Lymphadenectomy
Encyclopedia
Lymphadenectomy consists of the surgical removal of one or more groups of lymph nodes. It is almost always performed as part of the surgical management of cancer
.
This is usually done because many types of cancer
have a marked tendency to produce lymph node
metastasis
early on in their natural history. This is particularly true of melanoma
, head and neck cancer
, differentiated thyroid cancer
, breast cancer
, lung cancer
, gastric cancer and colorectal cancer
. Famed British surgeon Sir Berkeley Moynihan once remarked that "the surgery of cancer
is not the surgery of organs; it is the surgery of the lymphatic system".
The better known examples of lymphadenectomy are axillary lymph node dissection for breast cancer
; radical neck dissection for head and neck cancer
and thyroid cancer
; D2 lymphadenectomy for gastric cancer; and total mesorectal excision
for rectal cancer
.
More recently, the concept of sentinel lymph node
mapping has been popularized by Dr. Donald Morton and others. Cancer with various primary sites, breast, melanoma, colorectal, etc., often metastasize early to the first drainage lymphatic basin. This process is predictable anatomically according to the primary site in the organ and the lymphatic channels. The first nodes (sentinel nodes) can be identified by particulate markers such as lymphazurin, methylene blue, India ink and radio-labelled colloid protein particles injected near the tumor site. The draining sentinel node can then be found by the surgeon and excised for verification by the pathologist if tumor cells are present, and often these tumor cells are few and only easily recognized by careful examination or by using techniques such as special stains, i.e. immunohistochemical. When the sentinel node is free of tumor cells, this is highly predictive of freedom from metastasis in the entire lymphatic basin, thus leading to futility of a full node dissection.
The practice of sentinel lymph node mapping has changed the surgical approach in many cancer systems, sparing a formal lymph node dissection for patients with sentinel lymph node negative for tumor and directing a full node dissection for patients with sentinel lymph node positive for tumor metastases. For example in stage II breast carcinoma, using the sentinel lymph node technique, 65% of patients could be spared from a formal node dissection.
Surgical oncology
Surgical oncology is the branch of surgery which focuses on the surgical management of cancer.The specialty of surgical oncology has evolved in steps similar to medical oncology, which grew out of hematology, and radiation oncology, which grew out of radiology...
.
This is usually done because many types of cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
have a marked tendency to produce lymph node
Lymph node
A lymph node is a small ball or an oval-shaped organ of the immune system, distributed widely throughout the body including the armpit and stomach/gut and linked by lymphatic vessels. Lymph nodes are garrisons of B, T, and other immune cells. Lymph nodes are found all through the body, and act as...
metastasis
Metastasis
Metastasis, or metastatic disease , is the spread of a disease from one organ or part to another non-adjacent organ or part. It was previously thought that only malignant tumor cells and infections have the capacity to metastasize; however, this is being reconsidered due to new research...
early on in their natural history. This is particularly true of melanoma
Melanoma
Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye...
, head and neck cancer
Head and neck cancer
Head and neck cancer refers to a group of biologically similar cancers that start in the upper aerodigestive tract, including the lip, oral cavity , nasal cavity , paranasal sinuses, pharynx, and larynx. 90% of head and neck cancers are squamous cell carcinomas , originating from the mucosal lining...
, differentiated thyroid cancer
Thyroid cancer
Thyroid neoplasm is a neoplasm or tumor of the thyroid. It can be a benign tumor such as thyroid adenoma, or it can be a malignant neoplasm , such as papillary, follicular, medullary or anaplastic thyroid cancer. Most patients are 25 to 65 years of age when first diagnosed; women are more affected...
, breast cancer
Breast cancer
Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas...
, lung cancer
Lung cancer
Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...
, gastric cancer and colorectal cancer
Colorectal cancer
Colorectal cancer, commonly known as bowel cancer, is a cancer caused by uncontrolled cell growth , in the colon, rectum, or vermiform appendix. Colorectal cancer is clinically distinct from anal cancer, which affects the anus....
. Famed British surgeon Sir Berkeley Moynihan once remarked that "the surgery of cancer
Surgical oncology
Surgical oncology is the branch of surgery which focuses on the surgical management of cancer.The specialty of surgical oncology has evolved in steps similar to medical oncology, which grew out of hematology, and radiation oncology, which grew out of radiology...
is not the surgery of organs; it is the surgery of the lymphatic system".
The better known examples of lymphadenectomy are axillary lymph node dissection for breast cancer
Breast cancer
Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas...
; radical neck dissection for head and neck cancer
Head and neck cancer
Head and neck cancer refers to a group of biologically similar cancers that start in the upper aerodigestive tract, including the lip, oral cavity , nasal cavity , paranasal sinuses, pharynx, and larynx. 90% of head and neck cancers are squamous cell carcinomas , originating from the mucosal lining...
and thyroid cancer
Thyroid cancer
Thyroid neoplasm is a neoplasm or tumor of the thyroid. It can be a benign tumor such as thyroid adenoma, or it can be a malignant neoplasm , such as papillary, follicular, medullary or anaplastic thyroid cancer. Most patients are 25 to 65 years of age when first diagnosed; women are more affected...
; D2 lymphadenectomy for gastric cancer; and total mesorectal excision
Total mesorectal excision
Total mesorectal excision is a standard technique for treatment of colorectal cancer, devised some 20 years ago by Professor Bill Heald at the UK's Basingstoke District Hospital. A significant length of the bowel around the tumour is removed, and the removed lymph system scrutinised for cancerous...
for rectal cancer
Colorectal cancer
Colorectal cancer, commonly known as bowel cancer, is a cancer caused by uncontrolled cell growth , in the colon, rectum, or vermiform appendix. Colorectal cancer is clinically distinct from anal cancer, which affects the anus....
.
More recently, the concept of sentinel lymph node
Sentinel lymph node
The sentinel lymph node is the hypothetical first lymph node or group of nodes reached by metastasizing cancer cells from a primary tumor.-Physiology:...
mapping has been popularized by Dr. Donald Morton and others. Cancer with various primary sites, breast, melanoma, colorectal, etc., often metastasize early to the first drainage lymphatic basin. This process is predictable anatomically according to the primary site in the organ and the lymphatic channels. The first nodes (sentinel nodes) can be identified by particulate markers such as lymphazurin, methylene blue, India ink and radio-labelled colloid protein particles injected near the tumor site. The draining sentinel node can then be found by the surgeon and excised for verification by the pathologist if tumor cells are present, and often these tumor cells are few and only easily recognized by careful examination or by using techniques such as special stains, i.e. immunohistochemical. When the sentinel node is free of tumor cells, this is highly predictive of freedom from metastasis in the entire lymphatic basin, thus leading to futility of a full node dissection.
The practice of sentinel lymph node mapping has changed the surgical approach in many cancer systems, sparing a formal lymph node dissection for patients with sentinel lymph node negative for tumor and directing a full node dissection for patients with sentinel lymph node positive for tumor metastases. For example in stage II breast carcinoma, using the sentinel lymph node technique, 65% of patients could be spared from a formal node dissection.