Hello I would see these possibilities for these brown spots , these includes . 1 Eczematous dermatitis as this is the most common site . Mild itching present but no pain ( as you mentioned in your query). Diagnosis can be confirmed by physical examination by a dermatologist . 2 Fungus infection is another such cause . Diagnosis can be confirmed by scratch test by a dermatologist . 3 Psoriasis is the another such cause , so diagnosis can be confirmed by physical examination by a dermatologist . In my opinion you must consult a dermatologist and get his opinion as physical examination is important in this type of cases. Good luck.