| Title |
Modified Johnson Square Procedure for Periocular Lentigo Maligna and Lentigo Maligna Melanoma: A Single Centre UK Study |
| Submitted by |
Huw Oliphant |
| Abstract Number |
319 |
| Abstract ID |
19-181 |
| Review Result |
poster presentation |
| Purpose |
Lentigo maligna (LM) and lentigo maligna melanoma (LMM) in the periocular region are rare entities, and are often difficult to manage due to poorly defined borders and the presence of sub clinical spread. Recurrence rates for LM/LMM with standard excision techniques range from 9-31%. The purpose of this case series is to demonstrate outcomes using a modified Johnson square procedure for LM and LMM in the periocular region. |
| Methods |
Retrospective review was undertaken for all patients undergoing modified Johnson square procedure for LM/LMM in a single centre (Royal Victoria Infirmary, Newcastle). Modified Johnson square procedure involves marking a 2-3mm margin around the lesion, with an additional 2-3mm margin around the first to complete a total 5mm margin. These strips are assessed using en face permanent section histological analysis by fellowship trained Mohs surgeons, with further margins taken where positivity is found. |
| Results |
Twenty eight patients were included. Average age was 73 (range 50-95). Twenty patients were categorised as LM, 8 LMM, with 26 representing primary disease, and 2 recurrent. Mean duration of lesion was 44 months (range 4-180 months). Mean number of stages required was 2 (range 1-5). Mean follow was 18 months (range 6- 51 months). Mean diameter of pre operative lesions was 19.5 x 13.8mm, mean post excision defect was 32.7 x 21.9mm. Two patients had local recurrence (7.1%). All defects underwent primary closure, or delayed closure under oculoplastics. |
| Conclusion |
To our knowledge this represents the largest cohort of patients with periocular LM/LMM treated using a modified Johnson square procedure, interpreted using en face permanent section histological specimens by a Mohs surgeon. The recurrence rate is lower than standard excision techniques, though slightly higher than some quoted microscopic margin control techniques. |
Additional Authors
| Last name |
Initials |
City / Hospital |
Department |
| Lawrence |
C |
Royal Victoria Infirmary/Newcastle |
Dermatology |
| Langtry |
J |
Royal Victoria Infirmary/Newcastle |
Dermatology |
| Clarke |
L |
Royal Victoria Infirmary/Newcastle |
Ophthalmology |
| Oliphant |
T |
Royal Victoria Infirmary/Newcastle |
Dermatology |
