When a patient presents with a solitary neck nodule that is non-tender, the differential diagnosis includes:
Infectious etiology including an upper respiratory infection, a viral infection, sinus or periodontal abscess.
Thyroid nodule or thyroglossal duct cyst.
Enlarged or inflamed salivary gland.
Enlarged reactive node, usually post infection, post injury, or post intervention (biopsy or surgery in the head and neck).
Enlarged malignant node–this could be primary lymphoma, or metastatic cancer to a lymph node from skin, head and neck, thyroid, lung, breast, colon or other.
Neck nodule work-up medical expert witness specialties include head and neck surgery, otolaryngology, pathology, radiation oncology, oral and maxillofacial surgery, interventional radiology, and radiology.