Development of Mondor's disease 17 years after breast augmentation surgery?

Thank you for sharing your question and I am sorry to hear of your Mondor's Cords.  Though typically found in the initial recovery from surgery, Mondors can take place at any time as it is an irritation/inflammation of the veins in that region.  Typically treated with warm compresses and NSAID's it should pass quickly.  If it does not I would see your internal medicine doctor for an evaluation. 

No, this is not Mondors phenomenon so many years after BA. Mondors is blockage of superficial veins that occur at the time of surgery and appear right away or after edema resolves. You should see your primary care doctor or gynecologist for breast evaluation urgently.Best of luck!

Mondor's disease is thought to be superficial thrombophlebitis of the chest wall.  
It does occur soon after breast augmentation.  It sounds scary and terrible, but usually is just a temporary inflammation of the veins of the chest wall which causes a characteristic cord or hard band at the bottom of the breast that usually resolves by itself in a few weeks.    Anti-inflammatory medicines like ibuprofen may help.  
Late banding makes me concerned for early capsular contracture.  Another answer below suggested breast cancer, but I think that would be less likely.  
Either way, an evaluation of the breast and the implant seems appropriate to sort out what this is, or isn't.  

Mondor's disease or inflammation of the superficial veins is usually seen early after the breast augmentation surgery, often on the chest wall or on the lower portion of the breast.  This inflammation resolves with topical treatment.  I would see your primary doctor for a complete evaluation as this may not be Mondor's disease or phenomenon.  FACT:  Liposuction removes unwanted fat from any area treated.FACT:  Skin that has been stretched to cause stretch marks ( like after pregnancy or large weight loss, like >100lb) has LOST ELASTICITY.   The more fat removed, the more extra skin can show.  FACT: Not every "tummy' after pregnancy is JUST FAT.   There could be inner core weakness.FACT:  Just because you COULD have a tummy tuck, does not mean that you MUST have a tummy tuck. ANSWER:   Is liposuction a good choice after pregnancy?  It all depends on what you will feel is a result that will make you feel better about your body and your self. Ask yourself:
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Mondor's Disease occurs in about 1% of breast augmentation patients, but typically soon after surgery.  Since you are now 17 years out,  I would highly recommend that you be evaluated by your primary doctor because there is a small chance that this could be associated with a breast cancer.  I'm not trying to frighten you, but your question cannot be answered without an evaluation in person.