How likely is the painful lump on inside of knee cancer lump isnt attatched to bone knee swelled tight at the bk hurts more after use 3 weeks now?

Best examined: While a tumor often forms a lump, it isn't necessarily painful. That often depends on its location. Soft tissue sarcomas and lymphomas can appear at that location, but other diagnoses are more likely. This includes varicose veins, inflamed tendons, boils, Baker's cyst, venous thrombosis, etc. It's best to have the area examined by your physician.