Optimal selective sentinel lymph node dissection in primary malignant melanoma

Ultrasound Surveillance in Melanoma Management: Bridging Diagnostic Promise with Real-World Adherence: A Systematic Review and Meta-Analysis

BACKGROUND

Ultrasound surveillance has become the new standard of care in stage III melanoma after the 2017 Multicenter Selective Lymphadenectomy Trial II (MSLT-II) demonstrated non-inferior 3-year survival compared with complete lymph node dissection.

OBJECTIVE

We aimed to quantify diagnostic performance and adherence rates of ultrasound surveillance for melanoma locoregional metastasis, offering insights into real-world applicability.

METHODS

Conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we systematically searched the Medline, Embase, Cochrane Library, CINAHL, Scopus, and Web of Science databases from inception until 11 October 2023. All primary studies that reported data on the diagnostic performance or adherence rates to ultrasound surveillance in melanoma were included. R statistical software was used for data synthesis and analysis. Sensitivity and specificity were aggregated across studies using the meta-analytic method for diagnostic tests outlined by Rutter and Gatsonis. Adherence rates were calculated as the ratio of patients fully compliant to planned follow-up to those who were not.

RESULTS

A total of 36 studies including 18,273 patients were analysed, with a mean age of 56.6 years and a male-to-female ratio of 1:1.11. The median follow-up duration and frequency was 36 and 4 months, respectively. The pooled sensitivity of ultrasound examination was 0.879 (95% confidence interval [CI] 0.878-0.879) and specificity was 0.969 (95% CI 0.968-0.970), representing a diagnostic odds ratio of 224.5 (95% CI 223.1-225.9). Ultrasound examination demonstrated a substantial improvement in absolute sensitivity over clinical examination alone, with a number needed to screen (NNS) of 2.95. The overall adherence rate was 77.0% (95% CI 76.0-78.1%), with significantly lower rates in the United States [US] (p <  0.001) and retrospective studies (p <  0.001).

CONCLUSION

Ultrasound is a powerful diagnostic tool for locoregional melanoma metastasis. However, the real applicability to surveillance programmes is limited by low adherence rates, especially in the US. Further studies should seek to address this adherence gap.

Primary Melanoma: from History to Actual Debates

PURPOSE OF REVIEW

This review describes the long scientific background followed to design guidelines and everyday clinical practice applied to melanoma patients. Surgery is the first option to cure melanoma patients (PTS) at initial diagnosis, since primary cutaneous lesions are usually easily resectable. An excisional biopsy of the lesion, with minimal clear margins, can be obtained in the vast majority of cases. Punch biopsies may be proposed only in case of large lesions located on specific cosmetic or functional areas like the face, extremities, or genitals where a mutilating complete resection would not be performed without prior histological diagnosis.

RECENT FINDINGS

After the histologic confirmation of melanoma, definite surgical excision of the scar and surrounding tissue is planned, to obtain microsatellite free margins. The width of these margins has been identified following the results of several clinical trials and it is either 1 or 2 cm, depending on the Breslow thickness of the primary tumor. Following the latest staging system proposed by the American Joint Cancer commission (AJCC), a sentinel node biopsy (SNB) is usually performed in case of a primary lesion > 0.8 mm thickness or for high-risk thinner lesions, if no evidence of nodal involvement has been identified clinically or radiographically. Surgical management of primary melanoma is well established. There is debate on the optimal surgical margins for 1-2 mm melanomas. There are specific considerations for special primaries (bulky, extremity, mucosal). Sentinel node (SN) evaluation does not improve survival, but is routinely used as staging.

State of the Art of Sentinel Node Biopsy in Oncology

Sentinel node biopsy has become a standard diagnostic procedure to assess lymph node status of various tumors. The combination of blue dye and a radioactive tracer offers the best chances of identifying the sentinel lymph node. Most progress in the technique of the sentinel node procedure has been made in melanoma and breast cancer. In melanoma, sentinel node biopsy has been introduced as a fundamental procedure for staging. Information on the lymphatic drainage from a melanoma can have a direct impact on the surgery. More recently, the technique has been successfully introduced in the management of breast cancer, in which a large number of unnecessary axillary dissections could be avoided. However, there are many other potential fields of application of the sentinel node biopsy (e.g. endometrial, vulvar, head and neck cancers) that are worthy of investigation. In any case, multicenter trials are required to standardize the procedures, taking into account several variables such as particle size and mode of delivery of the radiotracer, amount of radioactivity administered, number and location of injections, and choice of the hand-held probe. We briefly describe the technical and historical aspects of the sentinel node biopsy and summarize the main clinical trials proposed and/or performed in the field.

Sentinel Node Biopsy in Melanoma: The Experience of Brescia Civic Hospital

The accuracy of the sentinel node (SN) technique in the evaluation of lymph node involvement in melanoma was evaluated in 71 consecutive patients with localized disease and Breslow index >1 mm. Lymphoscintigraphy identified at least one SN in 70 of the 71 patients (98.5%). The following day 69 patients underwent selective SN excision. The SN was identified by portable probe. One hundred and twenty-two lymph nodes were removed, 14 (11.4%) of which were metastatic in 9 patients (13%). No metastases were found in 40 patients with Breslow <2 mm. Eight of the 9 patients with positive SNs underwent lymphadenectomy of the whole basin and in two patients new metastatic nodes were found. At 4–26 months’ follow-up 1 of the 60 patients with negative SN (scalp melanoma with Breslow 6.2 mm) developed bilateral cervical metastatic nodes. Two more patients with Breslow 3.7 and 5 mm, respectively, developed liver and lung metastases. The remaining 57 patients are still disease free. Among the 9 patients with tumor-positive SNs, 1 was lost to follow-up, 3 died and 5 are still alive. Our data confirm the clinical reliability of the SN technique in melanoma; we feel the technnique should be considered a standard tool in the evaluation of melanoma patients.

Mapping the Sentinel Lymph Node in Malignant Melanoma by Blue Dye, Lymphoscintigraphy and Intraoperative Gamma Probe

Eighty-eight consecutive patients (48 men and 40 women; mean age, 58.9 years; range, 16–84 years) with clinically localized cutaneous melanoma involving the trunk, extremities or head and neck underwent lymphatic mapping at our institution. The primary melanoma had a mean thickness of 2.74 mm (range, 0.95 to 9 mm). Patients were divided into two groups: group A (39 patients) underwent only vital blue dye (VBD) mapping, while group B (49 patients) underwent lymphatic mapping with VBD and radio-guided surgery (RGS) combined. In all patients 1-1.5 mL of VBD was injected subdermally around the biopsy scar 10–20 min before surgery. In group B 37 MBq in 150 μL of 99mTc-HSA nanocolloid was additionally injected intradermally 18 h before surgery (3–6 aliquots injected perilesionally). In all lymphatic basins where drainage was noted the sentinel lymph nodes (SNs) were identified and marked with a cutaneous marker. Final identification of the SN was then performed externally by a hand-held gamma probe. After the induction of anesthesia 0.5–1-0 mL of patent blue V dye was injected intradermally with a 25-gauge needle around the site of the primary melanoma. SNs were examined by routine hematoxylin and eosin (H&E) staining and immunohistochemistry. Patients with histologically positive SN(s) underwent standard lymph node dissection (SLND) in the involved lymph node basin.

The SN was identified in 37/39 patients (94.9%) of group A and in 48/49 patients (98.0%) of group B. Blue dye mapping failed to identify the SN in 5 of the 88 patients (5.8%), while the radioisotope method failed in only 1 of 49 patients (2.0%). Similar results were obtained with the combined use of the two probes. The average number of SNs harvested was 1.9 per basin sampled, which does not differ significantly from the numbers reported by other authors114. The SN was histologically positive in 18 patients (20.5%). None of the 12 patients with a Breslow thickness less than 1.5 mm had positive SNs, whereas 18 of the 77 patients (23.4%) with a Breslow index exceeding 1.5 mm showed metastatic SNs with H&E or immunohistochemistry. The latter all underwent SLND of the affected basin. In 10 patients (55.6%) the SN was the only site of tumor invasion; eight patients (44.4%) with positive SNs had one or more metastatic lymph nodes in the draining basin.

Morbidity of Selective Lymph Node Biopsy for Melanoma: Meta-Analysis of Complications

Background and Aim

Intraoperative lymphatic mapping and selective lymph node biopsy is accepted worldwide as the standard procedure for staging regional lymph nodes of 1–4 mm thick melanomas, as well as for other neoplasms. Although it is often stated that selective lymph node biopsy is a minimally invasive procedure associated with few complications, few data exist concerning the morbidity associated with the procedure. The present analysis was performed to evaluate the morbidity associated with selective lymph node biopsy in a long-term follow-up.

Materials and Methods

The study provides a review of 437 selective lymph node biopsies on 269 patients, operated on between the 1994 and the 2009, for the lymph node biopsy of head and neck, groin, axilla, upper and lower limbs and nodal basins. Patients’ history and follow-up were reviewed for 2 weeks after surgery, every 3 months for the first 2 years, every 4 months during the third year, and every 6 months subsequently, and postoperative morbidity was evaluated.

Results

After sentinel node biopsy, 14 patients developed one of the following complications: hematoma, 1 case (0.30%); lymphedema, 1 case (0.30%); seroma, 2 cases (0.61%); wound infection, 6 cases (1.83%); keloid scar, 2 cases (0.61%); and postoperative pain, 2 cases (0.61%). The total complication rate was 4.26%.

Conclusions

Selective lymph node biopsy for melanoma, as for other tumors, in respect to radical lymphadenectomy, is not a complications-free procedure but is usually not severe.

Metastases of malignant neoplasms: Historical, biological, & clinical considerations

The metastasis of neoplastic cells from their site of origin to distant anatomic locations continues to be the principal cause of death from malignant tumors, and that fact has been recognized by physicians for over a century. After the work done by Halsted in the treatment of breast cancer in the 1880s, accepted surgical canon held that metastasis occurred in a linear fashion, with centrifugal "growth in continuity" from the primary neoplasm that first involved regional lymph nodes. Those structures were considered to then be the sources of more distant, visceral metastases. With that premise in mind, radical and "ultra-radical" surgical procedures were devised to remove as many lymph nodes as possible in the treatment of carcinomas and melanomas. However, such interventions were ineffective in altering tumor-related mortality. This review considers the details of the historical material just mentioned. It also reviews currently-held concepts on biological mechanisms of metastasis, the "sentinel" lymph node biopsy technique, and the important topic of metastatic tumor "dormancy" as the cause of surgical treatment failure. Finally, predictive models of tumor behavior are discussed, which are based on gene signatures. These will likely be the key to identifying malignant lesions of low surgical stage that ultimately prove fatal through later manifestation of metastasis.

Portable gamma camera guidance in sentinel lymph node biopsy: prospective observational study of consecutive cases

INTRODUCTION

Sentinel lymph node biopsy is the most important tool available for node staging in patients with melanoma.

OBJECTIVES

To analyze sentinel lymph node detection and dissection with radio guidance from a portable gamma camera. To assess the number of complications attributable to this biopsy technique.

METHODS

Prospective observational study of a consecutive series of patients undergoing radioguided sentinel lymph node biopsy. We analyzed agreement between nodes detected by presurgical lymphography, those detected by the gamma camera, and those finally dissected.

RESULTS

A total of 29 patients (17 women [62.5%] and 12 men [37.5%]) were enrolled. The mean age was 52.6 years (range, 26-82 years). The sentinel node was dissected from all patients; secondary nodes were dissected from some. In 16 cases (55.2%), there was agreement between the number of nodes detected by lymphography, those detected by the gamma camera, and those finally dissected. The only complications observed were seromas (3.64%). No cases of wound dehiscence, infection, hematoma, or hemorrhage were observed.

CONCLUSIONS

Portable gamma-camera radio guidance may be of use in improving the detection and dissection of sentinel lymph nodes and may also reduce complications. These goals are essential in a procedure whose purpose is melanoma staging.

Lymphatic mapping and sentinel lymphadenectomy in primary cutaneous melanoma

The management of clinically normal regional lymph nodes in early-stage melanoma has been controversial for over 100 years. Lymphatic mapping and sentinel lymphadenectomy has been developed as a minimally invasive surgical technique to stage regional lymph nodes without the associated morbidity of complete lymph node dissection. Multiple retrospective studies have validated the accuracy of lymphatic mapping and sentinel lymphadenectomy and the importance of the sentinel lymph node as a prognostic tool for melanoma. Several multicenter, prospective, randomized trials are underway to validate the data of the Phase II studies and determine the therapeutic benefit of lymphatic mapping and sentinel lymphadenectomy.

Progression of cutaneous melanoma: implications for treatment

The survival rates of melanoma, like any type of cancer, become worse with advancing stage. Spectrum theory is most consistent with the progression of melanoma from the primary site to the in-transit locations, regional or sentinel lymph nodes and beyond to the distant sites. Therefore, early diagnosis and surgical treatment before its spread is the most effective treatment. Recently, new approaches have revolutionized the diagnosis and treatment of melanoma. Genomic profiling and sequencing will form the basis for molecular taxonomy for more accurate subgrouping of melanoma patients in the future. New insights of molecular mechanisms of metastasis are summarized in this review article. Sentinel lymph node biopsy has become a standard of care for staging primary melanoma without the need for a more morbid complete regional lymph node dissection. With recent developments in molecular biology and genomics, novel molecular targeted therapy is being developed through clinical trials.

Evidence-Based Principles in Pathology: Existing Problem Areas and the Development of “Quality” Practice Patterns

Context.—Contrary to the intuitive impressions of many pathologists, several areas exist in laboratory medicine where evidence-based medicine (EBM) principles are not applied. These include aspects of both anatomic and clinical pathology. Some non-EBM practices are perpetuated by clinical “consumers” of laboratory services because of inadequate education, habit, or overreliance on empirical factors. Other faulty procedures are driven by pathologists themselves.

Objectives.—To consider (1) several selected problem areas representing non-EBM practices in laboratory medicine; such examples include ideas and techniques that concern metastatic malignancies, “targeted” oncologic therapy, general laboratory testing and data utilization, evaluation of selected coagulation defects, administration of blood products, and analysis of hepatic iron-overload syndromes; and (2) EBM principles as methods for remediation of deficiencies in hospital pathology, and implements for the construction of “quality” practices in our specialty.

Data Sources.—Current English literature relating to evidence-based principles in pathology and laboratory medicine, as well as the authors' experience.

Conclusions.—Evidence-based medicine holds the promise of optimizing laboratory services to produce “quality” practices in pathology. It will also be a key to restraining the overall cost of health care.

The impact of primary melanoma thickness and microscopic tumor burden in sentinel lymph nodes on melanoma patient survival

BACKGROUND

The primary objectives of this work are to (1) quantitate tumor burden in sentinel lymph nodes (SLNs), and (2) assess the independent contributions of SLN tumor burden and primary melanoma thickness (PMT) with respect to progression-free survival (PFS) and overall survival (OS).

METHODS

Sixty-three patients (41 male and 22 female) with one or more positive SLNs were available for review in this study, with median follow-up of 6.8 years. PMT was measured and SLN metastases were assessed for size, as maximum metastasis size (MMS) in mm, by hematoxylin and eosin (H&E) and immunohistochemistry (S100 and HMB45). PFS and OS were calculated from time of SLN resection until melanoma recurrence or death. Univariate and multivariate analyses and trend test were performed.

RESULTS

Kaplan-Meier estimates of PFS and OS differed significantly by MMS (log-rank P = 0.031 for PFS and P = 0.016 for OS) and PMT (log-rank P = 0.036 for PFS and P < 0.001 for OS). After adjusting for age and gender, the hazard ratio (HR) associated with MMS was 1.09 per mm increase (P = 0.05) for PFS, and 6.30 (P = 0.014) and 5.41 (P = 0.048) for OS in patients, respectively, with MMS of 0.6-5.5 mm and MMS ≥5.5 mm compared with those with MMS <0.6 mm. When patients were stratified by their tumor characteristics of PMT, the risk for disease progression and worse OS was substantially higher for the group with PMT ≥ 4.5 mm (HR = 13.10 and P = 0.022 for PFS; HR = 17.26 and P < 0.001 for OS) relative to the baseline group with PMT <1.6 mm. All patients had completion lymph node dissection (CLND) except for four patients. Patients with positive CLND (14, 22.2%) showed significant worse PFS (P = 0.002) and OS (P = 0.0003) than the negative CLND group (45, 71.4%).

CONCLUSIONS

PMT and MMS were independently prognostic of PFS and OS in melanoma patients. Patients with negative CLND had significantly better PFS and OS than those with positive CLND.

Surgical management of melanoma

Melanoma is an increasing health care problem worldwide. Up to 80,000 cases of melanoma are diagnosed per year and it is the sixth leading cause of cancer death in the United States. The lifetime risk is estimated to be 1 in 75 individuals for the development of melanoma. Surgery remains the mainstay of treatment of melanoma, and in most cases it is curative. Several important surgical issues are discussed in this review, including the extent of surgical margins, Mohs micrographic surgery for melanoma in situ, the use of sentinel lymph node biopsy, the usefulness of lymphadenectomy, isolated limb perfusion, and the role of metastasectomy.

Cutaneous melanoma in the elderly

The aim of this review was to analyze the difficulties in diagnosing and treating elderly patients with cutaneous melanoma. It focused on the main causes for late diagnosis and relatively poor prognosis in these patients. Early detection of melanoma is vital to reduce mortality in these patients and surgery is often curative. Adequate treatment of elderly patients with melanoma requires knowledge of the clinical features and histopathology of the disease, and the therapeutic options. This review also examined the main surgical procedures for primary melanoma and regional lymph node staging, and the curative and palliative procedures indicated for those elderly patients with advanced disease. It is expected that several molecular genetic factors will soon provide further prognostic information of possible benefit for elderly patients with melanoma.

Comparison of metallothionein-overexpression with sentinel lymph node biopsy as prognostic factors in melanoma

BACKGROUND

Metallothioneins (MT) are ubiquitous, intracellular small proteins with high affinity for heavy metal ions. Immunohistochemical MT overexpression in paraffin-embedded tissues of patients with primary melanoma is associated with poor prognosis. While sentinel lymph node (SLN) biopsy is an established surgical technique for high-risk melanoma patients with predictive value for progression, the benefit of this procedure for the individual patient's overall survival remains unclear.

AIM AND METHODS

We examined the role of MT overexpression in comparison with SLN biopsy in melanoma patients as a prognostic marker for progression and survival. One hundred and fifty-eight (158) patients underwent SLN biopsy due to high-risk melanoma. Primary melanoma specimens were investigated by using a monoclonal antibody against MT on routinely fixed, paraffin-embedded tissues. The patients were followed up (median 37 months); the data of disease free survival and overall survival were calculated with a broad panel of statistical analyses.

RESULTS

Twenty-eight (18%) out of 158 recruited melanoma patients developed metastases, 17 (11%) patients died due to widespread disease. Kaplan-Meier curves gave significant disadvantages for the MT-positive as well as the SLN-positive group for progression and survival. In the Fisher's exact test and Pearson's chi(2)-test MT overexpression was highly significant for progression, whereas SLN biopsy failed significance. In univariate as well as multivariate Cox regression analysis MT overexpression proved an excellent marker for progression (P=0.007 and P=0.009), although the P-values for survival were not significant. In contrast, while in the univariate analysis SLN biopsy did not show significant results for progression it did for survival, and in the multivariate analysis reached a P-value < 0.05 for both measured endpoints.

CONCLUSION

Results corroborate the validity of MT overexpression in primary melanoma as a useful prognostic marker in melanoma patients. Accuracy is comparable and to some degree supplementary to the results of SLN biopsy.

Malignant melanoma in the 21st century, part 2: staging, prognosis, and treatment

Critical to the clinical management of a patient with malignant melanoma is an understanding of its natural history. As with most malignant disorders, prognosis is highly dependent on the clinical stage (extent of tumor burden) at the time of diagnosis. The patient's clinical stage at diagnosis dictates selection of therapy. We review the state of the art in melanoma staging, prognosis, and therapy. Substantial progress has been made in this regard during the past 2 decades. This progress is primarily reflected in the development of sentinel lymph node biopsies as a means of reducing the morbidity associated with regional lymph node dissection, increased understanding of the role of neoangiogenesis in the natural history of melanoma and its potential as a treatment target, and emergence of innovative multimodal therapeutic strategies, resulting in significant objective response rates in a disease commonly believed to be drug resistant. Although much work remains to be done to improve the survival of patients with melanoma, clinically meaningful results seem within reach.

The role of sentinel lymph node biopsy in the management of melanoma

During the last 2 decades, the development and wide acceptance of SLN biopsy have affected the management of melanoma profoundly. This technique represents a considerable improvement in the ability to evaluate the tumor status of the regional lymph node basin, which is the most important predictor of survival in patients who have melanoma. Histopathologic and molecular assessment of the SLN has enhanced the detection of clinically occult nodal metastases, thereby distinguishing patients who might benefit from immediate lymphadenectomy from those for whom this procedure is unlikely to be helpful. This technique also identifies patients who would be candidates for clinical trials of adjuvant therapy. Centers can offer SLN biopsy without routine CLND once they reach a level of proficiency that usually corresponds to a learning phase of 55 cases. The role of molecular technology in the identification and analysis of the SLN remains to be established. Although molecular evidence of SLN metastasis has been identified in patients who have early-stage melanoma, its clinical relevance cannot be determined until marker selection is improved. The markers presently under study lack sensitivity and specificity. The role of molecular biomarkers can be validated only through large, multicenter, randomized. controlled trials such as the MSLT-II, a trial that will determine the benefit of multimarker RT-PCR assay in SLN specimens. SLN offers a promising future in staging lymph nodes and will improve the management of patients who have melanoma. Although SLN biopsy has become widely accepted as a minimally invasive technique of staging regional lymph nodes, its use in patients who have melanoma continues to be challenged. The future of SLN biopsy holds promise if prospective multicenter trials confirm a survival benefit for SLN biopsy as compared with watch-and-wait observation.

[Intraoperative labeling of sentinel lymph nodes with a combination of vital dye and radionuclide tracer--results in sentinel lymph node-positive patients]

BACKGROUND

Sentinel lymph node biopsy enhances the accuracy of tumor staging in patients with malignant melanoma and can help select candidates for regional lymphadenectomy. There are two techniques for identifying the sentinel lymph node: intradermal injection of a radionuclide tracer or of a blue dye. We evaluated both methods to determine how they can be best utilized to locate a sentinel lymph node.

PATIENTS AND METHODS

In a retrospective study, 323 patients with melanoma (tumor thickness > or = 0.75 mm) who underwent sentinel lymph node biopsy after both radionuclide and blue dye injection were evaluated. The labeling of lymph nodes showing micrometastasis by histopathological examination was determined.

RESULTS

63 patients showed sentinel lymph nodes with micrometastasis. All of these nodes (100 %) were labeled with radionuclide tracer, but only 90 % with blue dye. In 5 patients, only radionuclide labeling identified the histopathologically-positive lymph node. In 36 patients, several sentinel lymph nodes were identified, with the histopathologically-positive nodes usually showing a higher radioactive signal intensity than the negative ones.

CONCLUSION

Since in some patients histopathologically-positive lymph nodes are only labeled by radionuclide tracer, radionuclide labeling is indispensable for locating sentinel lymph nodes. In contrast, labeling with blue dye represents a supplementary method, which can simplify the recognition of the sentinel lymph node during surgery.

Sentinel lymph node status in melanoma: a valuable prognostic factor?

BACKGROUND

Sentinel lymph node (SLN) biopsy is advocated as the standard of care for patients with primary melanoma. It is a procedure with few side-effects and provides valuable staging information about the regional lymphatics.

OBJECTIVES

To investigate the prognostic value of SLN biopsy and to compare it with that of other known risk factors in primary melanoma.

METHODS

One hundred and forty-nine patients with primary melanomas (tumour thickness >1.0 mm) underwent SLN biopsy between May 1998 and April 2004 at our department. This report summarizes the follow-up data of this cohort until October 2004.

RESULTS

SLN biopsies of 49 of 149 patients (33%) revealed micrometastatic disease. Of all clinical and histological criteria, only the clinical type of primary melanoma (11 of 19 patients with acrolentiginous melanomas) and the Clark level were predictive for SLN positivity. Progression was observed in 22 patients (15%). It was significantly associated with ulceration of the primary tumour, tumour thickness, clinical type and localization of the primary tumour, female sex and older age. In contrast, SLN positivity was not significantly associated with a higher risk of progression (eight of 49 SLN-positive vs. 14 of 100 SLN-negative patients; P = 0.807). Twelve of 149 patients (8%) died because of melanoma in the follow-up period. Significant criteria for death were ulceration of the tumour, clinical type and localization of the primary tumour, but not SLN positivity.

CONCLUSIONS

A high percentage of positive SLNs was observed in the patients with melanoma in our study (33%). The fractions of patients both with progressive disease and with tumour-related death were not significantly higher in patients with positive SLN than in those with negative SLN. We therefore conclude that the SLN status is not a reliable prognostic factor for progression of melanoma.

Vital dye is enough for inguinal sentinel lymph node biopsy in melanoma patients

PURPOSE

The importance of gamma probe detection (GPD) combined with vital dye for sentinel node (SN) biopsy is well accepted. We evaluated the efficacy of patent blue dye (PBD) in identifying inguinal SN.

METHODS

Ninety-four cutaneous melanoma patients with inferior extremity lesions were submitted to SNB according to a established protocol. Patients were randomized in two groups: Blue group, where SN was identified by PPD and Probe group, where SN was identified by GPD. The median age was 44.2 years and median Breslow thickness was 2.1 mm. Preoperative lymphoscintigraphy, lymphatic mapping with PBD and intra-operative GPD was performed on all patients. Histological examination of SN consisted of hematoxylin-eosin and immunohistochemical staining. If micrometastases were present complete lymphadenectomy was performed. The SN was considered as identified by PBD if it was blue and identified by GPD if it demonstrated at least ten times greater radioactivity than background.

RESULTS

It was explored 94 inguinal lymphatic basins, 145 SN were excised (70 guided primarily by blue dye and 75 guided primarily by probe). All SN identified by preoperative lymphoscintigraphy were excised. In the Blue group PPD identified all SN and all of them were hot. In the Probe group all SN were identified by probe and were blue. The coincidence of PPD and GPD was 100%.

CONCLUSION

Patent blue dye is enough to identify superficial inguinal SN in cutaneous melanoma.

Clinical significance of occult metastatic melanoma in sentinel lymph nodes and other high-risk factors based on long-term follow-up

Selective sentinel lymphadenectomy (SSL) following preoperative lymphoscintigraphy is the most significant recent advance in the management of patients with primary melanoma. This study evaluates the prognostic value of sentinel lymph node (SLN) status and other risk factors in predicting survival and recurrence in patients with primary cutaneous melanoma. From October 1993 to July 1998 a series of 412 patients with primary invasive melanoma underwent SSL at the UCSF/ Mt. Zion Melanoma Center. The outcome of 363 evaluable patients is summarized in this study. The factors related to survival and disease recurrence were analyzed by Cox proportional hazard regression models. The overall incidence of patients with positive SLNs was 18%. Over a median follow-up of 4.8 years, the overall mortality rate in patients with primary cutaneous melanoma was 18.7%, and 74 recurrences occurred (20.4%). Mortality was significantly related to SLN status [HR = 2.06; 95% Confidence interval (CI) 1.18, 3.58], angiolymphatic invasion (HR = 2.21; 95% CI 1.08, 4.55), ulceration (HR = 1.79; 95% CI 1.02, 3.15), mitotic index (HR =1.38; 95% CI 1.01, 1.90), and tumor thickness (HR = 2.20, 95% CI 1.21, 3.99). Factors significantly related to disease-free survival included SLN status (HR = 2.09; 95% CI 1.31, 3.34), tumor thickness (HR = 1.89; 95%. CI 1.20,2.98), and age (HR= 1.26 95% CI 1.08, 1.47). SLN status was the most significant factor for melanoma recurrence and death. Other important predictors include tumor thickness, ulceration, lymphatic invasion, and mitotic index.

The first description of sentinel node biopsy in a patient with amelanotic melanoma of the glans penis

We present the first description of sentinel node biopsy in a patient with amelanotic melanoma of the glans penis. The patient underwent partial amputation of the penis due to tumor of the glans. Pathologic examination of the postoperative specimen revealed the presence of a very rare malignancy--amelanotic melanoma. Sentinel node biopsy, with the use of the combined radiotracer/blue dye technique, was performed. Preoperative lymphoscintigraphy was performed the day before surgery. During surgery, blue dye mapping and intraoperative detection of gamma radiation were used. Two sentinel nodes were identified in the left inguinal region and one sentinel node in the right inguinal region. All sentinel nodes were an intense violet color; in each case, the level of radiation in the sentinel node was almost 20 times higher than the level of radiation in the node bed. Routine hematoxylin and eosin staining and immunohistochemistry (HMB-45) revealed the presence of micrometastasis in one of the sentinel nodes harvested from the left inguinal region. Consequently, left inguinal, iliac and obturatory lymphadenectomies were performed. The final pathologic examination revealed the presence of one metastasis (diameter, 2 mm) in one of the resected non-sentinel nodes. No relapse has been observed during 18 months of follow-up.

Lymphatic mapping and sentinel node biopsy: a surgical perspective

Lymphatic mapping and sentinel node biopsy has been rapidly and widely adopted by the surgical community as an oncologic equivalent elective lymphadenectomy for regional node staging in both melanoma and breast cancer. Despite being the de facto standard of care, it remains a highly unstandardized procedure surrounded by many unresolved controversies for surgeons who perform the procedure. The controversies are as basic as the definition of the real sentinel node and as specific as the appropriate localization pharmaceutical(s), site of injection, timing of the injection, and utility of external scintigraphy (dynamic versus. static). Furthermore, questions regarding surgical training, indications, and contraindications remain unanswered. Because there are few long-term studies stratified by technique and indication, the resolution of these surgical controversies are unlikely in the near future.

Clinical and biological aspects of sentinel node biopsy in malignant melanoma — an update

The diagnostic usefulness of sentinel lymph node biopsy (SLNB) has been well established, but its therapeutic value remains unproven. First introduced by Morton and colleagues, the SLNB procedure is now widely available, and markedly enhances our ability to pathologically stage the regional nodes. Although the SLN status is acknowledged as the most powerful indicator of prognosis in melanoma, there is no evidence to-date, of survival advantage for complete lymphadenectomy in SLN-positive patients. Also, there is no effective adjuvant therapy that could benefit these sentinel node-positive patients, as yet. Additionally, new data have emerged indicating a possible increase in local/in-transit recurrence following complete lymphadenectomy in sentinel node-positive patients. To understand fully and to evaluate these observations we need information from randomized controlled trials. Major changes have occurred following the latest revision of melanoma staging system (AJCC, 6th edition). Concerning N category, these include the incorporation of the number of metastatic lymph nodes, the tumour burden of nodal metastases, and the ulceration of the primary tumour. The data obtained from the new staging system will reflect differences in prognosis that were not previously emphasized and which, we hope, will serve as a guide to more accurate analysis of metastatic pathways in cutaneous melanoma as well as a rationale for new forms of treatment.

Evidence-based principles and practices in pathology: selected problem areas

Contrary to the intuitive impression of most pathologists, there are still many areas in laboratory medicine where evidence-based medicine (EBM) principles are not applied. These include aspects of both anatomic and clinical pathology. Some non-EBM practices are perpetuated by clinical "consumers" of laboratory services, because of inadequate education, habit, or over-reliance on empirical factors. Other faulty procedures are pathologist-driven, with similar underpinnings. This overview considers several exemplary problem areas representing non-EBM practices in the hospital laboratory. Such examples include ideas and techniques centering on metastatic malignancies, "targeted" oncological therapy, analysis of surgical margins in the excision of neoplasms, general laboratory testing and data utilization, evaluation of selected coagulation defects, administration of blood products, and analysis of hepatic iron-overload syndromes. The concepts illustrating departures from EBM are discussed for each of those topics.

Sentinel lymph node biopsy in head and neck cancer

Sentinel lymph node biopsy (SLNB) offers a minimally invasive technique to examine the proximal lymph node basin for micrometastases in clinically N0 necks in patients head and neck cancer. This technique has been validated in the management of breast cancer and cutaneous malignant melanoma (CMM) and is under active investigation in the management of multiple other solid tumors.SLNB is used routinely in the management of head and neck melanoma and is investigational for other cancers of the head and neck. SLNB provides prognostic information for patients with CMM and identifies those patients that may benefit from additional treatment. This article examines the history, rationale,science, and current status of SLNB in head and neck with emphasis on melanoma.

Selective sentinel lymphadenectomy for malignant melanoma, Merkel cell carcinoma, and squamous cell carcinoma

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). An SLN is defined as a blue, "hot" and any subsequent lymph node greater than 10% of the ex vivo count of the hottest lymph node. Any enlarged or indurated lymph node in the nodal basin should be excised. 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 the surgery can be scheduled as the first case of the following day. Every surgeon who uses blue dye should be aware 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 (ELND) should not be done if an SSL can be performed as a staging procedure. SSL has further been applied to stage the nodal basin for Merkel cell carcinoma and high-risk squamous cell carcinoma. It is important for investigators involved with the SSL to follow the clinical outcome of these patients, so that the role of SSL can be further defined.

Diagnosis of melanoma in the elderly and surgical implications

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

Sentinel-lymph-node biopsy (SLNB) for melanoma is not complication-free

BACKGROUND AND AIM

Sentinel lymph node biopsy (SLNB) is reportedly associated with insignificant morbidity. The study aims at documenting SLNB-related complications and identifying possible risk factors.

METHOD

Data of all melanoma patients who underwent SLNB in our medical center (1994-2002) were analysed. Procedure-related complications were recorded.

RESULTS

Three hundred and nine lymphatic basins of 250 patients were explored for SLNB. Overall complication rate was 20%. Sensory morbidity was significantly associated with axillary SLNB (p=0.04) and was more prevalent in younger patients. The use of blue dye alone or combined with a hand-held gamma probe had no statistically significant impact on the identification rate. There were six false-negatives (2.3%), for an overall false-negative rate of 18%. A positive sentinel node was significantly associated with shortened overall survival (p=0.04).

CONCLUSION

Wound complications are more frequent than usually reported. Sensory morbidity occurs mostly in the axilla. Neck SLNB is associated with the highest rate of identification failure. Patient age, basin location, and number of excised nodes may serve as prognostic factors of morbidity.

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 mapping and selective lymphadenectomy: the standard of care for melanoma

Selective sentinel lymphadenectomy (SSL) should be considered a standard of care approach for staging patients with primary invasive melanoma 1 mm or greater. It is essential that multidisciplinary teams should master the techniques of preoperative lymphoscintigraphy, intraoperative lymphatic mapping, and pathologic evaluation of the sentinel lymph nodes (SLNs). An SLN may be blue, hot, or any lymph node (LN) greater than 10% of the in-vivo count of the hottest LN. An enlarged or indurated LN should be removed because it may contain metastatic cancer cells that block blue dye or radiotracer entry. Frozen sections are not recommended. Surgeons who use isosulfan blue dye should be cognizant of treatment for a potentially fatal reaction. Prophylactic LN dissection should not be performed if a SSL can be performed as a staging procedure. A complete LN dissection is performed if the SLN is positive. It is important to follow the clinical outcome of patients undergoing SSL, thus its role can be further defined.

Sentinel node biopsy procedures with an analysis of recurrence patterns and prognosis in melanoma patients: technical advantages using computer-assisted gamma probe with adjustable collimation

The purpose of this study was to investigate whether a computer-assisted gamma probe with adjustable collimation could aid in the detection of sentinel nodes (SNs) and to analyse the patterns of recurrence and prognosis in SN-positive and SN-negative cases. We analysed 385 SN biopsies. The SN identification rate was 87.2% using preoperative lymphoscintigraphy and blue dye, 93.9% using preoperative lymphoscintigraphy, blue dye and different probes, and 100% using preoperative lymphoscintigraphy, blue dye and a computer-assisted probe with adjustable collimation. The computer-assisted probe was particularly advantageous in cases where the melanoma was located very close to the SN and in cases of deep-seated nodes or nodes with low uptake, due to the possibility of changing the collimation during the procedure. The SN-positive rate according to the thickness of the primary melanoma was 1.7% for melanomas < or = 1 mm in thickness and 27.5% for melanomas > or = 1 mm. In 4.9% of cases we identified nodes outside the regional nodal basin. In one case we found a micrometastasis in a blue and hot interval node of the lateral abdominal wall. Analysing the node counts registered by the computer-assisted probe, we verified that the blue-positive node for tumour metastases was not the most radioactive node in the field in six out of 52 positive cases (11.5%). Distant metastases were present in 2.0% of SN-negative patients, and in 24% of SN-positive patients (P < 0.001). Highly statistically significant differences were found between SN-negative and SN-positive patients in both the 3 year disease-free survival (86.3% versus 49.2%) and the 3 year disease-specific survival (92.3% versus 77.1%) (P < 0.001).

Sentinel lymph node biopsy progress in surgical treatment of cancer

BACKGROUND

Forty-three years after the first description of the sentinel lymph node technique in malignant tumours of the parotid by Gould, sentinel lymph node biopsy (SNLB) has become a precious tool in the treatment of solid tumours.

METHODS

In the following review we give a synopsis of the fundamentals of the sentinel lymph node concept and then proceed to an overview of recent advances of SNLB in gastrointestinal cancers.

RESULTS

In some tumour entities, SNLB has been shown to reflect reliably the lymph node status of the tumour-draining lymph node basin. In melanoma and breast cancer, it became a widely accepted element of the routine surgical management of these malignant diseases. In gastrointestinal tumours, the technique is currently under intense investigation. First reports on its application in other solid tumours, such as non-small cell lung cancer, thyroid carcinoma, oropharyngeal carcinoma, vulvar carcinoma, and Merckel cell carcinoma of the skin, were published more recently.

CONCLUSION

SNLB has become an important component of diagnosis and treatment of solid tumours. A growing number of publications on SNLB in gastrointestinal cancer documents the interest of many investigators in the application of this technique in this tumour entity. As long as imaging techniques like 18FDG PET or other molecular imaging techniques are limited by their spatial resolution, SNLB remains the technique of choice for lympho-nodal staging.

Sentinel lymph node biopsy

The introduction of sentinel lymph node biopsy (SLNB) has been an important development in the management of malignant melanoma. Lymph nodes have long been known to play a key role in melanoma metastasis. The importance of nodal staging accounted for the previous surgical practice of elective lymph node dissection (ELND) even with its controversial impact on final outcomes and associated morbidity. Although this morbidity has been reduced with the ability to identify the SLN, numerous questions have subsequently surfaced with respect to this procedure's utility and therapeutic efficacy. This chapter will focus on the indications for SLNB, as well as the current controversies surrounding this procedure.

Sentinel lymph node detection in primary melanoma with preoperative dynamic lymphoscintigraphy and intraoperative γ probe guidance

Background

This study assessed the value of the radioisotopic method used alone, and factors influencing relapse rates, for sentinel lymph node (SLN) mapping in primary melanoma.

Methods

One hundred and thirty-three patients with a diagnosis of melanoma (thickness greater than 0·75 mm) underwent γ probe-directed lymphatic mapping in a prospective single-centre study.

Results

Mean Breslow thickness was 3 mm. At least one SLN was identified in 132 patients (mean 1·8 nodes per patient); the success rate was 99·2 per cent. Twenty-two patients (16·7 per cent) had a metastasis within the SLN. The mean tumour thickness in patients with a metastatic SLN was 4·4 mm compared with 2·7 mm for patients with a negative SLN (P &lt; 0·001). The median time to recurrence was 20·4 months in SLN-negative patients compared with 8·5 months in those with SLN metastasis (P &lt; 0·001). Ten (9·1 per cent) of the 110 SLN-negative patients developed recurrence. Three patients relapsed in the previously mapped lymphatic basin after a median follow-up of 27·1 months.

Conclusion

This study confirmed the reliability and accuracy of SLN mapping using a radioisotope technique, and also the importance of the SLN as a predictive factor for survival. There was a low risk of locoregional recurrence when the SLN was not involved.