What is the concerning size of a submental lymph node?

From the Guidelines

Submental lymph nodes larger than 1.5 cm in diameter are generally considered concerning and warrant further evaluation. While lymph nodes can temporarily enlarge due to infections like colds or dental issues, persistent enlargement beyond 1-2 weeks, nodes that are hard, fixed, painless, or rapidly growing are particularly worrisome 1. Other concerning features include nodes larger than 2 cm, accompanying symptoms such as unexplained weight loss, night sweats, fever, or difficulty swallowing. If you notice an enlarged submental lymph node with any of these characteristics, you should seek medical attention promptly. Your healthcare provider may recommend imaging studies like ultrasound or CT scan, or possibly a fine needle aspiration or biopsy to determine the cause. Enlarged submental lymph nodes can result from various conditions ranging from benign infections to more serious issues like cancer, particularly oral, throat, or salivary gland malignancies, so timely evaluation is important for proper diagnosis and treatment.

Some key points to consider when evaluating submental lymph nodes include:

• The size of the lymph node, with nodes larger than 1.5 cm being more concerning 1
• The presence of accompanying symptoms such as unexplained weight loss, night sweats, fever, or difficulty swallowing
• The persistence of the enlarged lymph node beyond 1-2 weeks
• The presence of hard, fixed, painless, or rapidly growing nodes
• The need for imaging studies or biopsy to determine the cause of the enlarged lymph node

It's also important to note that the evaluation of submental lymph nodes should be done in the context of the patient's overall health and medical history, and that a thorough physical examination and medical history should be taken before deciding on further evaluation or treatment 2.

In terms of response criteria, a complete response (CR) is defined as all lymph nodes being less than 1.5 cm in diameter, or biopsy negative for lymphoma, while a partial response (PR) is defined as a cumulative reduction of 50% of the sum of the product of the longest bidimensional diameters (SPD) of the lymph nodes at baseline, with no new lymph nodes larger than 1.5 cm in diameter 3.

Overall, enlarged submental lymph nodes should be evaluated promptly and thoroughly to determine the underlying cause and to guide further treatment.

From the Research

Submental Lymph Node Size Concerns

• The size of submental lymph nodes can vary, with a mean number of 7.2 nodes detected by preoperative MRI, as reported by 4.
• The mean size of submental lymph nodes was found to be 5.28 ± 1.29 mm in a study using computed tomography angiography (CTA) 5.
• Lymph node size is not a highly reliable criterion for malignancy, as stated in 6.
• A study found that nodes with metastases had a round configuration, with a statistically significant greater short-axis to long-axis ratio than that of benign nodes 7.
• The distribution and size of lymph nodes can vary, and conducting a CTA scan may aid in maximizing the number of transferred lymph nodes and flap design 5.

Diagnostic Methods

• Ultrasound-guided fine-needle aspiration cytology (US-guided FNAC) can provide additional information about enlarged lymph nodes and show malignancy in small lymph nodes not found by other methods 6.
• Core needle biopsy (CNB) without fine-needle aspiration (FNA) can be sufficient to obtain an actionable diagnosis in cases of suspected lymphoma 8.
• Computed tomography (CT) and magnetic resonance imaging (MRI) can be used to detect lymph node metastases, but may not always be accurate 6, 4, 7.