The kinetics of the visible growth of a primary melanoma reflects the tumor aggressiveness and is an independent prognostic marker: a prospective study

Impact of the COVID-19 Pandemic on the Incidence and Thickness of Cutaneous Melanoma in Belgium

(1) Background: COVID-19 had a major impact on cancer diagnostics and treatment. Delays in diagnosis of cutaneous melanoma were particularly feared, given the impact on survival and morbidity that comes with advanced stages. Moreover, its incidence in Belgium has been rapidly increasing in recent decades. This Belgian population-level study quantifies the pandemic effect on the number of melanoma diagnoses and Breslow thickness in 2020 and 2021. (2) Methods: In using an automated algorithm, the number of cutaneous melanoma diagnoses and Breslow thickness were extracted from all pathology protocols from 2017-2021 by the Belgian Cancer Registry. Monthly variations, as well as year-to-year differences, were studied. (3) Results: Annual incidence of cutaneous melanoma fell by 1% in 2020, compared to 2019, mainly due to a diagnostic deficit in March, April, and May 2020. An 8% incidence increase occurred in 2021, primarily reflecting an increase in the number of the thinnest melanomas (≤1 mm). Both the mean and median Breslow thicknesses were higher in spring 2020, resulting from an underrepresentation of thinner tumors. However, no particulars stood out on a full-year basis in either 2020 or 2021. (4) Conclusions: Considering the expected incidence increase, we estimate almost 210 melanoma diagnoses were missed in Belgium in 2020, corresponding to 6% of the expected number. This deficit occurred mainly during the first COVID-19 wave. Despite some rebound, the 2021 total was still 3% short of the expected number, leaving around 325 diagnoses remaining pending in 2020 and 2021, corresponding to a two-year deficit of 4.35%. Fortunately, mainly thin melanomas were missed, without any detectable shift toward thicker tumors later in 2020 and or 2021.

[Translated article] Tumor Doubling Time in Skin Cancer: Can It Be Estimated and Is It Useful?

Skin cancer, like other cancers, is characterized by the uncontrolled growth of transformed cells. Tumor growth has been studied for decades. We review different methods for measuring skin tumor growth and propose a new system for estimating tumor doubling time that could be useful in the management of skin cancer.

Tumor Doubling Time in Skin Cancer: Can It Be Estimated and Is it Useful?

Skin cancer, like other cancers, is characterized by the uncontrolled growth of transformed cells. Tumor growth has been studied for decades. We review different methods for measuring skin tumor growth and propose a new system for estimating tumor doubling time that could be useful in the management of skin cancer.

Obstructive sleep apnoea is related to melanoma aggressiveness through paraspeckle protein-1 upregulation

BACKGROUND

In patients with obstructive sleep apnoea (OSA), intermittent hypoxia induces overexpression of paraspeckle component (PSPC)1, a master modulator of transforming growth factor (TGF)-β signalling, which promotes cell cancer progression through epithelial-mesenchymal transition (EMT) and acquisition of cancer stem cell (CSC)-like features. However, the persistence of intermittent hypoxia-induced effects on PSPC1, and their consequences in cancer patients are not known. To this effect, circulating PSPC1 levels were compared in patients with cutaneous melanoma with or without OSA, and their relationship with tumour aggressiveness along with the in vitro effects of soluble PSPC1 and intermittent hypoxia on melanoma cell aggressiveness mechanisms were assessed.

METHODS

In 292 cutaneous melanoma patients, sleep studies and serum levels of PSPC1 and TGF-β were evaluated. The effect of PSPC1 on expression of EMT and CSC transcription factors was assessed using melanoma cell lines with patient sera under both normoxia and intermittent hypoxia conditions.

RESULTS

PSPC1 levels were higher in patients with moderate-severe OSA compared with mild OSA or non-OSA patients. Serum levels of PSPC1 were associated with several cutaneous melanoma clinical aggressiveness indicators. Both intermittent hypoxia exposures and serum from OSA patients upregulated TGF-β expression and amplified the expression of transcription factors associated with EMT activation and acquisition of CSC characteristics.

CONCLUSION

In cutaneous melanoma patients, OSA severity is associated with higher PSPC1 serum levels, which jointly with intermittent hypoxia would enhance the self-reprogramming capabilities of EMT and CSC feature acquisition of melanoma cells, promoting their intrinsic aggressiveness.

Limited impact of COVID-19-related diagnostic delay on cutaneous melanoma and squamous cell carcinoma tumour characteristics: a nationwide pathology registry analysis

BACKGROUND

The COVID-19 pandemic reduced the number of skin cancer diagnoses, potentially causing a progression to unfavourable tumour stages.

OBJECTIVES

To identify the impact of delayed diagnostics on primary invasive melanoma and cutaneous squamous cell carcinoma (cSCC) by comparing tumour (pT) stage, Breslow thickness and invasion depth from before to after the first and second lockdown periods.

METHODS

In this population-based cohort study, histopathology reports registered between 1 January 2018 and 22 July 2021 were obtained from the nationwide histopathology registry in the Netherlands. The Breslow thickness of melanomas, invasion depth of cSCCs, and pT stage for both tumour types were compared across five time periods: (i) pre-COVID, (ii) first lockdown, (iii) between first and second lockdowns, (iv) second lockdown and (v) after second lockdown. Breslow thickness was compared using an independent t-test. pT-stage groups were compared using a χ2 -test. Outcomes were corrected for multiple testing using the false discovery rate.

RESULTS

In total, 20 434 primary invasive melanomas and 68 832 cSCCs were included in this study. The mean primary melanoma Breslow thickness of the prepandemic era (period i) and the following time periods (ii-v) showed no significant difference. A small shift was found towards unfavourable pT stages during the first lockdown compared with the pre-COVID period: pT1 52·3% vs. 58·6%, pT2 18·9% vs. 17·8%, pT3 13·2% vs. 11·0%, pT4 9·1% vs. 7·3% (P = 0·001). No relevant changes were seen in subsequent periods. No significant change in pT stage distribution was observed between the pre-COVID (i) and COVID-affected periods (ii-v) for cSCCs.

CONCLUSIONS

To date, the diagnostic delay caused by COVID-19 has not resulted in relatively more unfavourable primary tumour characteristics of melanoma or cSCC. Follow-up studies in the coming years are needed to identify a potential impact on staging distribution and survival in the long term.

Molecular characterization of fast-growing melanomas

BACKGROUND

The rate of growth of primary melanoma is a robust predictor of aggressiveness, but the mutational profile of fast-growing melanomas (FGMM) and the potential to stratify patients at high risk of death has not been comprehensively studied.

OBJECTIVE

To investigate the epidemiologic, clinical, and mutational profile of primary cutaneous melanomas with a thickness ≥ 1 mm, stratified by rate of growth.

METHODS

Observational prospective study. Deep-targeted sequencing of 40 melanoma driver genes on formalin fixed, paraffin-embedded primary melanoma samples. Comparison of FGMM (rate of growth > 0.5 mm/month) and nonFGMM (rate of growth ≤ 0.5 mm/month).

RESULTS

Two hundred patients were enrolled, among wom 70 had FGMM. The relapse-free survival was lower in the FGMM group (P = .014). FGMM had a higher number of predicted deleterious mutations within the 40 genes than nonFGMM (P = .033). Ulceration (P = .032), thickness (P = .006), lower sun exposure (P = .049), and fibroblast growth factor receptor 2 (FGFR2) mutations (P = .037) were significantly associated with fast growth.

LIMITATIONS

Single-center study, cohort size, potential memory bias, number of investigated genes.

CONCLUSION

Fast growth is linked to specific tumor biology and environmental factors. Ulceration, thickness, and FGFR2 mutations are associated with fast growth. Screening for FGFR2 mutations might provide an additional tool to better identify FGMM, which are probably good candidates for adjuvant therapies.

Speed rate (SR) as a new dynamic index of melanoma behavior

Melanomas are skin tumors that show a variety of biological behavior. Some develop very fast and some other grow extremely slow, with metastasis appearing, eventually, many years after the diagnosis. The number of mitoses in primary melanoma has been related to a more aggressive tumor and may have a potential as predictive factor for cutaneous melanoma survival. However, tumor mitotic rate is a static measure and in multivariate analysis on tumor survival, it has scored less than other tumor characteristics. We tried to evolve tumor mitotic rate from a static parameter to a time-dependent one. Similar to the already described growth rate (GR), we propose the speed rate (SR). SR is defined as the ratio of tumor mitotic rate to time to melanoma development. A prospective series of 345 patients with melanoma was investigated for the role of SR as predictive factor for sentinel lymph node (SLN) positivity and tumor progression. We calculated the best threshold for SR and GR to predict the risk of recurrence. Melanoma clinical and histological characteristics as well as GR were correlated in a multivariated analysis with SR. SR values >0.2 mitoses/month were associated with negative prognostic factors such as ulceration (82.8%), SLN positivity (80%), progression (82.8%), and death (85.7%). The association of GR > 0.3 mm/months and SR > 0.2 mitoses/month had a significant predictive value in terms of SLN positivity, progression, and recurrence-free survival. We propose SR as a new "dynamic" predictor of histological SLN positivity and melanoma recurrence risk. We think that he association with this new feature with GR may be helpful in improving the accuracy of predicted clinical outcome of patient especially with thin melanomas.

Tumor growth rate as a prognostic factor of acral melanoma in a Korean population

Rapid growth of cutaneous melanoma is associated with aggressive histopathologic features and poor prognosis. However, the impact of growth rate (GR) in acral melanoma (AM) remains largely unknown.We performed this study to identify the impact of GR on lymph node metastasis and survival in AM.We analyzed cases of invasive AM diagnosed at our institution between 1998 and 2017. We investigated the impact of GR on the prognosis of AM.A total of 126 cases of invasive AM were included. Log (GR) was significant associated with lymph node metastasis in the univariate logistic regression analysis (P = .005). The log-rank test revealed statistically significant differences in disease-free survival (DFS) and disease-specific survival (DSS) among the GR quartiles. In the Cox regression analysis, log (GR) was an independent predictor for DFS (P = .041), but not for DSS in multivariate analysis. In the subgroup analysis, log (GR) was an independent predictor for early-stage (≤2A) AM (DFS, P = .002; DSS, P = .004).The limitations of this study include the retrospective design of the study and possible recall bias.Our results suggest that GR is an important prognostic factor for DFS and DSS in AM patients and an independent predictor for early-stage AM.

Measuring the horizontal and vertical growth rates of superficial spreading melanoma: a pilot study with sequential digital dermoscopy

BACKGROUND

Some authors have hypothesized that the initial kinetics of the primary melanoma (MM) growth could reflect its biologic aggressiveness. The aim of this study was to pilot a measure of the horizontal vs. vertical growth of superficial spreading melanomas (SSM).

METHODS

The dermoscopic images of twenty-three consecutive MMs (17 SSMs and 6 MMs in situ), excised after digital sequential dermoscopy, were reviewed. We built up two indexes: 1) dROG (digital Rate of Growth) defined as Breslow thickness/(t1-tR), where t1 was the reported time of the first dermoscopic image acquisition and tR was the reported time of the acquisition before the lesion excision; 2) lHGR (linear Horizontal Growth Rate) took into account the greater axis of the lesion at two time points, at the time (t1) of the first image acquisition (D1) and before (tR) lesion excision (DR). The index was computed as (DR-D1)/(t1-tR). We built up the Composite Rate of Growth index (cROG) calculated as dROG/lHRG. If the value of cROG is <1 the superficial growth is prevalent on the vertical growth, and if the value is >1 the vertical growth is prevalent on the superficial growth.

RESULTS

In 82.6% of lesions the horizontal growth was prevalent on the vertical growth, and in 17.4% of cases the vertical growth was equal or prevalent on the superficial growth.

CONCLUSIONS

A small proportion of SSMs with a slow horizontal growth could have a precocious vertical growth. Other larger studies are needed to confirm this observation.

Clinicopathological predictors of recurrence in nodular and superficial spreading cutaneous melanoma: a multivariate analysis of 214 cases

BACKGROUND

Nodular melanoma (NM) accounts for most thick melanomas and because of their frequent association with ulceration, fast growth rate and high mitotic rate, contribute substantially to melanoma-related mortality. In a multicentric series of 214 primary melanomas including 96 NM and 118 superficial spreading melanoma (SSM), histopathological features were examined with the aim to identify clinicopathological predictors of recurrence.

METHODS

All consecutive cases of histopathologically diagnosed primary invasive SSM and NM during the period 2005-2010, were retrieved from the 12 participating Italian Melanoma Intergroup (IMI) centers. Each center provided clinico-pathological data such as gender, age at diagnosis, anatomical site, histopathological conventional parameters, date of excision and first melanoma recurrence.

RESULTS

Results showed that NM subtype was significantly associated with Breslow thickness (BT) at multivariate analysis: [BT 1.01-2 mm (OR 7.22; 95% CI 2.73-19.05), BT 2.01-4 mm (OR 7.04; 95% CI 2.54-19.56), and BT > 4 mm (OR 51.78; 95% CI 5.65-474.86) (p < 0.0001)]. Furthermore, mitotic rate (MR) was significantly correlated with NM histotype: [(MR 3-5 mitoses/mm2 (OR 2.62; 95% CI 1.01-6.83) and MR > 5 mitoses/mm2 (OR 4.87; 95% CI 1.77-13.40) (p = 0.002)]. The risk of recurrence was not significantly associated with NM histotype while BT [BT 1.01-2.00 mm (HR 1.55; 95% CI 0.51-4.71), BT 2.01-4.00 mm (HR 2.42; 95% CI 0.89-6.54), BT > 4.00 mm. (HR 3.13; 95% CI 0.95-10.28) (p = 0.05)], mitotic rate [MR > 2 mitoses/mm2 (HR 2.34; 95% CI, 1.11-4.97) (p = 0.03)] and the positivity of lymph node sentinel biopsy (SNLB) (HR 2.60; 95% CI 1.19-5.68) (p = 0.007) were significantly associated with an increased risk of recurrence at multivariate analysis.

CONCLUSIONS

We found that NM subtype was significantly associated with higher BT and MR but it was not a prognostic factor since it did not significantly correlate with melanoma recurrence rate. Conversely, increased BT and MR as well as SNLB positivity were significantly associated with a higher risk of melanoma recurrence.

An observational study regarding the rate of growth in vertical and radial growth phase superficial spreading melanomas

The natural history of superficial spreading melanomas (SSMs) involves the progression from a radial growth phase (RGP) to a vertical growth phase (VGP). Currently, a patient's history represents the only method to estimate the rate of tumor growth. The present study aimed to verify whether the estimated rate of growth (ROG) of SSMs with a RGP or VGP exhibited any differences, and to evaluate the possible implications for the most important prognostic determinants. ROG was quantified as the ratio between Breslow's thickness in millimeters (mm) and the time of tumor growth in months, defined as the time between the date that the patient had first noticed the lesion in which melanoma subsequently developed and the date on which the patient first felt this lesion changed. A total of 105 patients (58 male and 47 female) were studied. Of these, 66 had VGP-SSMs, whilst 39 had RGP-only SSMs (RGP-SSMs). No significant differences in age and gender were observed between these groups. The mean Breslow's thickness in patients with VGP-SSMs was significantly greater than in patients with RGP-SSMs (0.78±0.68 vs. 0.48±0.22 mm, P=0.0096). Similarly, the ROG was observed to be higher in VGP-SSM vs. RGP-SSM patients (0.13±0.16 vs. 0.065±0.09 mm/month, P=0.0244). In patients with VGP-SSMs, Breslow's thickness and ROG were significantly higher for tumors with a mitotic rate of ≥1 mitosis/mm² compared with those with <1 mitosis/mm² (1.15±0.96 vs. 0.56±0.30 mm, P=0.0005; and 0.188±0.20 vs. 0.09±0.12 mm/month, P=0.0228, respectively). According to these results, two subsets of SSMs exist: The first is characterized by the presence of mitosis and a higher ROG, while the second exhibits a more indolent behavior and is characterized by an RGP only. Given the differences in the Breslow's thickness and ROG, clinicians must be aware of the possible diagnostic delay in these subsets of melanoma that, differently from true nodular melanomas, generally fulfill the classical ABCD clinical criteria.

EMMPRIN/CD147 is an independent prognostic biomarker in cutaneous melanoma

CD147 has been implicated in melanoma invasion and metastasis mainly through increasing metalloproteinase synthesis and regulating VEGF/VEGFR signalling. In this study, the prognostic value of CD147 expression was investigated in a cohort of 196 cutaneous melanomas including 136 consecutive primary malignant melanomas, 30 lymph nodes, 16 in-transit and 14 visceral metastases. A series of 10 normal skin, 10 blue nevi and 10 dermal nevi was used as control. CD147 expression was assessed by immunohistochemistry, and the association of its expression with the clinicopathological characteristics of patients and survival was evaluated using univariate and multivariate statistical analyses. Univariate analysis showed that high CD147 expression was significantly associated with metastatic potential and with a reduced overall survival (P < 0.05 for both) in primary melanoma patients. CD147 expression level was correlated with histological factors which were associated with prognosis: Clark level, ulceration status and more particularly with Breslow index (r = 0.7, P < 10(-8) ). Multivariate analysis retained CD147 expression level and ulceration status as predicting factors for metastasis and overall survival (P < 0.05 for both). CD147 emerges as an important factor in the aggressive behaviour of melanoma and deserves further evaluation as an independent prognostic biomarker.

Melanoma burden by melanoma stage: Assessment through a disease transition model

BACKGROUND

The total burden of melanoma has already been studied but little is known about the distribution of this burden amongst localised, node metastatic and distant metastatic stages.

METHODS

Disability-adjusted life years (DALY) assesses disease burden, being the sum of years of life with disability (YLD) and years of life lost (YLL). A melanoma disease model was developed in order to predict the evolution of patients from diagnosis until death. The model was applied to a large cohort of 8016 melanoma patients recorded by the Belgian Cancer Registry for incidence years 2009-2011. DALYs were calculated for each American Joint Committee on Cancer stage, considering stage at diagnosis on the one hand and time spent in localised, node metastatic and visceral metastatic stages on the other. Probabilistic sensitivity analyses and scenario analyses were performed to explore uncertainty.

FINDINGS

Our analyses resulted in 3.67 DALYs per melanoma, 90.81 per 100,000 inhabitants, or 32.67 per death due to melanoma. The total YLL accounted for 80.4% of the total DALY. Stages I, II, III and IV patients at diagnosis generated, respectively, 27.8%, 32.7%, 26.2% and 13.3% of the total YLL. For the time spent in each stage, localised melanomas, node metastatic melanomas, and distant metastatic accounted, respectively, for 34.8%, 52.6% and 12.6% of the total YLD. Parametric uncertainty was very limited, but the influence of using pre-2010 Global Burden of Disease approaches was substantial.

INTERPRETATION

The total DALY for melanoma was consistent with the previous studies. Our results in terms of proportions of DALY/YLL/YLD per stage could be extrapolated to other high-income countries. YLDs generated by localised melanoma which will never metastasize were inferior to YLLs resulting from stage IA melanomas. This result supports the hypothesis that efforts for an earlier diagnosis of melanoma are important.

FUNDING

None.

The role of BRAF mutations in primary melanoma growth rate and survival

BACKGROUND

The clinical behaviour and prognosis of primary melanomas harbouring BRAF mutations is not fully understood.

OBJECTIVES

To investigate the effect of mutation status on primary melanoma growth rate and melanoma-specific survival (MSS).

METHODS

A prospective cohort of 196 patients with stage I-III primary cutaneous melanoma were followed for a median of 92 months, pre-dating the institution of BRAF inhibitor therapy. Clinicopathological variables were correlated with mutation status and hazard ratios (HRs) estimated for MSS.

RESULTS

Of 196 tumours, 77 (39.2%) were BRAF V600E, 10 (5.1%) BRAF V600K and 33 (16.8%) were NRAS mutant. BRAF V600E mutant melanomas were associated with favourable clinical characteristics and tended to be slower growing compared with BRAF V600K, NRAS mutant or BRAF/NRAS wild-type tumours (0.12 mm per month, 0.61 mm per month, 0.36 mm per month and 0.23 mm per month, respectively; P = 0.05). There were 39 melanoma deaths, and BRAF mutant melanomas were associated with poorer MSS in stage I-III disease [HR 2.60, 95% confidence interval (CI) 1.20-5.63; P = 0.02] and stage I-II disease (HR 3.39, 95% CI 1.12-10.22; P = 0.03) after adjusting for other prognostic variables. Considered separately, BRAF V600E mutant melanomas were strongly associated with MSS independently of thickness and nodal status (HR 3.89, 95% CI 1.67-9.09; P < 0.01) but BRAF V600K mutant tumours were not (HR 1.19, 95% CI 0.36-3.92; P = 0.77).

CONCLUSIONS

The presence of a BRAF mutation does not necessarily 'drive' more rapid tumour growth but is associated with poorer MSS in patients with early-stage disease.

Defining the dermoscopic characteristics of fast-growing cutaneous melanomas

A high growth rate in melanomas has been associated with a more aggressive phenotype and worse survival. The aim of this study was to define the dermoscopic characteristics associated with this type of cutaneous melanoma. We carried out a retrospective study of 132 cutaneous melanomas, analyzing certain clinical characteristics and the most important dermoscopic variables related to the melanomas. Fast-growing melanomas were considered to be those with a growth rate of more than 0.5 mm per month. Fast-growing melanomas more often lacked an atypical network, were symmetrical, presented ulceration, and were hypopigmented. The dermoscopic vascular pattern often showed atypical irregular vessels and milky-red areas. The association of these two is a specific characteristic. Fast-growing melanomas have a characteristic phenotype and dermoscopy can be useful for their identification.

Efficacy of a general practitioner training campaign for early detection of melanoma in France

BACKGROUND

To date, no strategy for improving early diagnosis of melanoma has been evaluated on a population basis in France.

OBJECTIVE

To evaluate the efficacy of a general practitioner (GP) awareness and training campaign in a pilot French geographical region (Champagne-Ardenne), including 1.34 million inhabitants, 1241 GPs, 56 dermatologists and a population-based melanoma registry.

METHODS

All GPs received repeated awareness postal mailings in 2008 and 398 (32.1%) attended training sessions organized by 27 dermatologists. The pre- (2005-7) and post-campaign (2009-11) periods were compared for the following: primary endpoint - the world-standardized incidence of very thick melanomas (VTM) (Breslow thickness ≥ 3 mm); secondary endpoints--the mean Breslow thickness; the proportions of VTM and of thin (< 1 mm) melanomas among invasive cases; and the ratio of in situ/all melanoma cases. Similar measures were performed in the control area of Doubs/Belfort territory (655,000 ha), where no similar campaign was carried out.

RESULTS

The incidence of VTM decreased from 1.07 to 0.71 per 100 000 habitants per year (P = 0.01), the mean Breslow thickness from 1.95 to 1.68 mm (P = 0.06) and the proportion of VTM from 19.2% to 12.8% (P = 0.01). The proportion of thin and in situ melanomas increased from 50.9% to 57.4% (P = 0.05) and from 20.1% to 28.2% (P = 0.001), respectively. No significant variation was observed in Doubs/Belfort territory.

CONCLUSION

These results strongly support the efficacy of such a campaign targeting GPs and provide a rationale for a larger public health campaign in France, including training of GPs by dermatologists and encouraging patients to ask their GP for a systematic skin examination.

Nodular melanoma: five consecutive cases in a general practice with polarized and non-polarized dermatoscopy and dermatopathology

Background:

The incidence of nodular melanoma (NM) has been consistently described as at least 10–15% of total melanomas for over 15 years despite advances in diagnostic algorithms and medical technology. NMs are strongly correlated with faster rates of growth and poorer prognosis and thus provide clinicians with a challenge for early recognition.

Objective:

To evaluate diagnostic clues of consecutive histopathologically proven NMs in one general practice with particular emphasis on dermatoscopic characteristics and compare this to the published literature.

Method:

A retrospective observational study was performed of five consecutive histologically proven NM, from a total of 212 consecutive melanomas from a general practice in Brisbane, Queensland, Australia. Dermatoscopic images, both polarized and non-polarized, which appears to be a unique resource, and dermatopathologic slides were available for all lesions.

Results:

All of the NMs in this series were pigmented although one was hypomelanotic. Two of them were symmetrical. The most highly sensitive clues to NM were gray or blue structures and polarizing-specific white lines.

Limitations:

Due to the small number of NMs in this report no statistical significance can be attributed to the observational findings.

Conclusion:

This small series supports what is already known: that a significant proportion of NMs may be dermatoscopically symmetrical but that known clues to melanoma are frequently present. Nodular lesions, pigmented or non-pigmented, should be excised to exclude NM if there is any clue to malignancy, regardless of symmetry, unless a confident specific benign diagnosis can be made.

Chronology of metastasis in cutaneous melanoma: growth rate model

In humans, it is not possible to obtain experimental evidence of when a cancer begins to metastasize. The purpose of this study was to estimate the time of onset of metastatic dissemination in cutaneous melanoma using a model based on its growth rate (GR). The critical time of onset of metastatic dissemination below which no cases of fatal melanomas were seen may be described with a potential function in which this time is inversely proportional to the GR. The critical time of development beyond which a melanoma may metastasize presents great variation. This time was just 1 month for those melanomas with a fast GR, whereas it was over 5 years for those with a very slow GR. Quantitatively, the fastest-growing melanomas began metastasizing with a greater thickness than the slowest-growing melanomas. A correlation exists between the critical time of onset of metastatic potential and the GR of the melanoma. These results may well have relevance to the understanding of mechanisms of tumor dissemination and for the design of future studies on melanomas, irrespective of whether they are basic studies on biomolecular mechamisms or clinical studies.

Melanoma update: diagnostic and prognostic factors that can effectively shape and personalize management

Routine light microscopy remains a powerful tool to diagnose, stage and prognose melanoma. Although it is very economical and efficient, it requires a significant level of expertise and, in difficult cases the final diagnosis is affected by subjective interpretation. Fortunately, new insights into the genomic aberrations characteristic of melanoma, coupled with ancillary studies, are further refining evaluation and management allowing for more confident diagnosis, more accurate staging and the selection of targeted therapy. In this article, we review the standard of care and new updates including four probe FISH, the 2009 American Joint Commission on Cancer staging of melanoma and mutant testing of melanoma, which will be crucial for targeted therapy of metastatic melanoma.

Growth rate of melanoma in vivo and correlation with dermatoscopic and dermatopathologic findings

OBJECTIVES

The aim of this study was to calculate the horizontal growth rate of melanoma in vivo and to correlate it with morphologic findings.

PATIENTS AND METHODS

We searched our database for melanomas for which sequential dermatoscopic images and histopathologic slides were available. The final sample consisted of 50 melanomas of 48 patients (mean age: 50 ± 15 years, 62% females). We calculated the horizontal growth rate in mm(2) per year by morphometric analysis of digital dermatoscopic images. Dermatoscopic and dermatopathologic findings were assessed according to predefined criteria and correlated with the horizontal growth rate.

RESULTS

The median time interval between baseline and follow-up image was 12 months (range: 2-100 months). The majority of melanomas were in situ (n=28, 56%). The mean horizontal growth rate of all melanomas was 5.3 mm(2)/year (SD: ± 5.8 mm(2)/year). The histopathologic findings of numerous and large epidermal nests were associated with rapid growth. This histopathologic pattern corresponded to a pattern of clods ("globules") dermatoscopically. From a dermatoscopic point of view, melanomas with a main pattern of clods grew significantly faster (mean horizontal growth rate: 10.4 mm(2)/year, 95% CI: 6.4-14.4 mm(2)/year) than melanomas with mainly a reticular pattern (4.8 mm(2)/year, 95% CI: 2.7-7.0 mm(2)/year) or with other patterns (2.6 mm(2)/year, 95% CI: -0.5-5.6 mm(2)/ year, p=0.01).

CONCLUSION

Morphologic characteristics of melanoma are associated with biologic behavior. Large and numerous epidermal nests (corresponding to a pattern of clods dermatoscopically) indicate more rapid growth.

[Clinical-pathological features of cutaneous melanomas diagnosed in a Mediterranean tertiary hospital between 1990 and 2004: a comparison between sexes and age groups and analysis of longterm outcomes]

BACKGROUND

The incidence of malignant melanoma has increased over recent decades. Early diagnosis continues to be essential for effective treatment. Our objective was to analyze cutaneous malignant melanomas diagnosed over a 15-year period in a tertiary hospital for trends towards earlier diagnosis and to identify subgroups with poorer prognosis.

MATERIAL AND METHODS

Retrospective analysis of primary cutaneous melanomas analyzed in the pathology department of Hospital La Paz, Madrid, Spain, between 1990 and 2004.

RESULTS

In total, 526 melanomas were diagnosed. The mean (SD) Breslow thickness was 2.63 (4.84) mm and the median thickness was 0.98 mm (range, 0-65 mm). The mean size (widest point) was 16.59 (12.11) mm. The most common histological type was surface-spreading melanoma and the most common site was the trunk. Melanomas detected in men were generally larger and thicker than in women (P=0.05). Individuals aged over 60 years consulted for significantly thicker and larger tumors than younger individuals. The incidence of malignant melanomas has increased steadily over the years whereas the mean Breslow thickness and size have decreased.

CONCLUSIONS

Diagnosis of melanoma in Spain is made increasingly earlier, although locally advanced tumors are still sometimes seen in men and in individuals aged over 60 years.

The value of screening in melanoma

The incidence of cutaneous melanoma has increased substantially in most white populations during the past several decades. Despite improvements in the early recognition of melanoma and the use of novel diagnostic techniques that enhance our diagnostic capabilities, disease-related mortality remains a significant public health issue. In the absence of effective treatment approaches for advanced disease, the best means for reducing deaths by melanoma are screening as well as professional and public education. The role of population-or community-based screening remains controversial, but evidence from self-selected screening campaigns, health care professional surveillance, and specialized pigmented lesions clinics underscores the value of screening and early detection programs, particularly in high-risk groups. Annual screening campaigns coupled with intense media promotion have become commonplace in many countries, and despite their low yield of melanoma detection, the dissemination of educational material and information to the public during these events is important in increasing public awareness. Future directions should include using screening campaigns to target middle-aged and older men and persons of lower socioeconomic status, who suffer most from the burden of the disease and its associated mortality. On a worldwide scale, comprehensive educational and screening campaigns should be implemented or intensified in underserved areas and geographic regions with lower survival rates, such as Eastern European countries. A better understanding of the biology of the disease, already occurring with notable strides, will help us to define better those individuals who will benefit most from screening and early detection efforts. Technologic advances and new diagnostic modalities will afford a more reliable and vigilant surveillance of high-risk individuals, whereas the wide use of the Internet will enhance the distribution of relevant information to the public with the ultimate goal of achieving a better control of melanoma.

Absence de valeur prédictive des signes de régression histologique sur l’envahissement du ganglion sentinelle

BACKGROUND

The predictive value of regression in melanoma is debated.

AIM OF THE STUDY

A retrospective single-centre study to evaluate the correlation between regression in primary skin tumor and the presence of micrometastases in sentinel lymph nodes.

PATIENTS AND METHODS

Histological signs of regression in 84 melanomas (>1 mm) with corresponding sentinel lymph nodes were studied by two independent pathologists.

RESULTS

Regression was seen in 40 skin melanoma tumors while micrometastasis was seen in 24. Of the tumors with micrometastasis, only 10 were regressive (RR: 0.47, p=0.49). Breslow value>2 mm and male sex were predictive for node micrometastasis (RR: 4.6, p=0.03 and RR: 7.6, p=0.006, respectively). On multivariate analysis, these two factors were independent.

COMMENTS

These data suggest that regression in primary cutaneous melanoma is not predictive for lymph node metastasis.