Brief Answer: Laser hair removal Detailed Answer: Hello, Welcome to healthcare magic, Laser for hair removal targets the melanin in the hair. After shaving the area, when laser beam falls on the skin, hair under the skin which is rich in melanin captures the light and light is converted to heat energy. This heat energy damages the hair follicle thus causing hair reduction. It is a safe procedure. Now about the beauty mark. By beauty mark you mean a mole I presume. Mole is rich in melanin, just like the hair. Therefore even a mole will capture the laser beams and get heated up causing burn and swelling. Therefore laser should not be used over a mole to prevent this side effect of burns. Next time the mole should be covered or avoided during laser session. Lymphnodes are under the skin and deep. These laser beams do not penetrate so deep and therefore won't cause any harm to lymph nodes. Laser hair removal has been in the field for many years now and its safety is established. It can cause side effects like burns immediately, but apart from that no long term side effects like skin cancer has been reported. Hope this helped, Take care.

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