The investigators will use optical coherence tomography to detect the ex-vivo tissue image of surgical removed melanoma or other benign pigmented lesions of skin.

The investigators will use an advanced high resolution 3D optical coherence tomography (OCT) technology to observe skin tissue images in ex vivo culture. Parts of melanoma or benign pigmented lesions specimens derived from biopsy or surgical excision specimen will be observed by 3D optical tomography. A tiny tissue fragment of melanoma or benign pigmented lesions will be taken from surgical specimen without interference normal pathological evaluation. The location of melanocytic cells in melanoma or benign tissue fragments will be mapped by the 3D optical coherence tomography (OCT). The 3D optic tomography system utilize a Ce:YAG optical fiber as light source and also combined with confocal microscopy. Taken together, these features made the 3D optic tomography system have very high resolution and suitable for single cell imaging. This study will not interfere with the normal medical practice and had no impact on patient's safety and health. All of the materials will be destroyed once the experiments are done. The enrollment criteria will be dermatological patients who need to surgical intervention.

Inclusion Criteria:

• Patients aged older than 20 years old
• Patients who had melanoma, melanoma in situ, and/or other benign pigmented lesions,
• Patients who had non-melanoma skin cancers (basal cell carcinoma, or squamous cell carcinoma).
• Patients who had precancerous skin lesions (Bowen's disease, actinicc keratosis)

Exclusion Criteria:

• Pregnant women.

Participants are patients at out-patient clinics or ward of Department of Dermatology, National Taiwan University Hospital.