Sentinel node biopsy in cutaneous melanoma

Proposed quality performance indicators of sentinel lymph node biopsy for cutaneous melanoma

BACKGROUND

Melanoma is a leading cause of morbidity and mortality in Australia and New Zealand. New Zealand has the highest melanoma incidence in the world alongside Australia at 54 per 100 000 persons. The aim of this study is to conduct a retrospective quality audit of sentinel lymph nodal biopsy (SLNB) practices from 2007 to 2019 of a high-volume melanoma surgeon. Primary outcome was false negative rate (FNR). Secondary outcomes were sentinel node (SN) identification and removal rate, and complication rates.

METHODS

A database was maintained, containing n = 553 consecutive SLNB's for cutaneous melanoma from 31 August 2007 to 31 August 2019. Patient characteristics and details of the primary lesion, sentinel lymph node biopsy, recurrence and complications were recorded.

RESULTS

SN's were successfully identified in 444 (99.6%) out of 446 patients with an FNR of 9.1%. Positive SN's were identified in 70 (12.7%) SLNB's. Complications occurred in 76 out of 553 (13.7%) SLNB's. A review of internationally published literature reveals an SN identification rate of 94.4-99.5% with an FNR of 4.0-37.5%. SLNB is the best staging tool for melanoma and gives potential access to adjuvant systemic treatment if >1 mm deposits are found. It is a day-stay procedure with a low-complication rate.

CONCLUSION

SLNB is a safe and reliable procedure utilized for cutaneous melanoma. We propose our data should be used alongside international SN series to establish Quality Performance Indicators to improve melanoma management.

Complications and Sequelae After Sentinel Lymph Node Biopsy in Melanoma: A Retrospective Cohort Study

BACKGROUND AND OBJECTIVE

Sentinel lymph node (SLN) biopsy is a staging, not a therapeutic, procedure. The benefits of SLN biopsy have been more modest than expected and could be outweighed by the risks, which remain unclear. The aim of this study was to describe complications and sequelae observed in patients with melanoma who underwent routine SLN biopsy at our hospital.

PATIENTS AND METHODS

In this retrospective cohort study, we performed a chart review of all patients with melanoma who underwent SLN biopsy at our hospital in Vigo, Spain, between January 2011 and July 2017.

RESULTS

In the period analyzed, 124 SLN biopsies were performed. Over a mean follow-up of 52.7 months (range 10.8-88.7 months). A percentage of 37.9 of the patients experienced complications. The complication rate after excluding patients who underwent lymph node dissection was 30.9%. In the full chort group, there were 14 scar-related complications (11.3%), 13 surgical wound infections (10.5%), 12 lymphedemas (9.7%), 11 seromas (8.9%), 4 hematomas (3.2%), 4 wound dehiscences (3.2%), 2 cases of lymphorrhagia (1.6%), 2 cases of sensitivity alteration (1.6%), and one urinary tract infection (0.8%). The most common sequela was lymphedema. Sequelae were on record for 15.3% of patients in the full cohort (7.5% of the patients who did not undergo lymphadenectomy). Smoking was associated with a 33 to 73% increased risk of complications. The main limitation of this study is the risk of information bias due to incomplete follow-up.

CONCLUSIONS

SLN biopsy is a melanoma staging procedure that causes complications and sequelae. Recommendations for its use in clinical practice guidelines should be revised and the risks and benefits carefully evaluated in each case. Smokers in particular seem to have a high risk of complications. Patients with melanoma could benefit greatly from the development of less invasive staging tools.

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.

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.

Factors predictive of the status of sentinel lymph nodes in melanoma patients from a large multicenter database

BACKGROUND

Numerous predictive factors for cutaneous melanoma metastases to sentinel lymph nodes have been identified; however, few have been found to be reproducibly significant. This study investigated the significance of factors for predicting regional nodal disease in cutaneous melanoma using a large multicenter database.

METHODS

Seventeen institutions submitted retrospective and prospective data on 3463 patients undergoing sentinel lymph node (SLN) biopsy for primary melanoma. Multiple demographic and tumor factors were analyzed for correlation with a positive SLN. Univariate and multivariate statistical analyses were performed.

RESULTS

Of 3445 analyzable patients, 561 (16.3%) had a positive SLN biopsy. In multivariate analysis of 1526 patients with complete records for 10 variables, increasing Breslow thickness, lymphovascular invasion, ulceration, younger age, the absence of regression, and tumor location on the trunk were statistically significant predictors of a positive SLN.

CONCLUSIONS

These results confirm the predictive significance of the well-established variables of Breslow thickness, ulceration, age, and location, as well as consistently reported but less well-established variables such as lymphovascular invasion. In addition, the presence of regression was associated with a lower likelihood of a positive SLN. Consideration of multiple tumor parameters should influence the decision for SLN biopsy and the estimation of nodal metastatic disease risk.

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.

One-day or two-day procedure for sentinel node biopsy in melanoma?

PURPOSE

We compared the outcome of a 1-day and a 2-day sentinel node (SN) biopsy procedure, evaluated in terms of lymphoscintigraphic, surgical and pathological findings.

METHODS

We studied 476 patients with melanoma from two melanoma centres using static scintigraphy and blue dye. A proportional odds model was used for statistical analysis.

RESULTS

The number of SNs visualized at scintigraphy increased significantly with time from injection to scintigraphy and activity left in the patient at scintigraphy, and depended on the melanoma location. The number of SNs removed at surgery increased with the number of SNs visualized at scintigraphy and time from injection to surgery. The frequency of nodal metastasis increased with increasing thickness and Clark level of the melanoma, and was highest for two SNs visualized at scintigraphy.

CONCLUSION

This study showed that early vs. late imaging and surgery do make a difference on the outcome of the SN procedure and confirmed the importance of the scintigraphic visualization of all true SNs.

Use of contrast-enhanced ultrasound imaging to detect the first draining lymph node (FDLN) in a swine model: correlation of imaging findings with the distance from the injection site to the FDLN

OBJECTIVE

The purpose of this study was to investigate the use of contrast-enhanced ultrasound imaging (CEUS) to detect the first draining lymph node (FDLN) in a swine model and to determine whether the distance from the contrast agent injection site to the FDLN has any affect on the ability to detect contrast-enhanced FDLNs.

METHODS

Thirteen swine (25-32 kg) were anesthetized during examinations and euthanized afterward. In every swine, 1 mL of a sulfur hexafluoride microbubble ultrasound contrast agent was bilaterally injected subcutaneously below a mammilla. The examined distances varied from 6 to 36 cm. The contrast-enhanced lymphatic channels were visualized with low-mechanical index CEUS and mapped from the injection site to the FDLN. After CEUS was performed, blue dye was injected in the same locations as the contrast agent, and dye-guided surgery was used to localize the FDLNs. To ensure the lymph node detected with the blue dye technique was the same found with CEUS, it was scanned again to confirm contrast enhancement.

RESULTS

After 26 injections, 22 inguinal FDLNs were detected with CEUS and the blue dye technique. After 4 injections in 2 swine, contrast-filled lymphatic channels were identified with a course running toward the neck. In all cases but 1, the FDLNs received the contrast agent within 5 minutes.

CONCLUSIONS

In this swine model, it was possible to use CEUS to locate the FDLNs. In these preliminary experiments, the distances from the contrast agent injection site to the FDLN did not affect the ability to detect the contrast-enhanced FDLNs.

The impact of factors beyond Breslow depth on predicting sentinel lymph node positivity in melanoma

BACKGROUND

In addition to Breslow depth, the authors previously described how increasing mitotic rate and decreasing age predicted sentinel lymph node (SLN) metastases in patients with melanoma. The objectives of the current study were to verify those previous results and to create a prediction model for the better selection of which patients with melanoma should undergo SLN biopsy.

METHODS

The authors reviewed 1130 consecutive patients with melanoma in a prospective database who underwent successful SLN biopsy. After eliminating patients aged <16 years and patients who had melanomas that measured <1 mm, 910 remaining patients were reviewed for clinical and pathologic features and positive SLN status. Univariate association of patient and tumor characteristics with positive SLN status was explored by using standard logistic regression techniques, and the best multivariate model that predicted lymph node metastases was constructed by using a backward stepwise-elimination technique.

RESULTS

The characteristics that were associated significantly with lymph node metastasis were angiolymphatic invasion, the absence of regression, increasing mitotic rate, satellitosis, ulceration, increasing Breslow depth, decreasing age, and location (trunk or lower extremity compared with upper extremity or head/neck). Previously reported interactions between mitotic rate and age and between Breslow depth and age were confirmed. The best multivariate model included patient age (linear), angiolymphatic invasion, the number of mitoses (linear), the interaction between patient age and the number of mitoses, Breslow depth (linear), the interaction between patient age and Breslow depth, and primary tumor location.

CONCLUSIONS

Younger age, increasing mitotic rate (especially in younger patients), increasing Breslow depth (especially in older patients), angiolymphatic invasion, and trunk or lower extremity location of the primary tumor were associated with a greater likelihood of positive SLN status. The current results support the use of factors beyond Breslow depth to determine the risk of positive SLN status in patients with cutaneous melanoma.

Routine use of FDG-PET scans in melanoma patients with positive sentinel node biopsy

PURPOSE

Positron emission tomography (PET) scanning is an efficient and well-known diagnostic tool in various malignant disorders. However, the utility of PET as a clinical routine screening procedure for the detection of subclinical metastases in stage III melanoma patients has not yet been established.

METHODS

Thirty-three patients with cutaneous malignant melanoma and subclinical lymph node metastases diagnosed by sentinel node biopsy (SNB) were submitted to( 18)F-fluoro-2-deoxy-D: -glucose (FDG) whole-body PET scanning within 100 days after SNB and wide local excision. Before PET scanning, patients were screened conventionally and found to be without evidence of further dissemination. Positive PET scan findings were evaluated by computed tomography scanning, magnetic resonance imaging and ultrasonography. Biopsy was performed whenever possible. The median follow-up was 15 months (range 6-39 months).

RESULTS

Nine patients (27%) had a positive PET scan performed after SNB and WLE. On verification, four cases (12%) were found to be true positive for melanoma metastasis and were thus upgraded from stage III to stage IV. Furthermore, one patient (3%) had another primary malignancy (prostate carcinoma), and two (6%) were found to have non-malignant lesions. Two PET-positive patients (6%) refused further investigations. In one case (3%) the PET scan was false negative. Twenty-three (69%) PET scans were true negative.

CONCLUSION

In a number of stage III melanoma patients with positive SNB, postoperative whole-body FDG-PET scanning revealed further melanoma dissemination not found by conventional screening methods and thus identified these cases as stage IV. Relevant therapy can accordingly be instituted earlier on the basis of FDG-PET scanning.