Skin Surgical Techniques

1. Skin Surgical Techniques

2. Biopsy – Shave vs Punch • Shave a lot faster • Haemostasis less of a problem (Driclor) • Useful for tumours, papules, pedunculated lesions, ID naevi, Macular PSL • Punch is appropriate for inflammatory skin diseases and tumours where sample of tissue depth necessary (usually more indurated lesions)

3. Excisional Biopsy

4. Shave Biopsy

5. Punch Biopsy

6. Excision – Shave vs Punch • Depends on type of tumour • Shave - epidermal lesions (achrocordon, some intradermal naevi, KAs) • Punch – ID naevi face, vascular tumours eg capillary haemangioma, seb hyperplasia • NB melanocytic naevi with hairs will only stop growing hair if dermis/subcutis excised

7. Excisional Biopsies • Avoid danger areas such as pre-auricular, angle of mandible and posterior cervical triangle • plan excision along relaxed skin tension lines • use 3:1 ratio and mark site with gentian violet marker • use appropriate anesthesia (I.e. no epinephrine on finger tips, nose tip, tip of penis)

8. Ellipse

9. Tense closures • Sites eg scalp, lower leg • Undermine • Assistant • Stronger suture material • Vertical Pulley, Butterfly (double butterfly), Traction sutures

12. Weak, thin skin • Eg Scleroderma, Solar damage, Corticosteroid use – partic lower legs • Deep sutures • Assistant, Steri-strips, Crepe bandage • Secondary intention healing • SSG, FTSG • Avoid, Refer

13. Suture removal – general guide • Face – 7 days • Neck – 10 days • Trunk, Limbs – 12-14 days, (7-10 days if deep sutures in place)

14. Moh’s Surgery

15. MOHS’ SURGERY What is it? • Form of skin cancer surgery for SCC, BCC, KA, +/- Melanoma • Highest cure rate for primary and secondary cancers • Dermatologist - surgery, pathology and repair

16. MOHS’ SURGERY How is it done ? Principles • Remove tumour • Repair to suit function • Cosmesis

17. METHOD CONT’D • Any remaining tumour is located on the slide and further surgery is done to this area • Above steps are repeated until all tumour is removed • Defect is repaired

18. MOHS’ SURGERY Indications • BCC/ SCC/ Other tumours • Located on the central face or periorifical areas (eyes, mouth, nose, ears, etc) • Recurrent tumours • Incompletely excised tumours • High risk histological types eg morphoeic BCC • Large or ill-defined lesions • Young patients with skin cancers

19. MOHS’ SURGERY Advantages • Tissue conservation • Highest cure rate • Local anaesthetic procedure • Cost to patient is no different to standard surgery

20. MOHS’ SURGERY Disadvantages • Time consuming for doctor and patient • Expensive equipment • Expertise required

21. Mohs Micrographic Surgery • Recurrent tumors • Tumors >2 cm • Aggressive Histology • Ill-defined margins • Incompletely excised tumors • Local cure rates >99%

22. Needle Selection • Cutting-most skin surgery. • FS- for skin • P, PS, PRE for cosmetic areas • Taper-fascia and bowel • Blunt-liver and kidney • Higher number=smaller needle • Use larger needles for deep tissue, smaller needle to close the skin.

23. Needle Types

24. Skin Grafts • Split Thickness Skin Grafts -include part of the dermis and all of epidermis -donor site regenerated from hair follicles and skin edges on the graft • Full Thickness Grafts -less wound contracture -usually used for palms and back of hands

25. Evolution of Skin Grafts

26. Flaps • Free Flaps -predisposed to venous thrombosis TRAM flaps • Rely on superior epigastric vessels for blood supplu • Periumbilical perforators are the most important determinant of TRAM viability

27. Squamous Cell Carcinoma • Risk Factors – actinic keratoses, zeroderma pigmentosum, bowen’s disease, atrophic epidermitis, arsenic, coal tar, nitrates, HPV, fair skin, XRT exposure • Tx: .5-1.0cm margins for low risk • Reginal adenectomy for positive nodes • Mohs Surgery – margin mapping using conservative slicles, never used for melanoma, best for facial lesions

28. Melanoma Staging

29. Management

30. Sentinel Lymph Node • No more elective node dissection • Nodal status is a strong prognostic factor • Indicated for melanomas >1 mm • Lymphazurin blue and 99Tc- sulfur colloid

31. Melanoma Adjuvants • Chemotherapy usually not too effective • Dacarbazine: 20% response • Interferon alpha: 20% response • Isolated limb perfusion – Melphalan: 80 % • Immunotherapy: 15% response • Melanoma vaccines?

32. Squamous Cell Carcinoma • 250,000 cases/year, 2nd most common skin CA, 2500 deaths/yr • Bowen’s Disease: early stage or intraepidermal form of SCC • Poor prognostic factors: >2 cm deep, poorly differentiated, rapid growth, originating in scar, perineural involvement • Only 50% 5-year survival if nodes involved

33. Treatment Options • Wide local excision: >4-7 mm margins to deep subcutaneous tissue • Radiation for poor surgical candidates • Mohs micrographic surgery • Cryosurgery • Currettage and Electrodessication • Laser ablation • Topical 5-FU

34. Basal Cell Cancer • 900,000 cases/year, lifetime risk for Caucasians 30%, rarely metastasize • Local destruction, 30% develop non-melanoma skin CA recurrence within a year • Excise with negative margins (4-7 mm) • Lymphadenectomy only for basosquamous variant with clinically (+) nodes • Moh’s is best for high risk lesions