they follow what is a standard perioperative care in our institute.
One of the key failures that I noticed among surgeons is the reluctance to dissect the 3 key vessels of the stomach to remove the lymph nodes. The ability to do so requires experience in pancreatic and bile duct cancer surgeries, which our group could translate to the D2 dissection.
To reproduce Maruyama's meticulous methods required attention to detail. We started in 2009 by recording the details of the branching pattern of the major blood vessel to the liver. This is called the Hepatic artery. There are 2 key lymph nodes along the hepatic artery - The node at the terminal end called "the station 12 node" and the more proximal node called "Station 8" lymph node. There are 2 main arterial branches from the hepatic artery - the right gastric artery and the gastroduodenal artery. The study of the anatomical pattern of origin of these vessels allowed us to dissect and separate the hepatic artery and remove the lymph nodes and bare the entire vessel. This allowed us to harvest the Station 12 and the Station 8 entirely. And it gave access to the main vessel of the stomach - the celiac axis.
The second challenge was to dissect and clear the key perioesophageal lymph node stations - designated 1 and 3 by Maruyama.
I would continue the story in Part 2.
Cancer of the stomach spreads in an orderly fashion. For decades, we know how much the cancer spreads along the wall of the stomach. This is the reason we give 5 cm - 8 cm of unstretched stomach as a margin. This will leave 2 options for the surgeon - a total gastrectomy in which the entire stomach is removed and sub total gastrectomy in which part of the stomach is retained.
The second question of "how much" relates to the extent to which the cancer spreads in the lymph nodes surrounding the stomach. There are 2 rings of lymph nodes to the stomach. The first tier is known as the perigastric nodes, simply medical jargon for nodes around the stomach. The second tier lies around the vessels that supply the stomach - the D2 tier. Removal of the second tier of lymph nodes was pioneered by the Japanese. I spent a lot of time in learning and analyzing the work of Maruyama, which was about the spread of cancer in the lymph nodes surrounding the stomach.
I studied the pattern of lymph node spread in our own patients, because there is a gap between the theory of the treatment of gastric cancer and the actual surgical procedure as it is done in Chennai. A lot of my predecessors believe that D2 dissection, which entails removal of the second tier of lymph nodes is prone for complications and our patients cannot withstand the surgery. This challenged my own learning and experience and I sought to answer them. I did not have the sophisticated instruments that Kitagawa and colleagues use in the current lymph node studies. So I devised simple dye injections to study the pattern.
We studied about 22 patients using 2 different techniques. One of the key information that we got is that the second tier of lymph nodes is involved in 20% of the patients. Now, our data was not adequate to see who actually had this type of spread. This is a large percentage and the denotes the possibility of missing cancer in 1 in 5 patients, if the second tier of lymph nodes is left behind.
That is a tragic news. This is the first challenge we had in our hands.
The second most important factor in surgery is safety. When I attempted the D2 dissection, this was the most important concern. But over these 2 years, I have come to see that these patients are no different and they do well provided they follow what is a standard perioperative care in our institute.
One of the key failures that I noticed among surgeons is the reluctance to dissect the 3 key vessels of the stomach to remove the lymph nodes. The ability to do so requires experience in pancreatic and bile duct cancer surgeries, which our group could translate to the D2 dissection.
To reproduce Maruyama's meticulous methods required attention to detail. We started in 2009 by recording the details of the branching pattern of the major blood vessel to the liver. This is called the Hepatic artery. There are 2 key lymph nodes along the hepatic artery - The node at the terminal end called "the station 12 node" and the more proximal node called "Station 8" lymph node. There are 2 main arterial branches from the hepatic artery - the right gastric artery and the gastroduodenal artery. The study of the anatomical pattern of origin of these vessels allowed us to dissect and separate the hepatic artery and remove the lymph nodes and bare the entire vessel. This allowed us to harvest the Station 12 and the Station 8 entirely. And it gave access to the main vessel of the stomach - the celiac axis.
The second challenge was to dissect and clear the key perioesophageal lymph node stations - designated 1 and 3 by Maruyama.
I would continue the story in Part 2.
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