Vulvar Cancer Surgery
This procedure eliminates the need to remove large numbers of lymph nodes from both groins in order to determine if the vulvar cancer has spread to these lymph nodes. The whole concept of this operation lies in the discovery of the first node (i.e., sentinel node) to drain a vulvar cancer.
Before surgery using local anesthesia a safe radioactive substance is injected along the perimeter of the vulvar cancer in the nuclear medicine suite of the hospital. Then a patient is taken to the operating room and placed under general anesthesia and a blue dye is injected also along the perimeter of the cancer. By using a radioactivity detection device and visual inspection for a blue lymph node, the sentinel node is detected and removed through a small incision. Although there can be more than one sentinel node there are typically no more than 2 or 3 at the most.
The sentinel is sent to the pathologist to determine if cancer is present. If there is no cancer detected, studies have shown that a negative sentinel means that the rest of the lymph nodes in that groin will be uninvolved with cancer and therefore the patient will not need to have all of those nodes removed and will spared the lymphedema that would otherwise develop. Of course, if the pathologist reports that the sentinel is positive for cancer then the gynecologic oncologist will need to perform a full dissection of the lymph nodes in groin. For vulvar cancers that are off the midline of the body (i.e., not too close to the center of the vaginal opening), a sentinel lymph node biopsy is only necessary on the involved side, and not on both sides.
The goal of radical surgery for vulvar cancer is similar to that of cervical cancer which is to obtain a clear, cancer-free margin around the tumor. Most often this can be performed without having to remove the entire vulva which includes the labia majora on both sides along with the labia minora, clitoris, underlying subcutaneous tissues, and perineal body above the anus.
Vulvar cancers that are not close to the center of the vaginal opening can be removed successfully with a 2 cm surgical margin around the cancer, thus sparing any disfiguring surgery on the other side of the vulva. Although not very common, very large cancers of the vulva may require a more extensive operation to obtain clear margins and for this reason the gynecologic oncologist may consider using other methods (e.g., chemotherapy and or radiation therapy) to shrink the cancer so that a less extensive operation can be performed.