Brief Answer:
Mondor's disease / get confirmed / rule out underlying tumor or so

Detailed Answer:
Hi.
Thanks for your query and an elucidate history.

This is a condition called iodiopathic thombophlebitis of the superficial vein.
The exact reason is not known why it occurs.Mondor's disease is a rare condition, which involves the thrombophlebitis of the superficial veins of the breast and anterior chest wall
This is usually a self-limiting disorder and does not cause any aftereffects. So nothing to worry about, provided you have to consult a Doctor to get a confirmed diagnosis by clinical evaluation, ultrasonography of the area, the breasts and the axilla to rule out any underlying pathology like a tumor or so.

Once confirmed, needs no special treatment other than symptomatic like a painkiller with anti-inflammatory medicines like Ibuprofen if it suits you.

May be hot compresses help.
Some Doctors prefer to give Doxycyclin and oral steroids on empirical basis.

I hope this answer helps you to get a proper diagnosis, and get a proper further treatment. Please feel free to ask for more or if you need further clarifications or if you feel there is a gap of communication.

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Brief Answer:
Letrozole changes the hormonal balance, but literature does not indicate so

Detailed Answer:
May I please know the reasons for which you are taking Letrozole.

It may or may not be responsible.
Sometimes, dehydration is responsible for such presentation.

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Brief Answer:
please continue but tell your Doctor

Detailed Answer:
The medicine you are taking and the problem you have must be in the knowledge of your treating Doctor.

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