Welcome to the MedHelp forum!
Yes, supraclavicular lymphadenopathy (lymphnode in area between collar bone and jaw) is worrisome. Especially the ones larger than 1cm in diameter should be investigated thoroughly for cancers and granulomatous diseases. The right supraclavicular area receives drainage from the organs in chest, whereas the left supraclavicular lymph nodes drain the abdomen. The supraclavicular lymph nodes also receive lymphatic drainage from the breasts. Hence the malignancies of these regions are possible. Tuberculosis, sarcoidosis, histoplasmosis, cat scratch disease and cryptococcosis are the other possibilities.
Since I cannot examine your husband and know other related conditions he may be having, nor is a detailed history possible on net, I have listed the various possibilities that should be looked into. Please consult your PCP for primary examination followed by proper referral.
*infections, stress, poisons, possible disease warnings
Should be steady, and ready for future possible attacks
Thank you for your response!