Delays in the referral and primary management of cutaneous malignant melanoma at Tygerberg Hospital

Background: Cutaneous malignant melanoma (CMM) is a significant cause of skin cancer-related mortality. The time between the diagnostic biopsy and primary surgical excision, the surgical interval (SI), is a modifiable factor that may impact melanoma outcomes. Delays in the SI are attributable to many factors.Aim: To determine the SI in patients with resectable CMM treated at Tygerberg Academic Hospital (TAH).Methods: A retrospective review of patients referred to the TAH multidisciplinary melanoma clinic with histologically confirmed CMM between January 2015 and December 2017 was done. Patients 18 years with resectable melanoma (T1b-T4b N0-3 M0-1a) who received definitive surgery were included.Results: The cohort (n = 40) comprised mostly Caucasians referred from the Cape metropolitan (metro) area, with a median age at diagnosis of 59 years. Thirty-one (77.5%) patients had T3 or T4 lesions on diagnostic biopsy. Twenty patients (50%) underwent a sentinel lymph node biopsy (SLNB) which led to an upstaging in 20% of cases. The median length of the SI was 13.5 weeks. Eighteen patients (45%) underwent primary excision within the recommended 12 weeks from diagnostic biopsy. There was a significant association between the SI and patients living in the Cape metro (p = 0.04) as well as the SI and p Stage (p = 0.01).Conclusion: Surgical interval guidelines for cutaneous melanoma are poorly defined. We used 12 weeks as an extrapolation of international guidelines. Even though this target was not met, the study is proposed to be of value in guiding future protocols and ultimately allowing for improved, timely service to patients.

Recent Malignant Melanoma Epidemiology in Upper Silesia, Poland. A Decade-Long Study Focusing on the Agricultural Sector

The aim of the present study was to create spatial and spatio-temporal patterns of cutaneous malignant melanoma (MM) incidence in Upper Silesia, Poland, using the largest MM database (<4K cases) in Central Europe, focusing on the agricultural sector. The data comprised all the registered cancer cases (C43, according to the International Classification of Diseases after the 10th Revision) between the years 2004–2013 by the Regional Cancer Registries (RCRs) in Opole and Gliwice. The standardized incidence ratios (SIRs), spatio-temporal growth rates (GRs), and disease cluster relative risks (RRs) were estimated. Based on the regression coefficients, we have indicated irregularities of spatial variance in cutaneous malignant melanoma, especially in older women (≥60), and a possible age-migrating effect of agricultural population density on the risk of malignant melanoma in Upper Silesia. All the estimates were illustrated in choropleth thematic maps.

HSP105 expression in cutaneous malignant melanoma: Correlation with clinicopathological characteristics

Background Heat shock proteins can protect against stress-associated cellular challenges, but they can also protect some tumors from human immune system monitoring. Heat shock protein 105 (HSP105/110) is a high molecular weight protein whose expression has been reported in many cancers, but few studies on its role in cutaneous malignant melanoma have been published. In this study, we analyzed the relationship between HSP105 expression and the clinicopathological characteristics of CMM. Methods This retrospective study included 91 patients with CMM. The clinicopathological characteristics of CMM patients, including age, lesion duration, location, pathological classification, Clark’s level, Breslow thickness, metastasis and recurrence, were collected. Immunohistochemical staining and Western blot analysis for HSP105 were performed. Pigmented nevi (n = 20) served as a control. The staining intensity and percentage of stained cells were expressed as a histochemical score (HSCORE). Results HSP105 was overexpressed in melanoma compared with nevi. Differences in the HSCORE between nevi (HSCORE = 1.05(0.15,1.50)) and CMM (HSCORE = 2.68(1.80,3.60)) were remarkable (P<0.001). Exposed site lesions, recurrent and metastatic lesions, nodular melanoma and lentigo maligna melanoma were closely associated with higher HSP105 expression (P = 0.011, P = 0.001 and P = 0.001, respectively). Moreover, no significant difference was observed in Clark’s level, Breslow thickness, or lesion duration (P>0.05). Conclusion HSP105 is overexpressed in CMM. Higher HSP105 expression in lesions is associated with different clinicopathological variables. HSP105 may be a potential target for the diagnosis, treatment and prognostic prediction of CMM.

1099 Financial Implications of Implementing MSLT-II Trial Findings for Treatment of Cutaneous Malignant Melanoma Patients in A Tertiary Referral Centre in The United Kingdom

Aim Cutaneous malignant melanoma is a significant public health challenge in the United Kingdom. Since the new American Joint Committee on Cancer (AJCC) version 8 definition of melanoma staging, more melanoma patients are eligible for sentinel lymph node biopsies (SLNB). Prior to the MSLT-II trial, SLNB positive patients were treated as a distinct group within cutaneous melanoma patients and in most centres would routinely undergo lymph node clearance (LNC) of the regional lymph node basin to control disease. Given the above developments in melanoma care, we compared the cost of SLNB and monitoring to the cost of LNC for patients with melanoma. Method We retrospectively reviewed all SLNB positive patients undergoing LNC or surveillance in 2019. We measured the cost of all clinical encounters for both groups and performed a cost analysis. Results Our study shows that the mean cost per patient of axillary LNC is £4731.64 and groin LNC is £5381.78 against a cost of £2896.67 for SLNBs. Mean inpatient stay was 2.8 nights following LNC and 0.11 nights following SLNB. 50% of LNCs and 11% of SLNBs were associated with post-operative complications. Conclusions Our data shows that treating uncomplicated SLNB positive patients with surveillance rather than immediate LNC results in reduced morbidity, lower complication rate and shorter inpatient stay for the patients, as well as lower financial burden to the unit. This is reflected by the UK Consensus statement on melanoma, suggesting that LNC should not be routinely offered for positive SLNB without high-risk features.

1092 Impact Of MSLT-II on Lymph Node Clearance Surgery in A Tertiary Plastic Surgery Centre

Aim Cutaneous malignant melanoma is a significant public health challenge in the United Kingdom. Wide local excision with Sentinel Lymph Node Biopsy (SLNB) is the current standard of treatment for most lesions. Some patients with positive SLNB would routinely undergo locoregional Lymph Node Clearance (LNC). Results of the Multicenter Selective Lymphadenectomy Trial II (MSLT-II) published in August 2017 challenged this approach, showing no melanoma specific survival benefit, but significant morbidity associated with routine LNC. Our study aims to show a change in practice at a tertiary plastic surgical referral centre in response to these results. Method We retrospectively reviewed our prospectively maintained database for all LNCs performed for cutaneous, non-head and neck malignant melanoma using the search terms ‘clearance’ and ‘dissection’ between 2015 and 2019. Results We performed 128 axillary and groin LNCs for cutaneous malignant melanoma 2015-2019. The range of LNCs per year varied from 38 in 2015 to 10 in 2019 (mean 25.6, median 28). The total number of LNCs, as well as LNCs performed following positive SLNB decreased after August 2017. Conclusions The data shows that our centre acknowledged evidence and reduced the number of LNCs performed after publication of MSLT-II. We expect that the number of avoided LNCs has saved significant resources due to reduced length of stay, and avoided our patient’s significant morbidity, including seromas, infections and lymphoedema. We recommend all skin cancer treatment centres to follow the evidence in order to provide excellent care and save resources.

1337 A Regional Review of The Epidemiology and Pathological Characteristics of Malignant Melanoma in Northern Ireland (NI), And Correlation with Socio-Economic Status

Introduction The incidence of cutaneous malignant melanoma is increasing. Internationally, there is evidence of an association between melanoma incidence and higher socioeconomic status (SES). This study aims to assess the characteristics of patients with melanoma in NI, and correlate to SES. Method Retrospective review of electronic records for patients undergoing surgery for melanoma at the Northern Ireland Plastic Surgery Unit from August 2015 to March 2020. Patients were identified from theatre records and a prospectively collected sentinel lymph node database. The NI Multiple Deprivation Measure 2017 was used to measure SES. Results 440 patients were included (F = 54%, M = 46%). Mean age=63 (M = 67, F = 59). Mean Breslow Depth (BD) = 2.61mm (Range 0.17 – 27mm). Females had significantly thinner tumours at presentation (mean BD 2.16mm. vs 3.1mm in males, p = 0.001). In males the commonest sites were head and neck (36%) and back (23%). In females, the commonest sites were lower limb (42%) and upper limb (23%). There was a positive correlation between higher SES and increased incidence of melanoma (correlation coefficient (CC) 0.922), but this did not correlate with an increase in Breslow depth (CC -0.020). Conclusions This study provides important information on melanoma in NI, including gender and site variances. Females were more commonly affected and were a mean of 8 years younger than males at diagnosis but presented with significantly thinner tumours. Unlike the rest of the UK, the commonest site in males was the head and neck. Higher SES was related to higher incidence of melanoma but with presentation at an earlier stage of disease.