Hello,

Thanks for posting your query.

Normally the lateral thoracic vein continues below as thoracoepigastric vein. It travels linearly below the breast to the abdomen to join the superficial epigastric vein in the lowest border where the trunk joins the thigh. This can be seen in thin individual as it superficial and lies close to the skin.

It is quite possible that you have noticed it after losing weight because the loss of subcutaneous fat has made it to appear prominent. It's normal and you need not worry. However if it is painful, tender, swollen or there is redness , itching etc then its likely to be indicating an underlying problem like thrombophlebitis (inflamed vein) or obstruction to major vessels.

Regarding the lumps and bumps, it is not clear about the size, location and consistency of these bumps.

Hope I have answered your query. Let me know if you have any more concerns.

Regards

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