Pancreatectomy

The operation required to remove a tumor of the head of the pancreas (“Whipple procedure”) is by far the most technically demanding abdominal operation. The operation required to remove a tumor of the body or the tail of the pancreas is the “distal pancreatectomy”. For these operations to be performed, patients should be free of metastatic disease elsewhere. Unfortunately, almost 95% of such tumors are considered unresectable at the time of diagnosis. Of course they may very well be unresectable when they have already given metastases to the liver or elsewhere, but quite often they are considered unresectable even if they are not really. For example, many surgeons consider these tumors unresectable because they are large in size, they are densely attached to large blood vessels, or because they grow inside the duodenum. We have had a long dedicated experience in surgery of the pancreas and we have developed techniques and strategies with which we can safely remove tumors when considered “unresectable”, or transform initially truly unresectable tumors to resectable. Obviously, these techniques and strategies are not unique to our team, but are implemented to several selected tertiary referral centers around the world with a dedicated interest and a proven track record in pancreatic surgery. The most important and critical aspects in the resection of pancreatic tumors are the following:

1. Wide lymph node dissection. When the total number of lymph nodes removed is lower than 15, the operation is considered oncologically suboptimal and this may predispose the patient to an early tumor recurrence or early development of metastases. In our pancreatectomies we often include 20-25 lymph nodes along with the part of the pancreas we remove. Only then, lymph node dissection can be considered radical. In such a radical lymph node dissection, the bare wall of the portal vein, superior mesenteric vein, superior mesenteric artery, splenic artery, and inferior vena cava are completely visible in the operating field (such as in the photograph to the left). This alone ensures skeletonization of the neighboring vessels, which is an objective proof of how radical and curative the operation has been.

2. Portal vein resection. Portal vein infiltration (invasion/involvement) by tumor is the most common reason that tumors are labelled unresectable. It is true that when this infiltration is wide and involves great length of the vein or encases it, it is indeed unresectable. However, in several cases of portal vein infiltration, we have been able to remove the tumor by removing the involved part of the vein as well, along with the tumor. The resected part of the vein has then been replaced by a graft, which either comes from the same patient, or it may be made of plastic (such as in the photograph to the left). The plan for such a procedure is based on careful study of the CT or the MRI in order to know the exact length of the vessel that is infiltrated, as well as the portion of its perimeter (circumference) involved with tumor.

3. Locally advanced tumor. When the tumor is locally very advanced and infiltrates into larger portions of surrounding vessels and into a wider area around the pancreas (but does not have metastases), it is truly unresectable. In these patients, instead of being nihilistic, we administer neoadjuvant chemotherapy, occasionally associated with radiation therapy. These two regimens may shrink down the tumor (“downstage” it) and convert it to resectable. This way, the tumor “pulls back” from the vessels involved and makes resection possible, usually along with a part of the initially infiltrated vessels.

4. Liver metastasis. Unfortunately, a great percentage of patients with pancreatic cancer have already several metastases to the liver at the time of diagnosis. Such a stage of disease can never be converted to resectable. However, there are very few patients who may have one or two metastatic lesions in the liver. In such patients and provided the resection of the pancreas is straight forward (without portal vein involvement, etc) and the lesions are easily accessible to resection, one may resect these few discrete lesions along with the pancreatic tumor. It can not be overemphasized that such an approach may be appropriate in a very limited and highly selected subgroup of patients.