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Acral melanoma is a clinical subtype of melanoma with high mortality, on which research is limited in scope. This study aimed to assess incidence trends and melanoma-specific survival rates for acral melanoma in the Swedish population from 1990 to 2020.This cross-sectional study included patients with an acral melanoma diagnosis from 1990 to 2020 from the nationwide, population-based Swedish Melanoma Registry. Analyses on acral melanoma melanoma-specific survival rates were adjusted for age, sex, histopathological subtype, and tumour thickness. Clinicopathological features and melanoma-specific survival rates were compared between diagnostic periods: 1990-1999, 2000-2009, and 2010-2020, respectively. Changes in standardized incidence rates in 1996-2020 were evaluated separately for males and females. In total, 1,000 acral melanomas in 999 patients were included in the study. No significant yearly change in standardized incidence rates for either males or females was observed, even though the absolute number of cases increased. Factors such as male sex, age ≥ 70 years, and Breslow thickness > 1.0 were independently linked to lower melanoma-specific survival. The 5-year melanoma-specific survival across the studied period ranged from 75.8% to 77.9% for females, and from 62.4% to 71.7% for males.
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Melanoma , Sistema de Registros , Neoplasias Cutáneas , Humanos , Melanoma/mortalidad , Melanoma/epidemiología , Melanoma/patología , Masculino , Femenino , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/patología , Incidencia , Suecia/epidemiología , Anciano , Persona de Mediana Edad , Estudios Transversales , Adulto , Factores de Tiempo , Anciano de 80 o más Años , Tasa de Supervivencia , Factores de Riesgo , Adulto Joven , Distribución por Sexo , Adolescente , Distribución por Edad , Factores SexualesRESUMEN
Importance: Patients with melanoma are selected for sentinel lymph node biopsy (SLNB) based on their risk of a positive SLN. To improve selection, the Memorial Sloan Kettering Cancer Center (MSKCC) and Melanoma Institute Australia (MIA) developed predictive models, but the utility of these models remains to be tested. Objective: To determine the clinical utility of the MIA and MSKCC models. Design, Setting, and Participants: This was a population-based comparative effectiveness research study including 10â¯089 consecutive patients with cutaneous melanoma undergoing SLNB from the Swedish Melanoma Registry from January 2007 to December 2021. Data were analyzed from May to August 2023. Main Outcomes and Measures,: The predicted probability of SLN positivity was calculated using the MSKCC model and a limited MIA model (using mitotic rate as absent/present instead of count/mm2 and excluding the optional variable lymphovascular invasion) for each patient. The operating characteristics of the models were assessed and compared. The clinical utility of each model was assessed using decision curve analysis and compared with a strategy of performing SLNB on all patients. Results: Among 10â¯089 included patients, the median (IQR) age was 64.0 (52.0-73.0) years, and 5340 (52.9%) were male. The median Breslow thickness was 1.8 mm, and 1802 patients (17.9%) had a positive SLN. Both models were well calibrated across the full range of predicted probabilities and had similar external area under the receiver operating characteristic curves (AUC; MSKCC: 70.8%; 95% CI, 69.5-72.1 and limited MIA: 69.7%; 95% CI, 68.4-71.1). At a risk threshold of 5%, decision curve analysis indicated no added net benefit for either model compared to performing SLNB for all patients. At risk thresholds of 10% or higher, both models added net benefit compared to SLNB for all patients. The greatest benefit was observed in patients with T2 melanomas using a threshold of 10%; in that setting, the use of the nomograms led to a net reduction of 8 avoidable SLNBs per 100 patients for the MSKCC nomogram and 7 per 100 patients for the limited MIA nomogram compared to a strategy of SLNB for all. Conclusions and Relevance: This study confirmed the statistical performance of both the MSKCC and limited MIA models in a large, nationally representative data set. However, decision curve analysis demonstrated that using the models only improved selection for SLNB compared to biopsy in all patients when a risk threshold of at least 7% was used, with the greatest benefit seen for T2 melanomas at a threshold of 10%. Care should be taken when using these nomograms to guide selection for SLNB at the lowest thresholds.
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Melanoma , Ganglio Linfático Centinela , Neoplasias Cutáneas , Masculino , Humanos , Persona de Mediana Edad , Anciano , Femenino , Biopsia del Ganglio Linfático Centinela , AustraliaRESUMEN
Background: The incidence of melanoma in situ (MIS) is increasing even more rapidly than the incidence of cutaneous malignant melanoma (CMM). No previous studies have in detail investigated the survival in individuals diagnosed with MIS compared to the general population. Methods: This population-based study included individuals with MIS diagnosed in Sweden between 2001 and 2010 and randomly selected MIS-free comparators matched on age, sex and county of residence. Exclusion criterion was a previous CMM. Data on socioeconomic status (SES) including educational level, income and marital status, comorbidity and cause of death were obtained from population-based registers. Overall survival (OS) was estimated by the Kaplan-Meier method. The mortality risk adjusted for SES and comorbidity was assessed by multivariable Cox regression analyses. Findings: The survival analyses included 7963 cases and 39,662 comparators. Median age at MIS diagnosis were 63 (IQR 50-75) and 67 (IQR 57-76) years in women and men respectively. Median follow-up time was 120 months (IQR 102-152 months). In individuals with MIS, the ten-year OS was 77% (95% CI 0.76-0.78) compared to 72% (95% CI 0.72-0.73) in comparators. The MIS patients had a higher SES and lower comorbidity burden than the comparators. In a fully adjusted multivariable analysis, including 7772 cases and 38,103 comparators, the mortality was significantly lower in women with MIS (HR 0.88, 95% CI 0.82-0.94) compared to the background population. The corresponding estimate in men was HR 0.94 (95% CI 0.88-1.0). The risk of melanoma-related deaths during the study period was ten-fold higher in MIS patients. Interpretation: Despite being at increased risk of developing CMM, MIS patients had a better OS compared to their matched comparators from the background population, findings which could not fully be explained by differences in SES and comorbidity. Our results are reassuring and should be communicated to patients who have been diagnosed with MIS. Funding: Stiftelsen Onkologiska Klinikens i Uppsala Forskningsfond, Mats and Stefan Paulsson Trust, Medicon Village, Lund and Uppsala University Hospital (ALF).
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BACKGROUND: The key prognostic factors for staging patients with primary cutaneous melanoma are Breslow thickness, ulceration, and sentinel lymph node (SLN) status. The multicenter selective lymphadenectomy trial (MSLT-I) verified SLN status as the most important prognostic factor for patients with intermediate-thickness melanoma (Breslow thickness, 1-4 mm). Although most international guidelines recommend SLN biopsy (SLNB) also for patients with thick (> 4 mm, pT4) melanomas, its prognostic role has been questioned. The primary aim of this study was to establish whether SLN status is prognostic in T4 melanoma tumors. METHODS: Data for all patients with a diagnosis of primary invasive cutaneous melanoma of Breslow thickness greater than 1 mm in Sweden between 2007 and 2020 were retrieved from the Swedish Melanoma Registry, a large prospective population-based registry. A multivariable Cox proportional hazard model for melanoma-specific survival (MSS) was constructed based on Breslow thickness stratified for SLN status. RESULTS: The study enrolled 10,491 patients, 1943 of whom had a Breslow thickness greater than 4 mm (pT4). A positive SLN was found for 34% of these pT4 patients. The 5-year MSS was 71%, and the 10-year MSS was 62%. There was a statistically significant difference in MSS between the patients with a positive SLN and those with a negative SLN (hazard ratio of 2.4 (95% confidence interval CI 1.6-3.5) for stage T4a and 2.0 (95% CI 1.6-2.5) for satage T4b. CONCLUSION: Sentinel lymph node status gives important prognostic information also for patients with thick (> 4 mm) melanomas, and the authors thus recommend that clinical guidelines be updated to reflect this.
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Linfadenopatía , Melanoma , Ganglio Linfático Centinela , Neoplasias Cutáneas , Humanos , Melanoma/patología , Neoplasias Cutáneas/patología , Ganglio Linfático Centinela/patología , Pronóstico , Estudios Prospectivos , Biopsia del Ganglio Linfático Centinela , Linfadenopatía/cirugía , Ganglios Linfáticos/patología , Melanoma Cutáneo MalignoRESUMEN
INTRODUCTION: The prognosis for patients with melanoma has improved due to better treatments in recent years and updated tools to accurately predict an individual's risk are warranted. This study aims to describe a prognostic instrument for patients with cutaneous melanoma and its potential as a clinical device for treatment decisions. METHODS: Patients with localised invasive cutaneous melanoma diagnosed in 1990-2021 with data on tumour thickness were identified from the population-based Swedish Melanoma Registry. The parametric Royston-Parmar (RP) method was used to estimate melanoma-specific survival (MSS) probabilities. Separate models were constructed for patients (≤1 mm) and (>1 mm) and prognostic groups were created based on all combinations of age, sex, tumour site, tumour thickness, absence/presence of ulceration, histopathologic type, Clark's level of invasion, mitoses and sentinel lymph node (SLN) status. RESULTS: In total, 72 616 patients were identified, 41 764 with melanoma ≤1 mm and 30 852 with melanoma >1 mm. The most important variable was tumour thickness for both (≤1 mm) and (>1 mm), that explained more than 50% of the survival. The second most important variables were mitoses (≤1 mm) and SLN status (>1 mm). The prognostic instrument successfully created probabilities for >30 000 prognostic groups. CONCLUSIONS: The Swedish updated population-based prognostic instrument, predicts MSS survival up to 10 years after diagnosis. The prognostic instrument gives more representative and up-to-date prognostic information for Swedish patients with primary melanoma than the present AJCC staging. Additional to clinical use and the adjuvant setting, the information retrieved could be used to plan future studies.
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Linfadenopatía , Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/patología , Neoplasias Cutáneas/patología , Pronóstico , Suecia/epidemiología , Biopsia del Ganglio Linfático Centinela , Linfadenopatía/patología , Estadificación de Neoplasias , Melanoma Cutáneo MalignoRESUMEN
BACKGROUND: Melanoma-specific survival (MSS) is heterogenous between stages and is highly dependent on the T stage for primary localized disease. New systemic therapies for metastatic cutaneous melanoma (CM) have been introduced since 2012 in Sweden. OBJECTIVES: To analyse the incidence and MSS time trends between 1990 and 2020 in Sweden. METHODS: Nationwide, population-based and prospectively collected clinico-pathological data on invasive CM from the Swedish Melanoma Registry (SweMR) were analysed for survival trends between 1990 and 2020 using Kaplan-Meier curves and Cox proportional hazard ratios (HRs). RESULTS: In total, 77 036 primary invasive CMs were diagnosed in 70 511 patients in Sweden between 1990 and 2020. The 5-year MSS [95% confidence interval (CI)] was 88.9% (88.3-89.4) for 1990-2000, 89.2% (88.7-89.6) for 2001-2010 and 93.0% (92.7-93.9) for 2011-2020. The odds ratios for being diagnosed with nodular melanoma (vs. superficial spreading melanoma) was significantly reduced by 20% (2001-2010) and by 46% (2011-2020) vs. the reference period 1990-2000. Overall, the MSS improved over both diagnostic periods (2001-2010 and 2011-2020) vs. the reference period 1990-2000 among men and women, respectively [HRmen: 2001-2010: 0.89 (95% CI 0.82-0.96) and 2011-2020: 0.62 (95% CI 0.56-0.67); HRwomen: 2001-2010: 0.82 (95% CI 0.74-0.91) and 2011-2020: 0.62 (95% CI 0.56-0.70)]. The risk of death from CM was significantly lower in all age groups for both men and women in the most recent diagnostic period (2011-2020 vs.1990-2000). CONCLUSIONS: The results emphasize the improved MSS among men and women in Sweden. The MSS improvements, specifically for the period 2011-2020, may be correlated to the introduction of new systemic therapies and are here shown for the first time in detail for Sweden.
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Melanoma , Neoplasias Cutáneas , Masculino , Humanos , Femenino , Neoplasias Cutáneas/patología , Suecia/epidemiología , Incidencia , Pronóstico , Melanoma Cutáneo MalignoRESUMEN
BACKGROUND: Adjuvant treatments with PD-1 and BRAF+MEK inhibitors statistically significantly prolong recurrence-free survival in stage III cutaneous melanoma. Yet, the effect on overall survival is still unclear. Based on recurrence-free survival outcomes, these treatments have been approved and widely implemented. The treatments have considerable side effects and costs, and overall survival effect remains a highly anticipated outcome. METHODS: Clinical and histopathological parameters were obtained from the Swedish Melanoma Registry for patients diagnosed with stage III melanoma between 2016 and 2020. The patients were divided depending on if they were diagnosed before or from July 2018, based on the timepoint when adjuvant treatment was introduced in Sweden. Patients were followed up until the end of 2021. In this cohort study, melanoma-specific and overall survival were calculated using the Kaplan-Meier method and Cox-regression analyses. RESULTS: There were 1371 patients diagnosed with stage III primary melanoma in Sweden in 2016-2020. The 2-year overall survival rates, comparing the 634 patients in the precohort and the 737 in the postcohort, were 84.3% (95% confidence interval [CI] = 81.4% to 87.3%) and 86.1% (95% CI = 83.4% to 89.0%), respectively, with an adjusted hazard ratio of 0.91 (95% CI = 0.70 to 1.19, P = .51). Further, no statistically significant overall or melanoma-specific survival differences were seen when comparing the precohort and the postcohort in different subgroups for age, sex, or tumor characteristics. CONCLUSIONS: In this nationwide population-based and registry-based study, no survival benefit was detected in patients diagnosed before or after the implementation of adjuvant treatment in stage III melanoma. These findings encourage a careful assessment of the current recommendations on adjuvant treatment.
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Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Estudios de Cohortes , Adyuvantes Inmunológicos , Sistema de Registros , Estadificación de Neoplasias , Melanoma Cutáneo MalignoRESUMEN
PURPOSE: Few studies have focused on the late adverse events after oncologic treatment in pelvic cancer patients. Here, the treatment effect/interventions were studied on late side effects as GI, sexual, and urinary symptoms in pelvic cancer patients who visited a highly specialized rehabilitation clinic in Linköping. METHODS: This retrospective longitudinal cohort study included 90 patients who had at least one visit at the rehabilitation clinic for late adverse events at Linköping University hospital between 2013 to 2019. The toxicity of the adverse events was analyzed by using the common terminology criteria for adverse events (CTCAE). RESULTS: By comparing the toxicity of symptoms between visits 1 and 2, we showed that the GI symptoms decreased with 36.6% (P = 0.013), the sexual symptoms with 18.3% (P < 0.0001), and urinary symptoms with 15.5% (P = 0.004). Patients who received bile salt sequestrant had a significant improvement in grade of GI symptoms as diarrhea/fecal incontinence at visit 2 compared to visit 1 where 91.3% were shown to have a treatment effect (P = 0.0034). The sexual symptoms (vaginal dryness/pain) significantly improved due to local estrogens between visits 1 and 2 where 58.1% had a reduction of symptoms (P = 0.0026). CONCLUSION: The late side effects as GI, sexual, and urinary symptoms was significantly reduced between visits 1 and 2 at the specialized rehabilitation center in Linköping. Bile salt sequestrants and local estrogens are effective treatments for side effects as diarrhea and vaginal dryness/pain.
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Neoplasias Pélvicas , Enfermedades Vaginales , Femenino , Humanos , Neoplasias Pélvicas/terapia , Estudios Longitudinales , Estudios Retrospectivos , Diarrea , Dolor , Ácidos y Sales BiliaresRESUMEN
BACKGROUND: Comprehensible, relevant information empowers patients, allowing them to take an active part in their care. We aim to investigate how Swedish melanoma patients perceive information provided in routine clinical practice and explore the correlation between satisfaction with information, symptoms and functioning scales, and quality of life. METHODS: A cross-sectional study where EORTC QLQ-C30, EORTC QLQ-INFO25 and EQ-5D-3L questionnaires were sent to 1213 patients by post and 792 responded (65%). RESULTS: Only 0.5% reported that they wished to have received less information. The amount of information received and the satisfaction with that information was age-dependent, where older patients reported receiving less information than younger patients. Middle-aged patients were more satisfied with the information compared to both younger and older patients. The perception of having received sufficient information correlated negatively with anxiety. Higher satisfaction with the information also correlated positively with scores for functioning scales and negatively with degree of symptoms. No difference was perceived in information levels between disease stage apart from the scale "information about other services", where patients with more severe disease reported receiving more information. Men and women reported equal satisfaction concerning the information received. CONCLUSIONS: Patients lack sufficient information and age affects the perception of it. It is of utmost importance to tailor the information to suit the individual needs of a given patient, as satisfaction with the information received correlates with the patient's well-being.
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Melanoma/psicología , Aceptación de la Atención de Salud/psicología , Educación del Paciente como Asunto/estadística & datos numéricos , Satisfacción del Paciente/estadística & datos numéricos , Factores de Edad , Anciano , Ansiedad , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Percepción , Pautas de la Práctica en Medicina , Calidad de Vida , Encuestas y Cuestionarios , SueciaRESUMEN
BACKGROUND: The incidence of invasive cutaneous melanoma (CM) is increasing in Sweden. The aim was to present age- and sex-specific trends of the age-standardised incidence and the average annual percentage change (AAPC) for in situ and invasive CM. METHODS: Joinpoint regression models were used to analyse data from the Swedish Cancer Register and the Swedish Melanoma Registry 1997-2018 (N = 35,350 in situ CM; 59,932 CM). RESULTS: The AAPC of CM for women was 4.5 (4.1-5.0; p < 0.001) for the period 1997-2018. For men, the APCC was 4.2 (3.0-5.4; p < 0.001), with a significantly higher annual percentage change (APC) for the period 2000-2018 (5.0; 4.6-5.4; p < 0.001) compared to 1997-1999. An increasing annual incidence of CM ≤ 0.6 mm and 0.7 mm Breslow tumour thickness was found for men with a significant incidence shift for the period 2006-2015, respectively. Similarly for women, with a significantly higher APC for CM ≤ 0.6 mm from 2005. The incidence of intermediate thick CM (2.1-4.0 mm) has not increased since 2011. The incidence of CM > 4.0 mm has been increasing among both sexes, with a significantly lower APC among women from 2005. CONCLUSIONS: The incidence of in situ and low-risk CM ≤ 1.0 mm in tumour thickness has been rising among both sexes since the 2000s.
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Previous studies have demonstrated an anti-tumoral effect of beta-adrenergic blocking agents on cutaneous melanoma (CM). The aim of this study was to investigate if beta-adrenergic blocking agents have an impact on survival in Swedish patients with melanoma. A population-based retrospective registry study including all patients diagnosed with a primary invasive melanoma between 2009 and 2013 was performed. Data from the Swedish Melanoma Register were linked to the Swedish Prescribed Drug Registry and the Swedish Cause of Death Register. Cox regression analyses including competing risk assessments were performed. There were 12,738 patients included, out of which 3702 were exposed to beta-blockers vs. 9036 non-exposed patients. Age, male sex, Breslow thickness, ulceration, and nodal status were independent negative prognostic factors for melanoma-specific survival (MSS). Adding beta-blockers to the analysis did not add any prognostic value to the model (HR 1.00, p = 0.98), neither when adjusting for competing risks (HR 0.97, p = 0.61). When specifically analyzing the use of non-selective beta-blockers, the results were still without statistical significance (HR 0.76, p = 0.21). In conclusion, this population-based registry study could not verify that the use of beta-adrenergic blocking agents improve survival in patients with melanoma.
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We thank De Giorgi et al for their interest in our study, and for raising important and relevant questions [...].
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BACKGROUND: Cutaneous melanoma is steadily increasing worldwide. The new AJCC 8th edition was recently launched and introduced several changes in melanoma staging, particularly for stage III. We conducted a population-based registry study with the purpose to evaluate the impact and prognostic accuracy of the new classification in Sweden. METHODS: Consecutive patients diagnosed with stage III melanoma between January 2005 and September 2017 were identified by the Swedish Melanoma Registry (SMR) and included for analyses. Patients with multiple primary melanomas were excluded. Patients were classified according to the AJCC 7th as well as the 8th edition. Melanoma-specific survival (MSS) was retrieved from the Swedish Cause of Death Registry. RESULTS: A total of 2067 eligible patients were identified from the SMR; 1150 patients (57%) changed stage III subgroup when reclassified according to the AJCC 8th edition. The median 5- and 10-year MSS for the whole cohort of stage III melanoma patients was 59% and 51% respectively. The MSS for substage IIIA, B, and C were all improved when patients were reclassified by using to the AJCC 8th edition. The newly defined substage IIID had the worst prognosis with a 10-year MSS of 16%. CONCLUSIONS: A high proportion of patients diagnosed with stage III melanoma in Sweden between 2005 and 2017 was restaged to another subgroup, when they were reclassified according to the AJCC 8th of staging manual. We established an improved MSS for all substages compared with the former AJCC 7th edition. This may have implications on decisions about adjuvant treatment.
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Melanoma/epidemiología , Melanoma/patología , Estadificación de Neoplasias/normas , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/patología , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Melanoma/clasificación , Persona de Mediana Edad , Sistema de Registros , Neoplasias Cutáneas/clasificación , Tasa de Supervivencia , Suecia/epidemiología , Melanoma Cutáneo MalignoRESUMEN
INTRODUCTION: Our primary objective was to test the hypothesis that human epididymal protein 4 (HE4) and risk of ovarian malignancy index outperform the CA 125 and risk of malignancy index tests in categorizing a pelvic mass into high or low risk of malignancy in a Swedish population. Furthermore, cut-off values needed to be defined for HE4 and ROMA in premenopausal and postmenopausal women prior to their introduction to clinical practice. A third objective was to investigate the correlation between HE4 levels in serum and urine. MATERIAL AND METHODS: Women with a pelvic mass scheduled for surgery were recruited from nine hospitals in south-east Sweden. Preoperative blood samples were taken for analyzing CA125 and HE4 as well as urine samples for analyzing HE4. RESULTS: We enrolled a total of 901 women, of whom 784 were evaluable. In the premenopausal and postmenopausal groups, no significant differences were found for sensitivity, positive and negative predictive value, either for RMI vs ROMA or for CA125 vs HE4 using a fixed specificity of 75%. Cut-off values indicating malignancy were established for HE4 and ROMA in premenopausal and postmenopausal women. We found no correlation between HE4 concentration in serum and urine. CONCLUSIONS: We could not confirm that ROMA had diagnostic superiority over RMI in categorizing women with a pelvic mass into low-risk or high-risk groups for malignancy in a Swedish population. We have defined cut-off values for HE4 and ROMA. The lack of correlation between serum and urine HE4 obviates the introduction of urine HE4 analysis in clinical diagnostics.
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Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/orina , Antígeno Ca-125/sangre , Neoplasias Ováricas/sangre , Neoplasias Ováricas/orina , Proteínas/metabolismo , Adulto , Algoritmos , Técnicas de Apoyo para la Decisión , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Suecia , Proteína 2 de Dominio del Núcleo de Cuatro Disulfuros WAPRESUMEN
BACKGROUND: Sentinel lymph node (SLN) metastasis in patients with thin melanomas (≤1 mm) is uncommon but adverse prognostic factors may indicate an increased risk. We sought to determine how often SLN biopsy (SLNB) was performed in patients with thin melanomas, establish the frequency of SLN metastasis and evaluate the predictive value of ulceration, tumor mitotic rate, and thickness for SLN involvement. METHODS: Melanoma patients with a Breslow thickness greater than or equal to 0.5 to less than or equal to 1 mm, diagnosed 2009-2016, were identified in the Swedish Melanoma Register (SMR) and the Melanoma Institute Australia (MIA) Database. RESULTS: In total 8165 patients were included from the SMR and 1603 from MIA. SLNB was performed in 9.5% and 16.2% of patients, respectively. Corresponding figures for T1b (American Joint Committee on Cancer [AJCC] 7th Edition) were 19.5% and 24.6%. The SLN positivity rate were 4.4% (Sweden) and 5.8% (MIA). SLN metastasis was more frequent in tumors with ulceration, mitoses, and Breslow thickness greater than or equal to 0.9 mm but none were statistically significant. Younger age was identified as a significant risk factor for SLN positivity at MIA. CONCLUSIONS: A minority of patients with thin melanomas had SLNB performed and the SLN positivity rate was low. This study did not confirm tumor ulceration, mitoses, or thickness as statistically significant predictors for SLN metastasis.