Review and evaluation of sentinel node procedures in 250 melanoma patients with a median follow-up of 6 years

The Use of Indocyanine Green and Near-Infrared Fluorescence Imaging Versus Blue Dye in Sentinel Lymph Node Biopsy in Cutaneous Melanoma: A Retrospective, Cohort Study

BACKGROUND

The use of indocyanine green (ICG) and near-infrared fluorescence imaging is a promising option for sentinel lymph node (SLN) mapping in cutaneous melanoma. The study objective was to compare the performance of ICG and blue dye at detecting SLNs with radioisotope nanocolloid (technetium-99).

METHODS

Between April 2018 and June 2022, 293 consecutive patients with cutaneous melanoma (Breslow thickness ≥ 0.8 mm) underwent wide local excision and SLN biopsy. Patients were divided into group A (ICG; n = 122) and group B (blue dye; n = 163). All patients underwent SPECT/CT imaging preoperatively. SLN detection parameters and complications were compared between the groups.

RESULTS

A total of 285 patients had complete data and were included in the analysis. The median age was 62.0 (range 10-91) years, and 139 (48.8%) were female patients. The mean Breslow thickness was 2.6 mm, 89 (31.2%) patients had ulceration, and 179 (62.8%) patients had mitosis ≥ 1 mm2. The mean number of SLNs detected per patient in group A was 1.58 and group B was 1.48. In groups A and B, the SLN detection rate was 96.7% versus 89.6% (p = 0.022) and the pathological SLN detection rate was 92.3% versus 97.1% (p = 0.481), respectively.

CONCLUSIONS

ICG had a higher SLN detection rate and equal pathological SLN detection rate to blue dye. ICG may not be inferior to blue dye and is a useful adjunct to radioisotope in SLN biopsy in cutaneous melanoma.

The impact of sentinel lymph node mapping with hybrid single photon emission computed tomography/computed tomography in patients with melanoma. Comparison to planar radioisotopic lymphoscintigraphy

We studied the diagnostic value of 16 slices of single photon emission computed tomography (SPECT)/computed tomography (CT) in the anatomical localization, image interpretation and extra-sentinel lymph nodes (SLNs) detection compared to dynamic and static planar radioisotopic lymphoscintigraphy (PLS) in patients with melanoma. Eighty-two patients with melanoma underwent dynamic PLS, static PLS and SPECT/CT. Data were obtained using a dual head SPECT/CT 16 slices γ-camera. We evaluated the number and localization of SLNs detected with each imaging method. SPECT/CT demonstrated 48 additional SLNs in comparison with PLS in 29 patients. In five truncal and seven head-neck lesions, dynamic and static PLS failed to detect the SLNs found on SPECT/CT (false negative). In one case of truncal and one case of lower limb melanoma, the foci of increased activity interpreted on PLS as possible SLNs were confirmed to be non-nodal sites of uptake on SPECT/CT (false positive). PLS underestimated the number of SLNs detected, whereas SPECT/CT revealed higher agreement compared to the respective number from histological reports. SPECT/CT showed a better prediction of the number of SLNs and higher diagnostic parameters in comparison to planar imaging. SPECT/CT is an important complementary diagnostic modality to PLS, that improves detection, preoperative evaluation, anatomical landmarks of SLNs and surgical management of patients with melanoma.

Prognostic Significance and Management of Sentinel Nodes in the Triangular Intermuscular Space of Patients with Melanoma

BACKGROUND

The clinical significance of sentinel nodes (SNs) in the triangular intermuscular space (TIS) of patients with melanoma is poorly understood. This study aimed to determine their incidence and positivity rate, and to report their management and patient outcomes.

METHODS

This was a single-institution retrospective cohort study of patients with unilateral or bilateral TIS SNs on lymphoscintigraphy treated between 1992 and 2017. Recurrence-free survival was analyzed.

RESULTS

Lymphoscintigraphy identified TIS SNs in 266 patients. They were bilateral in 17 patients. Of the 2296 patients with a melanoma on the upper back, 259 (11%) had TIS SNs. Procurement of SNs was not attempted in 122 (43%) of the 283 cases and failed in 11 cases (7%). An SN was successfully retrieved from the TIS in 145 patients (53%) and contained metastasis in 18 of 150 TIS SNs. This was the only positive SN in 12 patients (8%), upstaging all of them. Of the 18 patients with a positive SN in the TIS, 9 (50%) underwent completion axillary lymph node dissection, but no additional involved nodes were found in any of these patients. Recurrence in the TIS was observed in six patients (5%), none of whom had their TIS SN surgically pursued previously.

CONCLUSIONS

Lymphoscintigraphy showed TIS SNs in 11% of patients with melanomas on their upper back. In such cases, retrieval of TIS SNs is required for accurate staging and to minimize the risk of TIS recurrence.

Mesenteric location of lymph node metastasis for colorectal cancer

BACKGROUND

The number of lymph node metastasis (LNM) is a strong prognostic factor in the treatment of colorectal cancer (CRC). However, the impact of the mesentery location on LNM remains unclear. We assessed the impact LNM location on the recurrence of stage III CRC.

METHODS

Subjects with CRC and pathologically positive LNM were enrolled retrospectively. We defined three groups: LNM adjacent to the tumour (group A), metastases with horizontal or vertical spread (group B), and metastases with both horizontal and vertical spread (group C). Recurrence-free survival (RFS) was the primary outcome measure used for the study.

RESULTS

A total of 241 (Group A: 121, B: 90, and C: 30) patients were recruited for the study. Multivariate analysis by Cox regression model indicated LNM location to be an independent predisposing risk factor for recurrence [group B: Hazard ratio (HR) 2.01, 95% Confidential interval (CI) 1.12-3.60, P = 0.019; group C: HR 3.00, 95% CI 1.34-6.72, P = 0.008]. Addition of mesentery spread to the N classification was significant risk factor for recurrence (mN2a: HR 2.01, 95% CI 1.07-3.78, P = 0.029; mN2b: HR 3.96, 95% CI 2.12-7.40, P < 0.01). Comparison of Harrell's C-index values was conducted, and the modified N staging risk was 0.6377, whereas the TNM N stage classification was 0.5869.

CONCLUSION

Mesentery location of LNM was a risk factor and consideration of it might be beneficial for accurate prediction of CRC prognosis.

Indocyanine Green Fluorescence Imaging with Lymphoscintigraphy Improves the Accuracy of Sentinel Lymph Node Biopsy in Melanoma

BACKGROUND

Despite advances in melanoma management, there remains room for improvement in the accuracy of sentinel lymph node biopsy. The authors analyzed a prospective cohort of patients with primary cutaneous melanoma who underwent sentinel lymph node biopsy with lymphoscintigraphy and indocyanine green fluorescence to evaluate the quality and accuracy of this technique.

METHODS

Consecutive primary cutaneous melanoma patients who underwent sentinel lymph node biopsy with radioisotope lymphoscintigraphy and indocyanine green fluorescence from 2012 to 2018 were prospectively enrolled. Analysis was performed of melanoma characteristics, means of identifying sentinel lymph nodes, sentinel lymph node status, and recurrence.

RESULTS

Five hundred ninety-four melanomas and 1827 nodes were analyzed; 1556 nodes (85.2 percent) were identified by radioactivity/fluorescence, 255 (14 percent) by radioactivity only, and 16 (0.9 percent) with indocyanine green only. There were 163 positive sentinel nodes. One hundred forty-seven (90.2 percent) were identified by radioactivity/fluorescence, 13 (8 percent) by radioactivity only, and three (0.6 percent) with fluorescence only. Of the 128 patients with a positive biopsy, eight patients' (6.3 percent) nodes were identified by radioactivity only and four (3.4 percent) with fluorescence only. There were 128 patients with a positive biopsy, 454 with a negative biopsy, and 12 patients who had a negative biopsy with subsequent nodal recurrence. Mean follow-up was 2.8 years.

CONCLUSIONS

In the study of the largest cohort of patients with primary cutaneous melanoma who underwent a sentinel lymph node biopsy with radioisotope lymphoscintigraphy and indocyanine green-based technology, the quality and accuracy of this technique are demonstrated. This has important implications for melanoma patients, as the adoption of this approach with subsequent accurate staging, adjuvant workup, and treatment may improve survival outcomes. .

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, II.

Cranial nerve outcomes in regionally recurrent head & neck melanoma after sentinel lymph node biopsy

OBJECTIVE

Characterize long-term cranial nerve (CN) outcomes following sentinel lymph node biopsy (SLNB) based management for head and neck cutaneous melanoma (HNCM).

METHODS

Longitudinal review of HNCM patients undergoing SLNB from 1997-2007.

RESULTS

Three hundred fifty-six patients were identified, with mean age 53.5 ± 19.0 years, mean Breslow depth 2.52 ± 1.87 mm, and 4.9 years median follow-up. One hundred five (29.4%) patients had SLNB mapping to the parotid basin. Eighteen patients had positive parotid SLNs and underwent immediate parotidectomy / immediate completion lymph node dissection (iCLND), with six possessing positive parotid non-sentinel lymph nodes (NSLNs). Fifty-two of 356 (14.6%) patients developed delayed regional recurrences, including 20 total intraparotid recurrences: five following false negative (FN) parotid SLNB, three following prior immediate superficial parotidectomy, two following iCLND without parotidectomy, and the remaining 12 parotid recurrences had negative extraparotid SLNBs. Parotid recurrences were multiple (4.9 mean recurrent nodes) and advanced (n = 4 extracapsular extension), and all required salvage dissection including parotidectomy. Immediate parotidectomy/iCLND led to no permanent CN injuries. Delayed regional HNCM macrometastasis precipitated 16 total permanent CN injuries in 13 patients: 10 CN VII, five CN XI, and one CN XII deficits. Fifty percent (n = 10) of parotid recurrences caused ≥1 permanent CN deficits.

CONCLUSIONS

Regional HNCM macrometastases and salvage dissection confer marked CN injury risk, whereas early surgical intervention via SLNB ± iCLND ± immediate parotidectomy yielded no CN injuries. Further, superficial parotidectomy performed in parotid-mapping HNCM does not obviate delayed intraparotid recurrences, which increase risk of CN VII injury. Despite lack of a published disease-specific survival advantage in melanoma, early disease control in cervical and parotid basins is paramount to minimize CN complications.

LEVEL OF EVIDENCE

4 (retrospective case series) Laryngoscope, 130:1707-1714, 2020.

Sentinel Lymph Node Biopsy in Head and Neck Melanoma: Long-term Outcomes, Prognostic Value, Accuracy, and Safety

OBJECTIVE

To evaluate the long-term outcomes of sentinel lymph node biopsy (SLNB) for head and neck cutaneous melanoma (HNCM).

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary academic medical center.

SUBJECTS AND METHODS

Longitudinal review of a 356-patient cohort with HNCM undergoing SLNB from 1997 to 2007.

RESULTS

Descriptive characteristics included the following: age, 53.5 ± 19 years (mean ± SD); sex, 26.8% female; median follow-up, 4.9 years; and Breslow depth, 2.52 ± 1.87 mm. Overall, 75 (21.1%) patients had a positive SLNB. Among patients undergoing completion lymph node dissection following positive SLNB, 20 (27.4%) had at least 1 additional positive nonsentinel lymph node. Eighteen patients with local control and negative SLNB developed regional disease, indicating a false omission rate of 6.4%, including 10 recurrences in previously unsampled basins. Ten-year overall survival (OS) and melanoma-specific survival (MSS) were significantly greater in the negative sentinel lymph node (SLN) cohort (OS, 61% [95% CI, 0.549-0.677]; MSS, 81.9% [95% CI, 0.769-0.873]) than the positive SLN cohort (OS, 31% [95% CI, 0.162-0.677]; MSS, 60.3% [95% CI, 0.464-0.785]) and positive SLN/positive nonsentinel lymph node cohort (OS, 8.4% [95% CI, 0.015-0.474]; MSS, 9.6% [95% CI, 0.017-0.536]). OS was significantly associated with SLN positivity (hazard ratio [HR], 2.39; P < .01), immunosuppression (HR, 2.37; P < .01), angiolymphatic invasion (HR, 1.91; P < .01), and ulceration (HR, 1.86; P < .01). SLN positivity (HR, 3.13; P < .01), angiolymphatic invasion (HR, 3.19; P < .01), and number of mitoses (P = .0002) were significantly associated with MSS. Immunosuppression (HR, 3.01; P < .01) and SLN status (HR, 2.84; P < .01) were associated with recurrence-free survival, and immunosuppression was the only factor significantly associated with regional recurrence (HR, 6.59; P < .01).

CONCLUSIONS

Long-term follow up indicates that SLNB showcases durable accuracy, safety, and prognostic importance for cutaneous HNCM.

Indocyanine Green Fluorescence Imaging with Lymphoscintigraphy for Sentinel Node Biopsy in Melanoma: Increasing the Sentinel Lymph Node-Positive Rate

INTRODUCTION

The goal of this study was to analyze patients who underwent a sentinel lymph node biopsy (SLNB) in melanoma with the combination of radioisotope lymphoscintigraphy and indocyanine green (ICG) fluorescence imaging to compare our true positive (TP) rate, a means to perform immediate analysis of the SLNB, with that of the literature.

METHODS

Consecutive cutaneous melanoma patients who underwent SLNB with lymphoscintigraphy and ICG-based fluorescence imaging by the senior author (BG) from 2012 to 2018 were prospectively enrolled. The average expected SLN-positive rate per T stage was calculated based on three studies and compared with our SLN-positive rate.

RESULTS

Overall, 574 consecutive patients were analyzed. Average Breslow thickness was 1.9 mm. A total of 1754 sentinel nodes were sampled; 1497 were identified by gamma probe signaling and ICG, 241 were identified by gamma probe signaling only, and 16 were identified by ICG only. There were 123 (21.4%) patients with at least one positive SLN; 113 (91.9%) had at least one positive node identified with both gamma probe signaling and ICG, 8 (6.5%) had positive node(s) identified with gamma probe signaling only, and 2 (1.6%) had positive node(s) identified with ICG only. There was an overall 21.4% SLN-positive rate, with 8% T1, 18.5% T2, 41.1% T3, and 52.4% T4, which is higher than the predicted rates for each stage.

CONCLUSIONS

With the largest cohort of patients reported who underwent a melanoma SLNB with lymphoscintigraphy and ICG, we demonstrated that this technique results in higher SLN-positive rates than predicted. Patients are being followed but, given the TP data, knowledge of our results may foster the use of this modality to improve staging and treatment options.

Evaluation of Chest Radiographs and Laboratory Testing during Melanoma Staging Procedures

Chest radiographs (CXRs) and laboratory testing have historically been performed as a part of low-risk melanoma (clinical stage 1/2) workup. This study evaluates the utility of routine CXRs and laboratory testing during the staging of clinical stage 1 and 2 melanoma patients. This study was approved by the Institutional Review Board at Wake Forest University. A database of sentinel lymph node biopsies performed for clinical stage 1 or 2 melanoma was used to identify early-stage melanoma patients. The medical records of patients with melanoma were reviewed and pre-operative workup procedures were recorded. Four hundred sixty-three patients were reviewed. A total of 315 patients underwent a preoperative CXR, whereas 309 received some laboratory testing. After sentinel node biopsies, 168 patients had pathologic stage 1 disease, 103 stage 2, and 44 stage 3. None of the CXRs (0%) correctly identified metastatic melanoma. Suspicious locations on CXRs and laboratory testing did not lead to metastatic findings in any patient within a year. Metastatic melanoma was not found in any patient by screening with CXRs or laboratory testing during preoperative workup. We recommend not conducting CXRs or laboratory testing during workup for surgical melanoma patients because of charges and anxiety these tests can cause. CXRs, blood tests, and metabolic panels have historically been ordered for early melanoma patients, although debate remains on their efficacy. Surgical patient records were retrospectively reviewed for these tests and no benefit was found.

Melanoma & nuclear medicine: new insights & advances

The contribution of nuclear medicine to management of melanoma patients is increasing. In intermediate-thickness N0 melanomas, lymphoscintigraphy provides a roadmap for sentinel node biopsy. With the introduction of single-photon emission computed tomography images with integrated computed tomography (SPECT/CT), 3D anatomic environments for accurate surgical planning are now possible. Sentinel node identification in intricate anatomical areas (pelvic cavity, head/neck) has been improved using hybrid radioactive/fluorescent tracers, preoperative lymphoscintigraphy and SPECT/CT together with modern intraoperative portable imaging technologies for surgical navigation (free-hand SPECT, portable gamma cameras). Furthermore, PET/CT today provides 3D roadmaps to resect 18F-fluorodeoxyglucose-avid melanoma lesions. Simultaneously, in advanced-stage melanoma and recurrences, 18F-fluorodeoxyglucose-PET/CT is useful in clinical staging and treatment decision as well as in the evaluation of therapy response. In this article, we review new insights and recent nuclear medicine advances in the management of melanoma patients.

Metastatic Melanoma in Sentinel Node-Negative Patients: The Ottawa Experience

BACKGROUND

Lymph node involvement is a major independent prognostic factor for survival in patients with malignant melanoma. Sentinel lymph node biopsy (SLNB) detection of microscopic nodal melanoma has been shown to improve both 5-year survival and 5-year disease-free survival.

OBJECTIVE

To determine the rate of metastatic melanoma in SLNB-negative patients at long-term follow-up.

METHODS

Study subjects include all 152 patients who had a negative SLNB and were followed at the Ottawa Regional Cancer Centre (ORCC) between 1999 and 2004. Patients with a follow-up period less than 6 months, more than 1 primary melanoma, and metastatic melanoma at diagnosis were excluded. Age at diagnosis, sex, Breslow thickness, ulceration, mitoses, regression, Clark level, anatomical location, development of metastatic melanoma, time to detection of metastatic disease, and time to death from melanoma were studied.

RESULTS

In this retrospective study at the ORCC, 40 of 140 (28.6%) patients with a single primary melanoma developed metastatic melanoma following negative SLNB at a mean follow-up of 63 months.

CONCLUSION

The rate of metastatic melanoma following negative SLNB at long-term follow-up at the ORCC is higher than the upper limit of rates reported in the literature (6%-24%). The reason for this is multifactorial, and the long follow-up period of 5 years allowed for detection of metastatic disease at a mean of 3.9 years. Long-term prognosis may be guarded in node-negative patients with a primary cutaneous melanoma, and surveillance by a multidisciplinary team is crucial.

Surgical Management and Adjuvant Therapy for High-Risk and Metastatic Melanoma

Wide local excision is considered routine therapy after initial diagnosis of primary melanoma to reduce local recurrences, but it does not impact survival. Sentinel node staging is recommended for melanomas of intermediate thickness, but it has also not demonstrated any indisputable therapeutic effect on survival. The prognostic value of sentinel node staging has been long established and is therefore considered routine, especially in light of the eligibility criteria for adjuvant therapy (trials). Whether completion lymph node dissection after a positive sentinel node biopsy improves survival is the question of current trials. The MSLT-2 study is best powered to show a potential benefit, but it has not yet reported any data. Another study, the German DECOG study, presented at the 2015 American Society of Clinical Oncology (ASCO) Annual Meeting did not show any benefit but is criticized for the underpowered design and insufficient follow-up. There is no consensus on the use of adjuvant interferon in melanoma. This topic has been the focus of many studies with different regimens (low-, intermediate-, or high-dose and/or short- or long-term treatment). Adjuvant interferon has been shown to improve relapse-free survival but failed to improve overall survival. More recently, adjuvant ipilimumab has also demonstrated an improved relapse-free survival. Overall survival data have not yet been reported due to insufficient follow-up. Currently, studies are ongoing to analyze the use of adjuvant anti-PD-1 and molecular targeted therapies (vemurafenib, dabrafenib, and trametinib). In the absence of unambiguously positive approved agents, clinical trial participation remains a priority. This could change in the near future.

Melanoma: Clinical Presentations

The malignant cell in melanoma is the melanocyte. Because melanocytes are located in the basal layer of the epidermis, melanoma is most commonly seen on the skin. However, melanoma can also arise on mucosal surfaces such as the oral cavity, the upper gastrointestinal mucosa, the genital mucosa, as well as the uveal tract of the eye and leptomeninges. Melanomas tend to be pigmented but can also present as pink or red lesions. They can mimic benign or other malignant skin lesions. This chapter presents the spectrum of typical and less typical presentations of melanoma, as well as patterns of spread. It is divided into (1) cutaneous lesions; (2) patterns of regional spread, (3) non-cutaneous lesions; and (4) distant metastases.

Probabilistic issues with sentinel lymph nodes in malignant melanoma

OBJECTIVES

To address issues of probability for sentinel lymph node results in melanoma and provide details about the probabilistic nature of the numbers of sentinel nodes as well as to address how these issues relate to tumor thickness and patient outcomes.

METHODS

Analysis of the probability of observing sentinel node metastases uses the discrete exponential probability distribution to address the number of observed positive sentinel nodes. In addition, mathematical functions derived from survival analysis are used. Data are then chosen from the literature to illustrate the approach and to derive results.

RESULTS

Observations about the numbers of positive and negative sentinel nodes closely follow discrete exponential probability distributions, and the relationship between the probability of a positive sentinel node and tumor thickness follows closely a function derived from survival analysis. Sentinel node results relate to tumor thickness as well as to the total number of nodes harvested but fall short of identifying all those who eventually develop metastatic melanoma.

CONCLUSIONS

Probability analyses provide useful insight into the success and failure of the sentinel node biopsy procedure in patients with melanoma.

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.

[Sentinel lymph node biopsy in melanoma: our experience over 8 years in a universitary hospital]

BACKGROUND

Since the introduction of sentinel lymph node biopsy, its use as a standard of care for patients with clinically node-negative cutaneous melanoma remains controversial. Our experience of sentinel lymph node biopsy for melanoma is presented and evaluated.

MATERIAL AND METHODS

A cohort study was conducted on 69 patients with a primary cutaneous melanoma and with no clinical evidence of metastasis, who had sentinel lymph node biopsy from October-2005 to December-2013. Sentinel lymph node biopsy was identified using preoperative lymphoscintigraphy and subsequent intraoperative detection with gamma probe.

RESULTS

The sentinel lymph node biopsy identification rate was 98.5%. The sentinel lymph node biopsy was positive for metastases in 23 patients (33.8%). Postoperative complications after sentinel lymph node biopsy were observed in 4.4% compared to 38% of complications in patients who had complete lymphadenectomy.

CONCLUSION

The sentinel lymph node biopsy in melanoma offers useful information about the lymphatic dissemination of melanoma and allows an approximation to the regional staging, sparing the secondary effects of lymphadenectomy. More studies with larger number of patients and long term follow-up will be necessary to confirm the validity of sentinel lymph node biopsy in melanoma patients, and especially of lymphadenectomy in patients with positive sentinel lymph node biopsy.

Melanoma and nuclear medicine

Supported by a large body of published work, the contribution of nuclear medicine technologies to the assessment of melanoma has been increasing in recent years. Lymphoscintigraphy-assisted sentinel lymph node biopsy and PET are in continuous evolution with the aid of technological imaging advances, making it possible to fuse functional and anatomic images (e.g., with SPECT/CT, PET/CT and 3D rendering systems). The development of hybrid fluorescent-radioactive tracers that enable high-quality preoperative lymphoscintigraphy and SPECT/CT, and the optimization of modern intraoperative portable imaging technologies, such as free-hand SPECT and portable γ-cameras, are important innovations that have improved sentinel lymph node identification in complex anatomical areas, such as the pelvis and head and neck. Concurrently, ¹⁸F-fluorodeoxyglucose-PET has proved its usefulness in the clinical staging and treatment decision-making process, and there is also emerging evidence regarding its utility in the evaluation of therapeutic response. The potential uses of other novel PET radiotracers could open up a new field of use for this technique. In this article, we review the current and future role of nuclear medicine in the management of melanoma.

Sentinel lymph node biopsy for cutaneous melanoma: a 6 years study

Background:

The aim of this study was to evaluate the results of sentinel lymph node biopsy (SLNB) in cutaneous melanoma at our institution.

Materials and Methods:

128 patients with primary cutaneous melanoma who underwent SLNB between April, 2004, and August, 2010 were studied. Univariate and multivariate analysis was performed to explore the effect of variables on mortality and sentinel node status. Survival analysis was performed using the Kaplan-Meier approach.

Results:

Positive SLNB were detected in 35 (27.3%) of 128 cases. Mean Breslow depths were 3.7 mm for SLNB positive patients and 1.99 mm for SLNB negative patients. False negative rate was 1%. The recurrence rate was 40% for positive patients and 6.5% for negative patients (odds ratio 9.7 [confidence interval 95 % 3.3-28.1]). 33 patients (29%) had an ulcerated melanoma, 12 (10.5%) in the positive group and 21 (18.5%) in the negative group. The disease recurred in a 48.5% of patients with ulcerated melanoma, but only in a 2.5% of patients with non-ulcerated melanoma. Upon multivariate analysis, only Breslow thickness (P = 0.005) demonstrate statistically significance for SLNB status. Multivariate analysis for clinicopathologic predictors of death demonstrate statistically significance for Breslow thickness (P = 0.020), ulceration (P = 0.030) and sentinel node status (P = 0.020).

Conclusions:

This study confirms that the status of the sentinel node is a strong independent prognostic factor with a higher risk of death and lower survival. Patients with ulcerated melanoma are more likely to develop recurrence, and also higher risk of death than patients with non-ulcerated melanoma.

Sentinel lymph node biopsy for cutaneous melanoma: results of 10 years' experience in two regional training hospitals in the Netherlands

BACKGROUND AND OBJECTIVE

The Multicenter Selective Lymphadenectomy Trial (MSLT-I) demonstrated that the sentinel node (SN) status in cutaneous melanoma affects prognosis and that completion lymphadenectomy in SN-positive patients may improve survival. Our objective was to evaluate sentinel lymph node biopsy (SLNB) in two regional hospitals in the Netherlands.

METHODS

Patients with localized melanoma were planned for wide excision and SLNB. Completion lymphadenectomy was recommended for positive SN status. Data were compared with the MSLT-I.

RESULTS

A median of 2 (1-7) SNs were identified in 305 patients and complications occurred in 11%. Fifty-four patients (18%) demonstrated SN metastases and 45 underwent completion lymphadenectomy (20% additional metastases). Six patients with initially negative SN developed lymph node metastases (sensitivity 90%). Overall disease-free survival was 83% (SN-negative 91% vs. SN-positive 41%; p < 0.001) and melanoma-specific survival was 93% (SN-negative 97% vs. SN-positive 62%; p < 0.001). Multivariate regression analysis revealed the SN status to be the most significant predictor for recurrence and melanoma-related death.

CONCLUSION

Our results of SLNB are comparable to data from high-volume centers participating in MSLT-I. From a patient perspective, the false-negative SN rate of 10% and complication rate of 11% should be weighed against being informed about prognosis and having a possible therapeutic benefit from completion lymphadenectomy.

Decisive role of SPECT/CT in localization of unusual periscapular sentinel nodes in patients with posterior trunk melanoma: three illustrative cases and a review of the literature

Sentinel node mapping is widely applied in patients with melanoma. Although this type of skin cancer usually drains to the standard regional nodal basins, some patients have drainage to an unpredicted site. Nodes lying along a lymphatic channel, between the primary melanoma site and a common basin, are often called interval, in-transit, ectopic, intercalated, or aberrant nodes. They must be considered sentinel lymph nodes because they receive direct lymphatic drainage from a primary tumor site. Most investigators agree that interval sentinel nodes should be harvested; however, the management of melanoma patients with an involved interval sentinel node without established metastasis in the regional basin downstream is controversial. New and innovating technologies have improved nuclear medicine images, including single-photon emission computed tomography/computed tomography (SPECT/CT), a multimodal technique that fuses the radioactivity distribution detected by SPECT with the anatomic information harvested by CT. SPECT/CT does not replace the conventional planar images; it should be considered as a complementary modality for the search of sentinel lymph nodes. We report three illustrative cases that underline the decisive role of SPECT/CT with two-dimensional and three-dimensional reconstruction images to localize the uncommon periscapular sentinel nodes in patients with melanoma of the posterior trunk. The use of this image fusion technique on these patients leads to improved preoperative visualization of the sentinel nodes, may help identify additional periscapular interval sentinel nodes, and enables precise localization of the nodes with their surrounding anatomic structures. The cases are discussed together with a review of the literature.

When will selective lymphadenectomy become standard of care in melanoma?

In 2006 Meiron Thomas, writing in the British Journal of Surgery, made the following statement about the value of sentinel lymph node biopsy (SLNB) as a staging procedure in cutaneous malignant melanoma (1): "Perhaps a more important concern for those hoping to gain reassurance from accurate nodal staging relates to positive SN(S) that are prognostically inaccurate, information that can be devastating for the patient, leading to unnecessary lymphadenectomy and possibly unnecessary adjuvant therapy". In September 2011 Meyrick Ross and Gershenwald, writing in the Journal of Surgical Oncology, made the following statement about the management of patients with cutaneous malignant melanoma (2): "Sentinel node biopsy has become an important component of the initial management of many of these patients for accurate staging of regional lymph nodes, as well as enhanced regional disease control and improved survival in the patients with microscopically involved nodes." These two extremes have polarized the debate about the proper management of patients with malignant melanoma and have lead to widespread confusion and dismay amongst practicing clinicians, GP's and patient groups. In fact both statements are inaccurate, misleading and result from a false reading of the literature and in the case of Ross and Gershenwald a false interpretation of their own data (3). The following article explains why.

Preoperative ultrasound is not useful for identifying nodal metastasis in melanoma patients undergoing sentinel node biopsy: preoperative ultrasound in clinically node-negative melanoma

BACKGROUND

Sentinel lymph node biopsy (SLNB) is widely used in melanoma. Identifying nodal involvement preoperatively by high-resolution ultrasound may offer less invasive staging. This study assessed feasibility and staging results of clinically targeted ultrasound (before lymphoscintigraphy) compared to SLNB.

METHODS

From 2005 to 2009, a total of 325 patients with melanoma underwent ultrasound before SLNB. We reviewed demographics and histopathologic characteristics, then compared ultrasound and SLNB results. Sensitivity, specificity, and positive and negative predictive value were determined.

RESULTS

A total of 325 patients were included, 58% men and 42% women with a median age of 58 (range 18-86) years. A total of 471 basins were examined with ultrasound. Only six patients (1.8%) avoided SLNB by undergoing ultrasound-guided fine-needle aspiration of involved nodes, then therapeutic lymphadenectomy. Sixty-five patients (20.4%) had 69 SLNB positive nodal basins; 17 nodal basins from 15 patients with positive ultrasounds were considered truly positive. Forty-five SLNB positive basins had negative ultrasounds (falsely negative). Seven node-positive basins did not undergo ultrasound because of unpredicted drainage. A total of 253 patients with negative SLNBs had negative ultrasounds in 240 nodal basins (truly negative) but falsely positive ultrasounds occurred in 40 basins. Overall, sensitivity of ultrasound was 33.8%, specificity 85.7%, positive predictive value 36.5%, and negative predictive value 84.2%. Sensitivity and specificity improved somewhat with increasing Breslow depth. Sensitivity was highest for the neck, but specificity was highest for the groin.

CONCLUSIONS

Routine preoperative ultrasound in clinically node-negative melanoma is impractical because of its low sensitivity. Selected patients with thick or ulcerated lesions may benefit. Because of variable lymphatic drainage patterns, preoperative ultrasound without lymphoscintigraphic localization will provide incomplete evaluation in many cases.

The additional value of lymphatic mapping with routine SPECT/CT in unselected patients with clinically localized melanoma

PURPOSE

To investigate whether single photon emission computed tomography camera with integrated radiographic computed tomography (SPECT/CT) is of additional value compared to conventional lymphoscintigraphy in routine lymphatic mapping in patients with melanoma.

METHODS

Thirty-five unselected patients with a primary melanoma who were scheduled for wide local excision and sentinel node biopsy underwent conventional lymphoscintigraphy and subsequently SPECT/CT. We determined whether SPECT/CT showed additional sentinel nodes, whether it provided better information on the location of the sentinel nodes, and whether this additional anatomic information led to a change in the planned surgical approach.

RESULTS

SPECT/CT depicted the same 69 sentinel nodes as conventional lymphoscintigraphy in all 35 patients plus found eight additional sentinel nodes in seven patients (20%). In two of these patients (5.7%), an additional nodal basin had to be explored to find the extra sentinel nodes. SPECT/CT provided additional anatomic information that was helpful to the surgeon in 11 patients (31%) and led to an adjustment of the surgical approach in 10 patients (29%).

CONCLUSIONS

SPECT/CT provided relevant additional information in 16 (46%) of the 35 patients. Routine use of SPECT/CT in addition to conventional lymphoscintigraphy is recommended in melanoma patients undergoing lymphatic mapping.

Lymphatic mapping and sentinel lymph node biopsy in patients with melanoma: a meta-analysis

PURPOSE

To perform a meta-analysis of all published studies of sentinel lymph node (SLN) biopsy for staging patients with melanoma.

METHODS

Published literature in all languages between 1990 and 2009 was critically appraised. Primary outcomes evaluated included the proportion successfully mapped (PSM) and test performance including false-negative rate (FNR), post-test probability negative (PTPN), and positive predictive value in the same nodal basin recurrence.

RESULTS

A total of 71 studies including 25,240 patients met full eligibility criteria. The average PSM was 98.1% (95% CI, 97.3% to 98.6%) and increased with the year of publication, female sex, ulceration, age, and the quality score of the studies. The FNR ranged from 0.0% to 34.0%, averaging 12.5% overall (95% CI, 11% to 14.2%). FNR increased with the length of follow-up (P = .002) but decreased with greater PSM (P = .001). PTPN averaged 3.4% (95% CI, 3.0% to 3.8%), which also increased in studies with longer follow-up, younger age, female sex, deeper Breslow thickness, and with tumor ulceration while decreasing with greater PSM (P < .001). Approximately 20% of the patients with a positive SLN had additional lymph nodes in the complete lymph node dissection and 7.5% of the patients with positive SLN developed recurrence in the same nodal basin which was greater in studies that also reported higher FNR (P = .01).

CONCLUSION

The estimated risk of nodal recurrence after a negative SLN biopsy was ≤ 5% supporting the use of this technology for staging patients with melanoma.

Pelvic sentinel lymph node biopsy in melanoma patients: is it worthwhile?

The original procedure of intraoperative lymphatic mapping by using vital blue dye initially described by Morton and colleagues in 1992 was implemented in subsequent years by the introduction of preoperative lymphoscintigraphy (LS) and intraoperative gamma detection probe to allow a better identification of sentinel nodes (SNs). However, it is common, in practice, to detect more than one radioactive node with the gamma detection probe. Whether these additional lymph nodes represent true SNs is not yet clear. The aims of this study are: to investigate the role of pelvic sentinel node biopsy in recurrent pelvic disease in those patients with negative inguinal SN, having one or more deep hot spots identified by preoperative LS (follow-up group). One hundred and four stage I/II melanoma patients with primary tumor of the lower limb and lower trunk were enrolled in a restrospective study at the European Institute of Oncology, Milan, Italy, between 2000 and 2007. All patients presented hot spots both in superficial (groin) and deep (iliac-obturator) areas during dynamic LS. The study population consisted of 35 men and 69 women with a median age of 57 years at the time of diagnosis. The median follow-up period was 49 months (SD 22.4; range, 10-98 months). Of the 104 patients, 83 had a negative SN (80%). All sentinel-lymph-node-positive patients underwent superficial and deep inguinal dissection. Two patients (2.4%; 95% confidence interval: 1.5-8.8%) with negative SNs had pelvic recurrence. Among patients who underwent ilioinguinal dissection, three (14%; 95% confidence interval: 4-35%) had positive pelvic lymph nodes. After a 60-month follow-up, 79% of patients were alive and 66% were disease free. In SN-negative patients, disease-free survival was 69% and in SN-positive patients 53%. No significant difference was found by SN status (log-rank P values 0.15). Even if the sample size of our study cannot bring to conclusive results, and further studies are needed, it might be possible that harvesting pelvic SN in those patients with pelvic hot spots at LS could modify the natural history of melanoma patients in terms of pelvic recurrence and disease free survival. We recommend to improve our knowledge in the role of pelvic sentinel node in the natural history of melanoma.

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.

Cutting a sentinel lymph node into slices is the optimal first step for examination of sentinel lymph nodes in melanoma patients

The optimal processing for the pathology of sentinel lymph nodes of patients with melanoma is still a matter of debate. We compared two protocols of sentinel lymph node processing, which were consecutively applied. For the first protocol, the sentinel lymph nodes were cut into 1-2 mm thick slices. From each slice, 12 microtome sections were stained (multiple slices protocol). For the second protocol, which is a modification of the recent European Organisation for Research and Treatment of Cancer protocol, the sentinel lymph nodes were bivalved. Five consecutive series of microtome sections, with gaps of 50 microm between them, were prepared from each cut surface (bivalving protocol). H&E and immunohistochemical staining were integral elements of both protocols. A total of 584 sentinel lymph nodes (1.8+/-0.9 per patient) were examined. The percentages of micrometastases (29 versus 27%) and of capsular naevi (13 versus 15%) detected were very similar for both protocols. As shown by multivariate logistic regression, Breslow thickness (P=0.003) and younger age (P=0.01) correlated with nodal metastasis. The type of histological preparation, ulceration and sex were not significant. The multiple slices protocol produced, on average, 4 paraffin blocks and 46 microtome sections per node. The bivalving protocol constantly produced 2 paraffin blocks and 42 microtome sections. For technical processing, the multiple slices protocol required, on average, 38 min per sentinel lymph node, whereas the bivalving protocol required 55 min. Both protocols yielded excellent detection rates with a similar amount of work being required on the part of the pathologist. Compared with the bivalving protocol, the multiple slices protocol was less labor intensive for the technical staff.

Rotterdam Criteria for sentinel node (SN) tumor burden and the accuracy of ultrasound (US)-guided fine-needle aspiration cytology (FNAC): can US-guided FNAC replace SN staging in patients with melanoma?

PURPOSE

Sentinel node (SN) status is the most important prognostic factor for overall survival (OS) for patients with stage I/II melanoma, and the role of the SN procedure as a staging procedure has long been established. However, a less invasive procedure, such as ultrasound (US) -guided fine-needle aspiration cytology (FNAC), would be preferred. The aim of this study was to evaluate the accuracy of US-guided FNAC and compare the results with histology after SN surgery was performed in all patients.

PATIENTS AND METHODS

Four hundred consecutive patients who underwent lymphoscintigraphy subsequently underwent a US examination before the SN procedure. When the US examination showed a suspicious or malignant pattern, patients underwent an FNAC. Median Breslow thickness was 1.8 mm; mean follow-up was 42 months (range, 4 to 82 months). We considered the US-guided FNAC positive if either US and/or FNAC were positive. If US was suggestive of abnormality, but FNAC was negative, the US-guided FNAC was considered negative.

RESULTS

US-guided FNAC identified 51 (65%) of 79 SN metastases. Specificity was 99% (317 of 321), with a positive predictive value of 93% and negative predictive value of 92%. SN-positive identification rate by US-guided FNAC increased from 40% in stage pT1a/b disease to 79% in stage pT4a/b disease. US-guided FNAC detected SN tumors more than 1.0 mm in 86% of cases, SN tumors of 0.1 to 1.0 mm in 46% of cases, and SN tumors less than 0.1 mm in 23% of cases. Estimated 5-year OS rates were 92% for patients with negative US-guided FNAC results and 51% for patients with positive results.

CONCLUSION

US-guided FNAC of SNs is highly accurate. Up to 65% of the patients with SN-positive results in our institution could have been spared an SN procedure.

Is completion lymph node dissection needed in case of minimal melanoma metastasis in the sentinel node?

OBJECTIVE

The purpose of this study was to evaluate the micromorphometric Starz-classification in melanoma patients.

SUMMARY BACKGROUND DATA

The micromorphometric Starz-classification suggests that melanoma patients with a sentinel node metastasis invading no more than 0.3 mm (S-I) or 0.31 to 1.0 mm (S-II) below the capsular level can be spared further surgery, while invasion of the metastasis of more than 1.0 mm (S-III) implies a need for completion dissection.

METHODS

Seventy patients with sentinel node metastases were studied. Twenty patients with an S-I or S-II classification were spared further surgery and 50 S-III patients underwent completion dissection. The median follow-up time was 33 months.

RESULTS

No lymph node recurrences were detected in the 20 S-I, II patients. Six of the 50 S-III patients (12%) had additional involved nodes in the dissection specimen. In these patients no recurrences developed in the cleared regional basins. Overall 3-year survival was 100% in the S-I, II patients and 80% in the S-III patients (P = 0.04). Three-year disease-free survival rates were 83% and 60%, respectively (P = 0.40).

CONCLUSIONS

: This study suggests that further surgery is unnecessary in S-I and S-II patients, while it does seem prudent to carry out completion dissection in S-III patients. The distinct survival difference between the 2 groups of patients suggests that the S-classification also has prognostic implications.

Predicting outcome in melanoma: where are we now?

Melanoma incidence continues to rise in most countries. This is of grave concern, given the mortality rate in a relatively young population. Current staging tools are limited in their ability to predict accurately those at risk of metastatic disease, relapse and treatment failure. This overview comprehensively reviews relevant literature, with the focus on the last 5 years, and discusses the current state of traditional and emerging novel methods of staging for melanoma and their effect on prognosis in this population.

The yield of SPECT/CT for anatomical lymphatic mapping in patients with melanoma

BACKGROUND

The hybrid single-photon emission computed tomography camera with integrated CT (SPECT/CT) fuses tomographic lymphoscintigrams with anatomical CT data. SPECT/CT shows the exact anatomical location of a sentinel node and may detect additional drainage. The purpose of this study was to explore its potential in patients with melanoma.

METHODS

We studied 85 patients with melanoma with conventional lymphoscintigrams that were difficult to interpret (51 patients), that showed an unusual drainage pattern (33 patients), or with nonvisualization (1 patient). Forty-one patients had melanoma on an extremity, 31 on the trunk, and 14 in the head and neck region. SPECT/CT was performed following late conventional imaging without reinjection of the radiopharmaceutical.

RESULTS

Conventional imaging suggested 214 sentinel nodes in 84 of the 85 patients (99%). SPECT/CT showed these same nodes and 12 extra sentinel nodes in seven patients (8%). Ten of these additional nodes were harvested, of which three nodes of two patients harbored metastases. There was a clear advantage of SPECT/CT in 30 patients (35%), resulting in a different incision in 17 patients, an incision at another site in 8, and an extra incision in 5 patients. The value was questionable in 19 patients (22%) in whom sentinel nodes were more clearly visualized by SPECT/CT, although the incision remained unchanged. There was no additional value of SPECT/CT in 36 patients (42%).

CONCLUSIONS

SPECT/CT detects additional drainage and shows the exact anatomical location of sentinel nodes in patients with inconclusive conventional lymphoscintigrams. SPECT/CT facilitates surgical exploration in difficult cases and may improve staging.

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.