Excision margins in high-risk malignant melanoma

Population-Based Assessment of Surgical Treatment Trends for Patients With Melanoma in the Era of Sentinel Lymph Node Biopsy

Purpose

The surgical staging of melanoma dramatically changed with the introduction of sentinel lymph node (SLN) biopsy. In this study, Surveillance, Epidemiology, and End Results (SEER) data were examined to determine how surgical treatment is being carried out and whether SLN biopsy is being performed in melanoma patients in conformance with National Comprehensive Cancer Network (NCCN) guidelines.

Patients and Methods

The SEER database (1998 to 2001) was searched for all patients with invasive melanoma. NCCN guidelines were used to define optimal stage-specific surgical treatment. Treatment trends in patients with stages I to III disease were summarized, and multivariate analyses were performed to identify factors associated with nonadherence with treatment guidelines.

Results

A total of 21,867 melanoma patients were identified; 18,499 of these patients met the inclusion criteria. The number of patients diagnosed with stage III melanoma increased by 55.7% over the study period, and this corresponded to a 53% increase in the number of SLN biopsies performed annually. The odds ratios for nonadherence were 2.32, 2.27, and 1.54 for stages IB, II, and III disease, respectively, compared with stage IA melanoma. Multivariate analyses revealed that age more than 65 years, marital status, minority populations, and primary tumor location were associated with nonadherence with guidelines. Treatment patterns among tumor registries also varied significantly.

Conclusion

Stage migration is evident in the SEER registries in consort with increasing use of SLN biopsy. Although treatment trends are improving, SLN biopsy continues to be underused, particularly in the elderly and minority populations, in patients with truncal and head/neck melanomas, and also in some geographic regions of the United States.

Cutaneous melanoma: methods of biopsy and definitive surgical excision

The proper method of biopsy and definitive surgical excision of cutaneous melanoma is vital for optimal patient outcome. Clearly, the present authors' understanding of the pathophysiology of cutaneous melanoma continues to change at a rapid pace. Indeed, as the present authors' research efforts begin to expose some of the mysteries of melanoma, so do they begin to better understand the intricacies of this dreaded cancer. This article will highlight methods of biopsy for melanoma and the management of the primary tumor. The present authors review current recommendations for excision margins for the primary tumor, usefulness of lymphoscintigraphy, timing of definitive surgical excision, and issues unique for head and neck melanoma.

Molecular MR imaging of melanoma angiogenesis with alphanubeta3-targeted paramagnetic nanoparticles

Neovascularization is a critical component in the progression of malignant melanoma. The objective of this study was to determine whether alpha(nu)beta(3)-targeted paramagnetic nanoparticles can detect and characterize sparse alpha(nu)beta integrin expression on neovasculature induced by nascent melanoma xenografts ( approximately 30 mm(3)) at 1.5T. Athymic nude mice bearing human melanoma tumors were intravenously injected with alpha(v)beta(3)-integrin-targeted paramagnetic nanoparticles, nontargeted paramagnetic nanoparticles, or alpha(v)beta(3)-targeted-nonparamagnetic nanoparticles 2 hr before they were injected with alpha(v)beta(3)-integrin-targeted paramagnetic nanoparticles (i.e., in vivo competitive blockade) and imaged with MRI. Contrast enhancement of neovascularity in animals that received alpha(nu)beta(3)-targeted paramagnetic nanoparticles increased 173% by 120 min. Signal contrast with nontargeted paramagnetic nanoparticles was approximately 50% less than that in the targeted group (P < 0.05). Molecular MRI results were corroborated by histology. In a competitive cell adhesion assay, incubation of alpha(nu)beta(3)-expressing cells with targeted nanoparticles significantly inhibited binding to a vitronectin-coated surface, confirming the bioactivity of the targeted nanoparticles. The present study lowers the limit previously reported for detecting sparse biomarkers with molecular MRI in vivo. This technique may be employed to noninvasively detect very small regions of angiogenesis associated with nascent melanoma tumors, and to phenotype and stage early melanoma in a clinical setting.

Melanoma

The surgical management of melanoma continues to evolve. A large body of information serves as a foundation for the oncologic principles, surgical excisions, and reconstructive methodologies that are currently in use. This article serves as a guide for the physician considering surgical management of the melanoma patient.

Sentinel node status in melanoma patients is not predictive for overall survival upon multivariate analysis

Sentinel lymph node biopsy (SLNB) has become a widely accepted standard procedure in the staging of patients with cutaneous melanoma and absence of clinical lymph node metastases, although there is no final proof that SLNB influences overall survival in these patients. This study investigated the accuracy of SLNB and the clinical outcome of patients after a mean follow-up of 22 months. Between 1998 and 2003, SLNB was performed in 309 consecutive patients. Patients with one or more positive sentinel lymph nodes (SLNs) were subjected to selective lymphadenectomy (SL). Survival analyses were performed using the Kaplan–Meier approach. A Cox proportional-hazard analysis was used for univariate and multivariate analysis to explore the effect of variables on survival. Sentinel lymph nodes were identified in 299 of 309 patients (success rate: 96.8%). Of these, 69 (23%) had a positive SLN. The false-negative rate was 9.2%. Recurrence of disease to the regional lymph node basin (3.0%) and to the locoregional skin (2.6%) was rare in SLN-negative patients in contrast to SLN-positive patients (7.2 and 17.4%, respectively). The 3-year overall survival was 93 and 83% for SLN-negative and SLN-positive patients, respectively. Upon multivariate analysis, SLN status (P<0.001), Breslow thickness (P<0.02) and ulceration (P<0.026) were all found to be independent prognostic factors with respect to disease-free survival, whereas Breslow thickness proved to be the only significant factor with respect to overall survival.

Treatment and Outcomes of Melanoma with a Breslow's Depth Greater than or Equal to One Millimeter in a Regional Teaching Hospital

Local control and regional lymph node evaluation are the primary treatment goals for cutaneous primary melanoma. Historically, primary lesions were excised with large 3- to 5-cm radial margins. Recent clinical trials have suggested that similar survival and recurrence rates can be achieved with smaller margins of excision. In addition to excision of the primary lesion, the presence or absence of nodal metastasis is the single most powerful predictor of survival in patients with melanoma. Based on the available trials, the standard of care for a melanoma 1 mm or greater in depth is a wide local excision with a 2-cm margin and a sentinel lymph node biopsy (SLNB). The application of this standard in regional teaching hospitals is unknown. We performed a retrospective review of a cancer registry at a teaching hospital in South Carolina. This analysis included all patients who underwent surgery for melanoma at our institution between July 1997 and March 2003. Our single inclusion criterion was that the primary melanoma had to be 1 mm or greater in depth. Only 42 per cent of the patients underwent excision with a radial margin >2 cm, and only 60 per cent of the patients underwent SLNB. As time progressed, the use of SLNB at our institution increased; but, even as late as 2003, some patients did not receive SLNB. Adherence to standards did not appear to have an effect on overall survival. In conclusion, the current standard for the treatment of invasive melanoma greater than or equal to 1 mm in thickness is a 2-cm margin of excision and a SLNB. In this regional teaching hospital, surgical treatment and staging of melanoma did not strictly adhere to the standard.

Sentinel lymphonodectomy does not increase the risk of loco-regional cutaneous metastases of malignant melanomas

With regard to malignant melanoma, the impact of lymph node surgery on the development of loco-regional cutaneous metastases (LCM) has not yet been adequately addressed. However, this aspect is of interest, since sentinel lymphonodectomy (SLNE) has been suspected of causing LCM by inducing entrapment of melanoma cells. We analysed 244 patients with SLNE and compared the data with 199 patients treated with delayed lymph node dissection (DLND) for clinically palpable metastases. Analysis of both groups commenced at the time of excision of the primary tumour, using the Kaplan-Meier method. LCM that appeared as a first recurrence, as well as the overall probability of developing LCM, were recorded. For sentinel-negative patients with a primary melanoma >1mm thick, the 5-year probability of developing LCM as a first recurrence was 6.9 +/- 0.02% (+/-standard error of the mean (SEM)). The probability was 17.6 +/- 0.03% in the DLND group. Comparing the two node-positive subgroups, the probability of developing LCM as a first recurrence was significantly higher in patients with positive SLNE (27.3 +/- 0.05%, P = 0.03). However, the 5-year overall probability of developing LCM did not differ significantly in the node-positive groups (33.3% in the DLND group vs. 33.7% in patients with positive sentinel lymph nodes (SLNs)). Since early excision of lymphatic metastases by SLNE avoids nodal recurrences, thereby prolonging the recurrence-free interval, the chance of LCM to manifest as a first recurrence should inevitably increase. However, the overall in-transit probability is not increased after SLNE.

Histopathologic excision margin affects local recurrence rate: analysis of 2681 patients with melanomas < or =2 mm thick

OBJECTIVE

Prospective trials have shown that 1-cm and 2-cm margins are safe for melanomas <1 mm thick and > or =1 mm thick, respectively. It is unknown whether narrower margins increase the risk of LR or mortality.

SUMMARY BACKGROUND DATA

To determine the relationship between histopathologic excision margin, local recurrence (LR) and survival for patients with melanomas < or =2 mm thick.

METHODS

Data were extracted from the Sydney Melanoma Unit database for all patients with cutaneous melanoma < or =2 mm thick, diagnosed up to 1996. Patients with positive excision margins or follow-up <12 months were excluded, leaving 2681 for analysis. Outcome measures were LR (recurrence <5 cm from the excision scar), in-transit recurrence, and disease-specific survival. Factors predicting LR and overall survival were tested with Cox proportional hazards analysis.

RESULTS

Median follow-up was 83.8 months. LR was identified in 55 patients (median time to recurrence, 37 months). At 120 months, the actuarial LR rate was 2.9%. Five-year survival after LR was 52.8%. In multivariate analysis, only margin of excision and tumor thickness were predictive of LR (both P = 0.003). When all patients with a margin <0.8 cm in fixed tissue (corresponding to a margin of <1 cm in vivo) were excluded from analysis, margin was no longer significant in predicting LR. Thickness, ulceration, and site were predictive of survival, but margin was not (P = 0.49).

CONCLUSIONS

Histopathologic margin affects the risk of LR. However, if the in vivo margin is > or =1 cm, it no longer predicts risk of LR. Patient survival is not affected by margin.

Cutaneous melanoma

Episodic exposure of fair-skinned individuals to intense sunlight is thought to be responsible for the steadily increasing melanoma incidence worldwide over recent decades. Rarely, melanoma susceptibility is increased more than tenfold by heritable mutations in the cell cycle regulatory genes CDKN2A and CDK4. Effective treatment requires early diagnosis followed by surgical excision with adequately wide margins. Sentinel lymph node biopsy provides accurate staging, but no published results are yet available from clinical trials designed to assess the therapeutic efficacy of early complete regional node dissection in those with metastatic disease in a sentinel node. Magnetic resonance spectroscopy is one technique under investigation for non-invasive, in-situ assessment of sentinel nodes. Localised metastatic disease is best treated surgically. No postoperative adjuvant therapy is of proven value for improving overall survival, although numerous clinical trials of vaccines and cytokines are in progress. Medical therapies have contributed little to the control of established metastatic disease, but molecular pathways recently identified as being central to melanoma growth and apoptosis are under intense investigation for their potential as therapeutic targets.

Prior immunisation of patients with malignant melanoma with vaccinia or BCG is associated with better survival. An European Organization for Research and Treatment of Cancer cohort study on 542 patients

There is increasing evidence that infections and vaccinations play an important role in the normal maturation of the immune system. It was therefore of interest to determine whether these immune events also affect the prognosis of melanoma patients. A cohort study of 542 melanoma patients in six European countries and Israel was conducted. Patients were followed up for a mean of 5 years and overall survival was recorded. Biometric evaluations included Kaplan-Meier estimates of survival over time and Hazard Ratios (HRs), taking into account all known prognostic factors. During the follow-up between 1993 and 2002, 182 of the 542 patients (34%) died. Survival curves, related to Breslow's thickness as the most important prognostic marker, were in accordance with those observed in previous studies where the cause of death was known to be due to disseminated melanoma. In a separate analysis of patients, vaccinated with vaccinia or Bacille Calmette-Guerin (BCG), HRs and the corresponding 95% Confidence Intervals (CIs) were 0.52 (0.34-0.79) and 0.69 (0.49-0.98), respectively. Joint analyses yielded HRs (and 95% CIs) of 0.55 (0.34-0.89) for patients vaccinated with vaccinia, 0.75 (0.30-1.86) with BCG, and 0.41 (0.25-0.69) with both vaccines. In contrast, infectious diseases occurring before the excision of the tumour had little, or, at the most, a minor influence on the outcome of the melanoma patients. These data reveal, for the first time, that vaccination with vaccinia in early life significantly prolongs the survival of patients with a malignant tumour after initial surgical management. BCG vaccination seems to have a similar, although weaker, effect. The underlying immune mechanisms involved remain to be determined.

Local recurrence of melanoma

Local recurrence (LR) of cutaneous malignant melanoma (CMM) is a controversial issue, especially in regard to recommendations for margins of excision of primary CMM. Factual evidence in support of the belief that wider margins of excision decrease the risk of local recurrence is meagre, but recommendations for adjusting margins of excision according to tumour thickness are still presented. The histological features of LR indicate that two mechanisms are involved: (1) persistent growth of incompletely excised primary melanoma, and (2) local metastasis. The second group comprises the most common form of LR and is associated with a poor prognosis, indicating that it is a manifestation of systemic disease. The morphological features and the prognostic implications of LR indicate that many are due to haematogenous rather than lymphatic metastasis alone and, therefore, are not preventable by wider excisions beyond complete excision of the primary tumour itself. The concept that most LRs are metastases is consistent with the failure of wide margins of excision to prevent LR. The higher risk of LR associated with greater tumour thickness is associated with the increased risk of metastasis from the thicker tumours, not with the extent of excision. The resolution of the controversy regarding the primary surgical treatment of CMM depends on the recognition by pathologists and clinicians alike that the two types of LR have diagnostic microscopic features and that they have entirely different implications for prognosis.

Diagnosis of melanoma in the elderly and surgical implications

The diagnosis of primary melanoma is mainly related to the precocity on which a patient is referred to the specialist, but in elderly patients this may present some peculiar characteristics, one is anatomical, a typical melanoma of the face, the lentigo maligna melanoma and the second is attitudinal, the fact that elderly patients often do not refer a changing cutaneous lesion to a doctor until becoming symptomatic. The therapeutic approach has to be discussed with an anaesthesiologist if the procedure has to be conducted under general anaesthesia or with a cardiologist if under local anaesthesia. Once there are no contraindications medically, a similar oncological approach should be proposed without any reduction in radicality due to the elderly age.

Selective lymphadenectomy in sentinel node-positive patients may increase the risk of local/in-transit recurrence in malignant melanoma

AIM

To determine whether sentinel lymph node biopsy (SLNB) for cutaneous malignant melanoma, particularly when followed by selective lymphadenectomy (SL) if involved nodes are found, alters the incidence of local/in-transit recurrence.

METHODS

A literature overview of SLNB with or without SL has been performed, concentrating on the reported site(s) of first recurrence, and with specific reference to the incidence of local/in-transit recurrence. This is compared to the incidence after wide local excision (WLE) alone.

RESULTS

The incidence of local/in-transit recurrence after WLE alone is 2.5-6.3% over a given range of tumour thickness, and is 9.0% after SLNB (with or without SL). In the latter group, the local/in-transit recurrence rate is 5.7% following SLNB alone in SN-negative patients, and is 20.9% after SLNB plus SL in SN-positive patients.

CONCLUSIONS

The incidence of local/in-transit recurrence following selective lymphadenectomy in sentinel node-positive patients may be greater than four times the incidence expected. This possible iatrogenic risk should be confirmed or refuted by randomised controlled trial. Until then the SLNB procedure should be regarded as experimental and not performed outside validation trials.

Conduta para o melanoma cutâneo

A incidência do melanoma cutâneo vem aumentando significativamente de 1:1500 em 1935 para cerca de 1:75 no ano 2000. Contudo, atribuído a um diagnóstico cada vez mais precoce, têm-se observado uma melhora da sobrevida em cinco anos com diminuição da taxa de mortalidade geral entre 70 a 80% desde a década de 30. É o câncer mais prevalente na faixa etária entre 25 e 35 anos nos EUA. O Brasil ocupa a 15º posição com relação à incidência do tumor no mundo. O estadiamento inicial é baseado na pesquisa de sinais e sintomas que podem indicar doença metastática. Especial atenção deve ser dada à palpação de linfonodos regionais. A espessura e a ulceração são os principais fatores de risco independentes, em pacientes com melanoma primário com linfonodos livres. Já naqueles com metástases linfonodais, a presença de ulceração, de metástase detectada macroscopicamente e o número de linfonodos acometidos, são os principais índices de impacto na sobrevida. Pacientes com metástases para o pulmão possuem melhor prognóstico no primeiro ano de sobrevida em comparação àqueles com metástases para outros órgãos. A dosagem de DHL é fator prognóstico poderoso, sendo incluída no último estadiamento publicado, em pacientes com estádio IV da doença. A pesquisa do linfonodo sentinela já é técnica incorporada à conduta de pacientes com melanoma com reconhecido impacto no estadiamento, prognóstico e programação terapêutica. Devido à falta de padronização para o tratamento do melanoma, muitos pacientes ainda evoluem com um prognóstico reservado devido a uma conduta inicial inadequada. Os tratamentos vêm mudando significativamente e a proposta deste trabalho visa apresentar uma revisão com ênfase nas condutas preconizadas para o melanoma.

Management of in-transit metastases from cutaneous malignant melanoma

Background

In-transit metastases from cutaneous malignant melanoma (cutaneous or subcutaneous deposits between the primary melanoma and regional lymph nodes) represent late-stage disease, and their treatment should be tailored accordingly. This article reviews the pathology, clinical significance and treatment options for in-transit disease from melanoma.

Methods

An initial Medline search was undertaken using the keywords ‘melanoma and in-transit’ and ‘melanoma and non-nodal regional recurrence’. Additional original articles were obtained from citations in articles identified by the initial search.

Results and conclusion

In-transit metastases carry a poor prognosis. The method of treatment should be tailored to the extent of cutaneous disease. The first line of treatment remains complete excision with negative histopathological margins. There is no need for wide excision. Carbon dioxide laser therapy is valuable for multiple small cutaneous deposits. Isolated limb perfusion has a role for numerous or bulky advanced in-transit metastases in the limbs that are beyond the scope of simpler techniques. Systemic chemotherapy has response rates of about 25 per cent and is reserved for patients for whom surgery is no longer feasible.