I am a 49 female and felt a swollen supraclavicular lymphnode. got ultrasound. it's .6mm. they said everything was normal (no lymphadenopathy, normal morphologically, no masses or fluid). but isn't that too big? my doctor said no need to biopsy?

Supraclavicular lymphadenopathy is associated with a high risk of malignancy at your age. You did not mention what side the lymph node is. Do you have any symptom and sign of a viral illness or if you have any constitutional symptom such as fatigue, weight loss, low grade fever, etc? Watch the node & you are safe if it gets smaller. Biopsy is indicated if it gets bigger or if you have systemic sx.

You may feel the nodes every couple of weeks, if any of the lymph glands doubles in size, becomes painful, ulcerates, or other nodes become enlarged, or you develop fever, or lose weight, you should see a doctor. Wish you good health!