What's the abnormalities?

12 year boy, complaint of pain and swelling in left upper arm. What is the diagnosis?

Good evening Curofians. Posted below is a clinical image of a lesion. 1. Describe your clinical findings. 2.Differential diagnosis. 3.Approach towards this case. Clues : a. Long standing swelling since years. b. Swelling soft to firm. Please answer precisely and to the point against correct serial number, as weightage of accepted answer depends on these. Thank you very much. Best regards. [Credit : Dr.Kazi Wajid Husain,. MD]

28 yr male scalp lesion... measuring @ 3x 2 cm .hard in consistency.....

A 65-year-old man was detected with a small mass under the scalp at the right frontal region. The mass was slowly growing without pain. What can be the possible reason??

13 year old female, biopsy nasal bone with a growth facial region extending into the orbit