Staged Excision of Lentigo Maligna of the Head and Neck: Assessing Surgical Excision Margins With Melan A, SOX10, and PRAME Immunohistochemistry.

BACKGROUND: Staged excision has emerged as a superior treatment option for lentigo maligna (LM) of the head and neck when compared with conventional wide local excision. Assessing surgical excision margins for remaining LM poses a diagnostic challenge. OBJECTIVES: To determine whether immunohistochemical (IHC) staining with SOX10 and preferentially expressed antigen in melanoma (PRAME) aids in diagnosing LM on excision margins compared with conventional hematoxylin and eosin and Melan A IHC staining. METHODS: This study included cases of LM of the head and neck treated with staged excision. Histological findings were reviewed according to standard criteria for the diagnosis of LM and compared with the results after IHC staining for Melan A, SOX10, and PRAME. RESULTS: The cohort consisted of 35 sections. Based on hematoxylin and eosin and Melan A IHC staining, 23 sections were diagnosed as LM by the initial pathologist. Further staining with SOX10 IHC showed only 8 to be consistent with a diagnosis of LM and 9 revealing features of actinic melanocyte hyperplasia. PRAME was positive in 5 of the 8 cases of LM and negative in all 9 cases of actinic melanocyte hyperplasia (P = 0.009). The presence of melanocyte nests (P = 0.29) and pagetoid spread (P = 0.003) was the most reliable histological findings distinguishing LM from its mimics. CONCLUSION: SOX10 is a more specific and sensitive marker for melanocytes when assessing for LM on excision margins compared with Melan A. The addition of PRAME can be useful to confirm or exclude the diagnosis in challenging cases.

Lentigo Maligna of the head and neck: A retrospective study assessing surgical excision margins in a South African population.

Background: Lentigo maligna (LM) is a subtype of melanoma in situ that occurs on sun-damaged skin and is associated with significant subclinical extension beyond the clinical margins of the lesion. Objectives: This study aimed to determine if the standard recommended tumor excision margins for LM are adequate to achieve a 97% clearance rate and if any patient or tumor characteristics warranted wider margins. Methods: This study is a retrospective chart review of all patients who were diagnosed with LM of the head and neck and treated with staged excision. Results: The study included 64 patients. With a 6 mm surgical excision margin, only 60.9% of LM were completely excised. A 9 mm margin resulted in complete clearance of 71.9% of LM cases, and a 12 mm margin resulted in complete clearance in 90.6%. A surgical excision margin of 18 mm would have been required to excise 96.7% of tumors completely. Recurrent tumors (P = .01) and tumor size larger than 20 mm were associated with wider surgical excision margins (P = .154). Conclusion: This study of LM in a South African population corroborates that the standard surgical excision margins recommended by international melanoma guidelines for LM are inadequate to achieve a 97% clearance rate.

Cross-sectional study of acral melanoma awareness in a group of South African final phase medical students.

BACKGROUND: Acral melanoma refers to melanoma arising on the palms, soles and nail unit, which are sun-protected areas and ultraviolet exposure is not a risk factor. Acral melanoma is associated with a poorer prognosis than other melanoma subtypes most likely due to the high rates of delayed diagnosis. Acral melanoma affects all skin types equally. There is a misconception that people with more pigmented skin types (Fitzpatrick 4-6) do not develop melanoma, due to the protective effect of melanin. OBJECTIVES: The aim of the study was to determine acral melanoma knowledge and awareness of a group of South African, final phase medical students. METHODS: This was a quantitative and cross-sectional study. A questionnaire consisting of 20 clinical images of skin lesions requiring a diagnosis and management plan was distributed. Responses to six images of melanomas were analysed. Further questions to measure acral melanoma knowledge and related issues were included in the study. A biostatistician appropriately managed statistical analysis. RESULTS: Hundred and one final phase medical students' answers were gathered and analysed. Only 7.9% of the participants diagnosed all six melanomas correctly; 61.4% correctly diagnosed ≥50% of the melanomas. While 77.2% of the participants identified all non-acral cutaneous melanoma correctly, only 8.9% identified all acral melanomas. However, of all participants making the correct diagnosis, >90% selected the appropriate management plan (urgent referral). LIMITATIONS: This study examined a small sample of trainee healthcare workers. The results cannot be assumed to apply to all South African healthcare workers. Responses given in a questionnaire may not reflect actual behaviour. The dermatology division in question has made acral melanoma a research priority, thus acral melanoma knowledge in this group may in fact be better than in other institutions. CONCLUSION: The present study demonstrates that groups of imminent doctors have low rates of recognition of melanoma, particularly acral melanoma. This is consistent with high levels of primary misdiagnosis of acral melanoma reported in the literature. Fortunately, these participants managed the melanomas they diagnosed appropriately in >90% of cases. This confirms that the deficit in the participant group is awareness and knowledge. Those aware of the disease immediately acknowledged the need for urgent referral.

The prevalence and spectrum of mucocutaneous disease in South African people living with HIV and accessing care at a district-level hospital.

BACKGROUND: Although the association between human immunodeficiency virus (HIV) and mucocutaneous diseases has been well studied within South African specialist centres, there is limited data from district-level hospitals. Available data may, therefore, fail to reflect the prevalence and full spectrum of dermatoses seen in people living with HIV (PLWH). OBJECTIVES: To determine the prevalence and spectrum of dermatoses seen in PLWH. METHOD: We conducted a cross-sectional, descriptive study of 970 PLWH (men and women, ≥ 18 years old) accessing care at Karl Bremer Hospital, a district-level hospital located in the Western Cape province, South Africa, between 01 September 2016 and 28 February 2017. RESULTS: The prevalence of mucocutaneous disease in this sample was 12.7% (95% confidence interval [CI] 0.11-0.15). Non-infectious dermatoses comprised 71.0% of the disorders. Pruritic papular eruption (20.0%) and seborrheic dermatitis (6.0%) were the most common non-infectious dermatoses. Tinea corporis (8.0%) and oral candidiasis (6.0%) were the most prevalent infectious dermatoses. There was no significant association between skin disease category (infectious or non-infectious dermatoses) and patient demographics (gender and ethnicity) or HIV-disease characteristics (CD4+ cell count, viral load and duration of antiretroviral therapy [ART]). CONCLUSION: This study provides valuable scientific data on the prevalence and spectrum of mucocutaneous disease in PLWH attending a South African district-level hospital. Prospective studies conducted in other district-level centres across the country are required to determine the lifetime prevalence and spectrum of dermatoses in PLWH in the ART era.

An Analysis of Biopsies for Suspected Skin Cancer at a Tertiary Care Dermatology Clinic in the Western Cape Province of South Africa.

BACKGROUND: Skin cancer is a growing health concern worldwide. It is the most common malignancy in South Africa and places a large burden on the public healthcare sector. There is a paucity of published scientific data on skin cancer in South Africa. OBJECTIVES: To report the findings of biopsies performed in patients with suspected skin cancer attending the Tygerberg Academic Hospital (TAH) Dermatology outpatient department (OPD) in the Western Cape Province of South Africa. Methodology: A retrospective chart review identified all patients who underwent a biopsy for a suspected skin cancer diagnosis between September 2015 and August 2016 at the TAH dermatology OPD. RESULTS: A total number of 696 biopsies from 390 participants were identified, of which 460 were histologically confirmed as malignant lesions. The proportion of clinically suspected skin cancers that were histologically confirmed as cancer was 68%. The most commonly occurring malignancies were basal cell carcinoma (BCC) (54.8%), squamous cell carcinoma (SCC) (18.9%), squamous cell carcinoma in-situ (SCCI) (8.0%), Kaposi's sarcoma (KS) (6.7%), malignant melanoma (MM) (6.1%), and keratoacanthoma (KA) (4.6%). The number needed to treat (NTT) for all cancers diagnosed and for MM was 1.5 and 4 respectively. BCC (89.3%) and KS (67.7%) was the most common skin cancer in the white and black population respectively. The ratio of BCC to SCC was 2.03. CONCLUSION: This study provides valuable scientific data on the accuracy of skin cancer diagnosis, distribution and patient demographics in the Western Cape Province of South Africa, on which further research can be based. The study highlights the burden of skin cancer on this specific population group and calls for standardised reporting methods and increased surveillance of skin cancers.