From the Research
If you had a melanoma on your belly button, the most likely lymph nodes to be palpable would be the inguinal (groin) lymph nodes and possibly the axillary (armpit) lymph nodes. The belly button area has lymphatic drainage that can flow in multiple directions. Typically, melanomas in the umbilical region primarily drain to the inguinal lymph nodes located in both groins, but they may also drain to the axillary lymph nodes under the arms. This dual drainage pattern occurs because the umbilicus sits at a watershed area where lymphatic vessels from different regions converge. During physical examination, your doctor would carefully palpate these areas to check for enlarged, firm, or tender lymph nodes, which might indicate metastatic spread of the melanoma. The pattern of lymphatic spread is important for staging the melanoma and determining appropriate treatment, including whether a sentinel lymph node biopsy would be recommended to check for microscopic spread of cancer cells. Some studies, such as 1, have shown that the surgical management of the groin lymph nodes in melanoma patients is crucial, and that sentinel lymph node dissection can be an effective way to stage the disease. Additionally, fine needle aspiration cytology (FNAC) can be used to evaluate both palpable and nonpalpable lymph nodes, as shown in 2, with high sensitivity and specificity. However, the management of melanoma in the groin area can be complex, and the involvement of deep nodes can affect survival rates, as seen in 3 and 4. It's essential to consider the most recent and highest quality studies when making treatment decisions, and to prioritize the patient's morbidity, mortality, and quality of life. In this case, the most recent study 2 provides valuable information on the use of FNAC in evaluating lymph nodes, but the study 1 provides more relevant information on the surgical management of groin lymph nodes in melanoma patients. Therefore, the inguinal lymph nodes are the most likely to be palpable in a patient with a belly button melanoma, and a thorough physical examination and appropriate diagnostic tests, such as sentinel lymph node biopsy or FNAC, should be performed to determine the extent of the disease.