Brief Answer:
Doctors exam and a few investigations mandatory

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help.

A lump/bump at the location described by you could have multiple etiologies or have various causes. There do exist lymph nodes around the collar bone that could have inflamed due to an infection, etc. The growth could be a cyst, a tumor, and so on.

I would recommend a doctors visit and the following to be conducted:
-Physical examination by a doctor (to check consistency, mobility, rule out breast involvement, etc.)
-Chest x-ray
-CT scan or MRI of the region
-If required, ultrasound guided aspiration of the region to send tissue samples to the laboratory

I do not wish to alarm you ma'am, but all lumps need to be investigated. I would prefer not taking chances with any of my patients, and always ruling out the worst to be able to treat the more simple causes with more ease.

I hope you understand why I prefer sending you to a doctor. I also hope we both find out that this is nothing serious and you continue to live a healthy and happy life ahead. Please feel free to write back to me for any further clarifications, I would be more than happy to help you.

Best wishes.

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