Lymphoscintigraphy and sentinel node biopsy accurately stage melanoma in patients presenting after wide local excision

What's new in pediatric melanoma: An update from the APSA cancer committee

BACKGROUND/PURPOSE

Melanoma is the most common skin cancer in children and often presents in an atypical fashion when compared to adults. The purpose of this review is to present an update on the epidemiology, surgical and medical management and prevention strategies in pediatric melanoma.

METHODS

A comprehensive review of the current literature on the epidemiology, surgical and medical management and prevention of adult and pediatric melanoma was performed by the authors and the results of this review are summarized in the manuscript.

RESULTS

Most recently, the incidence of melanoma in children has been declining, possibly owing to increased awareness and sun exposure prevention. The mainstay of therapy is surgical resection, often with sentinel lymph node biopsy. A positive sentinel node has prognostic value; however, completion node dissection is no longer recommended in the absence of clinically or radiographically positive nodes. Those with advanced disease also receive adjuvant systemic therapy using increasingly targeted immunologic therapies.

CONCLUSIONS

Sentinel lymph node positive patients no longer require completion lymph node dissection and instead may be followed by ultrasound. However, it is important to note that children have been excluded from most melanoma clinical trials to date, and therefore, recommendations for management are based on existing pediatric retrospective data and extrapolation from adult studies.

LEVEL OF EVIDENCE

IV.

Vertical Growth Phase as a Prognostic Factor for Sentinel Lymph Node Positivity in Thin Melanomas: A Systematic Review and Meta-Analysis

BACKGROUND

The 2010 American Joint Committee on Cancer guidelines recommended consideration of sentinel lymph node biopsy for thin melanoma (Breslow thickness <1.0 mm) with aggressive pathologic features such as ulceration and/or high mitotic rate. The therapeutic benefit of biopsy-based treatment remains controversial. The authors conducted a meta-analysis to estimate the risk and outcomes of sentinel lymph node positivity in thin melanoma, and examined established and potential novel predictors of positivity.

METHODS

Three databases were searched by two independent reviewers for sentinel lymph node positivity in patients with thin melanoma. Study heterogeneity, publication bias, and quality were assessed. Data collected included age, sex, Breslow thickness, mitotic rate, ulceration, regression, Clark level, tumor-infiltrating lymphocytes, and vertical growth phase. Positivity was estimated using a random effects model. Association of positivity and clinicopathologic features was investigated using meta-regression.

RESULTS

Ninety-three studies were identified representing 35,276 patients with thin melanoma who underwent sentinel lymph node biopsy. Of these patients, 952 had a positive sentinel lymph node biopsy, for an event rate of 5.1 percent (95 percent CI, 4.1 to 6.3 percent). Significant associations were identified between positivity and Breslow thickness greater than 0.75 mm but less than 1.0 mm, mitotic rate, ulceration, and Clark level greater than IV. Seven studies reported on vertical growth phase, which was strongly associated with positivity (OR, 4.3; 95 percent CI, 2.5 to 7.7).

CONCLUSIONS

To date, this is the largest meta-analysis to examine predictors of sentinel lymph node biopsy positivity in patients with thin melanoma. Vertical growth phase had a strong association with biopsy positivity, providing support for its inclusion in standardized pathologic reporting.

Single-stage excision and sentinel lymph node biopsy in cutaneous melanoma in selected patients: a retrospective case-control study

Sometimes, diagnostic excision of a primary melanoma would already necessitate skin grafting or transposition skin flaps, especially in areas with an esthetic or functional importance. The utility of sentinel lymph node biopsy (SLNB) after skin reconstruction is controversial. We carried out a single-institution retrospective case-control study. In patients with a wide primary lesion at high clinical-dermatoscopic suspicion for invasive melanoma in anatomical region in which a reconstruction with a skin graft or a flap is required, we proposed the performance of a confocal microscopy examination and an incisional biopsy of the primary lesion. If these diagnostic methodologies confirmed the suspicion of melanoma, lymphatic mapping was performed before the wide excision (WE) of the primary lesion, and WE and SLNB were performed during the same operative procedure. The database evaluation showed 496 patients who had undergone a previous complete local excision and a subsequent SLNB (two-stage group), whereas 61 patients underwent WE and SLNB during the same surgical time (one-stage group). Histological results of the excisional biopsy confirmed the diagnosis of melanoma in all patients of the one-stage group. The false-negative rate was lower in the one-stage group (5.5%) than in the two-stage group (16.7%). Patients of the two groups showed a similar recurrence-free and overall survival period even when corrected for clinic-demographical variables. The concomitant execution of SLNB and WE after confocal microscopy examination and incisional biopsy appears to be a safe and accurate procedure in patients with a wide primary melanoma that requires a skin flaps or a skin graft to cover the residual defect.

Sentinel Lymph Node Biopsy in Thin Cutaneous Melanoma: A Systematic Review and Meta-Analysis

BACKGROUND

Most patients with melanoma have a thin (≤1.00 mm) lesion. There is uncertainty as to which patients with thin melanoma should undergo sentinel lymph node (SN) biopsy. We sought to quantify the proportion of SN metastases in patients with thin melanoma and to determine the pooled effect of high-risk features of the primary lesion on SN positivity.

METHODS

Published literature between 1980 and 2015 was searched and critically appraised. Primary outcome was the proportion of SN metastases in patients with thin cutaneous melanoma. Secondary outcomes included the effect of high-risk pathological features of the primary lesion on the proportion of SN metastases. Summary measures were estimated by Mantel-Haenszel method using random effects meta-analyses.

RESULTS

Sixty studies (10,928 patients) met the criteria for inclusion. Pooled SN positivity was 4.5 % [95 % confidence interval (CI) 3.8-5.2 %]. Predictors of a positive SN were: thickness ≥0.75 mm [adjusted odds ratio (AOR) 1.90 (95 % CI 1.08-3.34); with a likelihood of SN metastases of 8.8 % (95 % CI 6.4-11.2 %)]; Clark level IV/V [AOR 2.24 (95 % CI 1.23-4.08); with a likelihood of 7.3 % (95 % CI 6.2-8.4 %)]; ≥1 mitoses/mm² [AOR 6.64 (95 % CI 2.77-15.88); pooled likelihood 8.8 % (95 % CI 6.2-11.4 %)]; and the presence of microsatellites [unadjusted OR 6.94 (95 % CI 2.13-22.60); likelihood 26.6 % (95 % CI 4.3-48.9 %)].

CONCLUSIONS

The pooled proportion of SN metastases in thin melanoma is 4.5 %. Thickness ≥0.75 mm, Clark level IV/V, mitoses, and microsatellites significantly increased the odds of SN positivity and should prompt strong consideration of SN biopsy.

EANM practice guidelines for lymphoscintigraphy and sentinel lymph node biopsy in melanoma

PURPOSE

Sentinel lymph node biopsy is an essential staging tool in patients with clinically localized melanoma. The harvesting of a sentinel lymph node entails a sequence of procedures with participation of specialists in nuclear medicine, radiology, surgery and pathology. The aim of this document is to provide guidelines for nuclear medicine physicians performing lymphoscintigraphy for sentinel lymph node detection in patients with melanoma.

METHODS

These practice guidelines were written and have been approved by the European Association of Nuclear Medicine (EANM) to promote high-quality lymphoscintigraphy. The final result has been discussed by distinguished experts from the EANM Oncology Committee, national nuclear medicine societies, the European Society of Surgical Oncology (ESSO) and the European Association for Research and Treatment of Cancer (EORTC) melanoma group. The document has been endorsed by the Society of Nuclear Medicine and Molecular Imaging (SNMMI).

CONCLUSION

The present practice guidelines will help nuclear medicine practitioners play their essential role in providing high-quality lymphatic mapping for the care of melanoma patients.

Nodal staging in penile carcinoma by dynamic sentinel node biopsy after previous therapeutic primary tumour resection

BACKGROUND

Dynamic sentinel node biopsy (DSNB) is used to evaluate the nodal status of patients with penile carcinoma and clinically node-negative groins. This minimally invasive procedure is usually done at the same time as the treatment of the primary tumour.

OBJECTIVE

Our aim was to evaluate results of so-called postresection DSNB, that is, DSNB after previous resection of the penile tumour.

DESIGN, SETTING, AND PARTICIPANTS

All 40 patients who had undergone DSNB after previous penile carcinoma resection with histopathologically tumour-negative margins between February 2003 and July 2009 were analysed. Twenty patients (50%) had known unilateral nodal involvement, and DSNB was used to stage the clinically normal contralateral groin. Hence the study concerned 60 groins without palpable nodes. The median time between primary tumour resection and DSNB was 2.8 mo. The technique of postresection DSNB was similar to the standard procedure.

MEASUREMENTS

The sentinel node visualisation rate, identification rate, histopathologic results, and outcome during follow-up were investigated.

RESULTS AND LIMITATIONS

A sentinel node was visualised on the lymphoscintigrams of 56 of the 60 eligible groins (93%). A sentinel node was identified intraoperatively in all these 56 groins. A median of two sentinel nodes were removed. Histopathologic analysis revealed involvement of seven groins (12%) in seven patients (18%). The median size of these metastases was 6mm. Additional dissemination was found in one completed ipsilateral inguinal node dissection specimen. No recurrences developed in the groins from which one or more tumour-free sentinel nodes had been taken during a median follow-up of 28 mo after the primary tumour resection. A potential limitation of this study is the short follow-up and relatively small cohort number.

CONCLUSIONS

Postresection DSNB is a suitable procedure to stage clinically node-negative penile carcinoma after previous therapeutic primary tumour resection. The results seem similar to the favourable experience with DSNB in patients with their tumour still present.

EANM-EORTC general recommendations for sentinel node diagnostics in melanoma

The accurate diagnosis of a sentinel node in melanoma includes a sequence of procedures from different medical specialities (nuclear medicine, surgery, oncology, and pathology). The items covered are presented in 11 sections and a reference list: (1) definition of a sentinel node, (2) clinical indications, (3) radiopharmaceuticals and activity injected, (4) dosimetry, (5) injection technique, (6) image acquisition and interpretation, (7) report and display, (8) use of dye, (9) gamma probe detection, (10) surgical techniques in sentinel node biopsy, and (11) pathological evaluation of melanoma-draining sentinel lymph nodes. If specific recommendations given cannot be based on evidence from original, scientific studies, referral is given to "general consensus" and similar expressions. The recommendations are designed to assist in the practice of referral to, performance, interpretation and reporting of all steps of the sentinel node procedure in the hope of setting state-of-the-art standards for good-quality evaluation of possible spread to the lymphatic system in intermediate-to-high risk melanoma without clinical signs of dissemination.

Imaging in cutaneous melanoma

Cutaneous melanoma (CM) is a common malignancy and imaging, particularly lymphoscintigraphy (LS), positron-emission tomography with 2-fluoro-2-deoxyglucose (FDG-PET), ultrasound, radiography computed tomography (CT) and magnetic resonance imaging have important roles in staging and restaging, surgical guidance, surveillance and assessment of recurrent disease. This review aims to summarize the available data regarding these and other imaging modalities in CM and provide the basis for subsequent formulation of guidelines regarding the use of imaging in CM. PubMed and Medline searches were performed and reference lists from publications were also searched. The published data were reviewed and tabulated. There is level I evidence supporting the use of LS and sentinel lymph node biopsy in nodal staging for CM. There is level III evidence demonstrating the superiority of ultrasound to palpation in the assessment of lymph nodes in CM. There is level IV evidence supporting FDG-PET in American Joint Committee on Cancer stage III/IV and recurrent CM and that FDG-PET/CT may be superior to FDG-PET. Level IV evidence also supports the use of CT in the same group of patients and the role of CT appears to be complementary to FDG-PET. Various imaging modalities, especially LS/sentinel lymph node biopsy and FDG-PET/CT, add incremental information in the management of CM and the various modalities have complementary roles depending on the clinical situation.

Accuracy of lymphatic mapping and sentinel lymph node biopsy after previous wide local excision in patients with primary melanoma

BACKGROUND

Sentinel lymph node (SLN) status is the most important prognostic factor with respect to the survival of patients with primary cutaneous melanoma. However, lymphatic mapping and SLN biopsies (LM/SLNBs) performed in patients who have had a wide local excision (WLE) may not accurately reflect the pathologic status of the draining lymph node basins. The purpose of this study was to assess the feasibility and accuracy of LM/SLNB in patients who have had a previous WLE.

METHODS

A single-institution database was examined to identify patients who had a WLE before LM/SLNB and patients who had a concomitant LM/SLNB. Primary clinicopathologic features (age, tumor thickness, and ulceration), SLN identification rate, SLN pathologic status, and the incidence and sites of recurrences were compared between patients with and without prior WLE.

RESULTS

Of the 1395 patients identified, 104 had WLE before LM/SLNB. The mean preoperative WLE radial margin was 1.4 cm (median, 1.0 cm). LM/SLNB was successful in 103 of 104 (99%) patients. Age, tumor thickness, incidence of ulceration, and incidence of SLN positivity in the group with prior WLE were similar to those of the cohort of patients who had concomitant LM/SLNB and WLE (n = 1291). In 97 (93%) of the 104 prior-WLE patients, the surgical defects were closed by either primary closure or skin graft; 7 patients (7%) had rotational flaps. The median follow-up of these 104 patients was 51 months. Among the prior-WLE group, 19 patients (18%) had a positive SLNB; of these 19 patients, 4 (21%) had recurrences (3 distant failures and 1 local and distant failure). There were no lymph node recurrences-in a mapped or unmapped basin-in these 104 patients with a negative or positive SLNB.

CONCLUSIONS

SLNs can be successfully identified and accurately reflect the status of the regional lymph node basin in carefully selected melanoma patients with a previous WLE. Prior WLE does not appear to adversely impact the ability to detect lymphatic metastases, although the utility of LM/SLNB in patients who have undergone extensive reconstruction of the primary excision site remains to be defined. Because more extensive surgery may be required to accomplish accurate lymph node staging in patients who have undergone prior WLE-including the possible removal of SLNs from additional lymph node basins and an additional surgical procedure-to minimize morbidity and cost, concomitant WLE and LM/SLNB is strongly preferred whenever possible.

Method of biopsy and incidence of positive margins in primary melanoma

BACKGROUND

The staging of patients with primary melanoma is dependent on adequate sampling of the tumor thickness. Initial biopsies with a positive deep margin suggest inadequate sampling, potentially limiting accurate staging and affecting treatment decisions.

METHODS

To determine the efficacy of shave biopsy to adequately sample the tumor, we retrospectively reviewed our pathology database for original pathology reports of primary melanomas accessioned between 01/01/04 and 6/30/05. The biopsies were evaluated by technique, the presence of tumor at the margins of the specimen, and specimen thickness.

RESULTS

We identified 240 cases of primary melanoma; 223/240 were analyzable. The specimens were divided by biopsy technique (excisional, n = 51; punch, n = 44; and shave, n = 128). Shave and punch specimens had a significantly higher percentage of positive margins than excisional specimens (50, 68, and 16%, respectively; P < 0.0001). Shave specimens had a significantly higher percentage of positive deep margins than punch or excisional specimens (22, 7, and 2%, respectively; P = 0.0009). For melanomas <or=1 mm, shave specimens had a significantly higher percentage of positive deep margins than punch or excisional specimens (17, 0, and 0%, respectively; P = 0.0014). There was a significant difference in specimen thickness (P = 0.0005), with shave specimens being the thinnest.

CONCLUSIONS

The presence of tumor at the lateral margin of punch biopsies is an expected result, since this method is often used to diagnose lesions with a large diameter. The presence of positive deep margins in 22% of shave biopsy specimens compromises the ability of this technique to properly stage patients.

Melanoma arising in a skin graft

Cutaneous melanoma remains an ongoing public health threat, and the cornerstone of management continues to be early diagnosis and treatment. Unfortunately, primary melanomas may have atypical presentations, making early diagnosis difficult and causing significant treatment delays. In this report, an unusual case is presented in which a patient experienced the synchronous development of a melanoma in situ within a skin graft donor site and an invasive melanoma within the recipient skin graft site. This exceptional presentation of cutaneous melanoma is discussed to highlight key principles of skin grafting in relation to the management of malignant melanoma.

Indications for lymphatic mapping and sentinel lymphadenectomy in patients with thin melanoma (Breslow thickness < or =1.0 mm)

BACKGROUND

Patients with thin (Breslow thickness < or =1.0 mm) melanoma have a good prognosis (5-year survival >90%). Consequently, the added benefit of lymphatic mapping and sentinel lymphadenectomy (LM/SL) in these patients is controversial. We hypothesize that LM/SL with a focused examination of the sentinel node (SN) will detect a significant number of SN metastases in patients with thin melanoma and that certain clinical or histopathologic factors may serve as predictors of SN tumor involvement.

METHODS

Over 6 years, 349 patients with melanoma underwent LM/SL and were prospectively entered into an institutional review board (IRB)-approved database. LM/SL was performed with a combined radiotracer and blue dye technique. SNs were serially sectioned, and each section was examined by a dermatopathologist at multiple levels with hematoxylin and eosin as well as immunohistochemical stains.

RESULTS

One hundred forty-six patients (42%) had a melanoma with Breslow thickness < or =1.0 mm; six (4%) of these 146 patients had a tumor-involved SN. On multivariate analysis, none of the clinical or histopathologic factors examined were significantly associated with SN tumor involvement in patients with thin melanoma. Completion lymphadenectomy was performed on all patients with a tumor-involved SN. None of the patients had non-SN tumor involvement.

CONCLUSIONS

The incidence of SN tumor involvement in patients with thin melanoma is considerable. Although we were unable to identify predictors of SN tumor involvement in patients with thin melanoma, efforts to identify predictors of SN tumor involvement should continue. Until better predictors are identified, we continue to advocate offering LM/SL to patients with thin melanomas who demonstrate clinical or histopathologic characteristics that have historically been associated with an increased risk of recurrence and mortality.

[Sentinel lymph node in melanoma]

The procedure of sentinel node biopsy (SNB) has emerged as an important advance especially with respect to staging of malignant melanoma. Elective (prophylactic) lymph node dissection that had been practiced in primary melanoma with a suspected increased risk of (clinically occult) lymphatic metastasis has been replaced by SNB. Patients with proven metastatic involvement of the sentinel node (12-25%) can be specifically selected for regional lymph node dissection. Metastatic involvement of the sentinel node (SN) is a significant independent prognostic factor. The value of detecting metastasis by highly sensitive diagnostic tools such as RT-PCR is just as uncertain as is the therapeutic benefit of operative or conservative therapies in sentinel node-positive patients with respect to improving prognosis and is currently under study.

Selective sentinel lymphadenectomy for malignant melanoma

To date, selective sentinel lymphadenectomy (SSL) should be considered a standard approach for staging patients with primary invasive melanoma greater than or equal to 1 mm. It is imperative that the multidisciplinary team master the techniques of preoperative lymphoscintigraphy, intraoperative lymphatic mapping, and postoperative pathologic evaluation of the sentinel lymph nodes (SLNs). A SLN is defined as a blue, "hot", or any subsequent lymph node greater than 10% of the in vivo count of the hottest lymph node and as an enlarged or indurated lymph node. Frozen sections are not recommended. For extremity melanoma, delayed SSL may be performed. Preoperative lymphoscintigraphy for extremity melanoma may be done the night before so that surgery can be scheduled as the first case of the following day. Every surgeon who uses blue dye should be cognizant of the potential adverse reaction to isosulfan blue and treatment for such a potential fatal reaction. A complete lymph node dissection is done if the SLN is found to be positive. Elective lymph node dissection should not be done if SSL can be done as a staging procedure. It is important for investigators involved with SSL to follow the clinical outcome of their patients so that the role of SSL can be further defined.