From the Guidelines
The fat anterior to the psoas muscle below the lower pole of the left kidney is indeed part of the lymphatic chain for renal cancer, as it contains para-aortic lymph nodes that serve as a primary drainage pathway for the left kidney. This area is clinically significant in kidney cancer management, as the lymphatic drainage of the kidney follows a predictable pattern along the renal vein and artery toward the para-aortic nodes 1. When kidney cancer metastasizes, it typically spreads first to these regional lymph nodes before advancing to distant sites.
Key Points to Consider
- The lymph nodes in this region are often removed as part of a regional lymphadenectomy during surgical management of kidney cancer (radical nephrectomy) to properly stage the disease and reduce the risk of recurrence 1.
- Understanding the anatomical relationship between the kidney and the lymphatic chain is important for proper surgical planning, accurate staging, and determining appropriate adjuvant therapy for patients with renal cell carcinoma.
- The staging of renal cell carcinoma (RCC) is based on size, position, and lymph node involvement, with stage III tumors potentially involving one regional lymph node, and stage IV tumors involving distant metastases or more than one regional lymph node 1.
Clinical Implications
- Radical nephrectomy with lymph node dissection is recommended for patients with clinical enlarged lymph nodes or those with stage III RCC, while systemic therapies might be the only available option for those with extensive disease and poor performance status 1.
- The removal of the fatty tissue containing lymph nodes anterior to the psoas muscle is a crucial step in the surgical management of kidney cancer, as it allows for accurate staging and reduces the risk of recurrence 1.
From the Research
Lymphatic Chain for Renal Cancer
The lymphatic chain for renal cancer is a complex system that involves various lymph nodes and lymph ducts.
- The primary lymphatic sites for each kidney are the lymph nodes along the great vessel and the interaortocaval region 2.
- Lymph node metastases in renal cell carcinoma (RCC) tend to progress through the primary lymphatic drainage of each kidney 2.
- The extent of lymph node dissection (LND) remains a matter of controversy, but an extended LND may be beneficial in patients with locally advanced disease or unfavorable clinical and pathologic characteristics 3.
Fat Anterior to the Psoas Muscle
The fat anterior to the psoas muscle is not specifically mentioned as part of the lymphatic chain for renal cancer in the provided studies.
- However, the psoas muscle itself can be a rare location for metastasis of renal cell carcinoma, with only one case of solitary metastasis to the psoas muscle reported 4.
- Fat necrosis can also occur in the vicinity of the psoas muscle and can mimic recurrence of renal cell carcinoma on imaging 5.
Lymph Node Dissection
Lymph node dissection is an important aspect of the surgical management of renal cell carcinoma.
- The study by 2 recommends removing lymph nodes from the ipsilateral great vessel and the interaortocaval region, from the crus of the diaphragm to the common iliac artery.
- The study by 3 suggests that an extended LND may be beneficial in patients with locally advanced disease or unfavorable clinical and pathologic characteristics.
- The study by 6 found that systematic lymph node dissection can be performed safely with low morbidity and mortality, and recommends that it should be demanded in every patient due to the high prevalence of intrathoracic lymph node metastases.