Excisional biopsy

• removing the full lesion with surrounding normal tissue (including the adipose tissue) with 2mm clear margin
• Indication – Melanomas, Skin cancers and bullous lesions
• Method – elliptical incision (made with length three times the width with an angle of 30)

Note : used only in less than 2cm size lesions , not take in sensitive area (lips, eye, ear)

Incisional biopsy

• part of the lesion with a part of normal tissue is removed for comparison. (both epidermis and dermis)
• Indication – Granulomas, Lymphoid infiltrate, SCC 
• Method – surgical cut is made through the skin to remove a sample of abnormal tissue or part of a lump on suspicious area.

Note : deeper incision is better than a wider one

Punch biopsy

• full thickness skin biopsy (epidermis, dermis, subcutaneous)
• Indication – solid lesion , small vesicle, pyogenic granuloma
• Method – stretch the skin area first, then rotate the sharp cutting tool in circular motion to get a tube-shape piece of skin.

Shave biopsy

• superficial lesion (epidermis, papillary dermis) 
• Indication – Seborrhoeic Keratosis, Naevi
• Method – 1mm depth of skin was shaved or taken by using blade (scalpel or razor), then apply aluminium chloride 20% solution (drysol) to control bleeding, but that will never be used in melanoma.

Important Notes

• Punch and shave biopsy – for benign lesion
• Excisional and incisional biopsy – for malignant lesion

Fine needle aspiration 

• Indication – epidermal cyst, papulo-nodular lesions, BCC, SCC
• Procedure – to extract sample fluid or tissue from a cyst or a solid mass.

Dr. Aye Min Htoo

Dermatologist