Cryosurgery & Curettage Technique
Written 1st April 2020 - Last Update 21st July 2026
Cryosurgery & Curettage Technique
Cryosurgery
Treatment regime for common skin conditions in general practice, per the RACGP AFP article on optimising cryosurgery technique:
| Lesion | Technique | Time / freeze-thaw cycles (FTC) | Margin | Sessions, interval | Expected response |
|---|---|---|---|---|---|
| Viral warts (pared first to remove excess hyperkeratosis) | Flat: FTC. Plane: open-spray (OS), E-tip. Plantar: OS, B/C nozzle. Filiform/digit: OS, needle probe | Flat 10s ×1; plane 3–5s ×1; plantar 10–20s ×1; filiform/digit 10s ×1 (recalcitrant lesions may need a double FTC) | 1mm | 2 sessions, 2 weeks apart | 45–85% (depends on lesion number, user, technique) |
| Spider naevus | Cryoprobe (P) | 10s ×1 | 1mm | 3 sessions, 6 weeks | Good |
| Seborrhoeic keratosis | OS, cotton-tipped dipstick (D), or P | Ice formation ×1 | 1mm | Usually single treatment | Excellent |
| Skin tag | OS or forceps | 5–10s ×1 | 1mm | Usually single treatment | Excellent |
| Actinic keratosis | OS | 15s ×1 | 1mm | Single session, healing within 10 days | 86–99% |
| Solar lentigo | OS | 5s ×1 | 1mm | Single session | — |
| Bowen’s disease | OS | 15–30s ×1 | 3mm | Single session | Excellent (up to 98%) |
| Basal cell carcinoma (appropriate lesions only) | OS | 30s ×2 | 5mm | — | — |
| Dermatofibroma | P or OS | 20–30s ×1 | 2mm | 2 sessions, 8 weeks apart | — |
| Pyogenic granuloma | OS | 15s ×1 | 1mm | Single session | — |
| Cherry angioma | P | 10s ×1 | 1mm | Single session | — |
D = dipstick; OS = open-spray; P = cryoprobe.
Curettage and cautery
Curettage is an underused technique — historical Australian data (2006) found only 38% of GPs used curettage for BCC, despite evidence that cure rates are equal to excision, cryotherapy, and radiotherapy for suitable lesions, and better than imiquimod or photodynamic therapy (PDT).
Lesion selection: low-risk BCC, SCC-in-situ/Bowen’s disease, and keratoacanthoma are well-suited to curettage. Technique and lesion selection matter — curettage is not appropriate for high-risk or poorly demarcated lesions, which need excision with histological margin assessment.
See Skin Biopsy, Excision & Simple Repairs for punch/shave/excisional biopsy technique and keratinocyte-cancer excision margins — the alternative to curettage when a lesion needs histological margin assessment.