Reliability of sentinel lymph node biopsy for staging melanoma

Current Treatment Strategies and Risk Stratification for Oral Carcinoma

Management of oral cavity squamous cell carcinoma (OSCC) involves a multidisciplinary team approach. Surgery is ideally the primary treatment option for nonmetastatic OSCC, and less invasive curative surgical approaches are preferred in early-stage disease to minimize surgical-related morbidity. For patients at high risk of recurrence, adjuvant treatment using radiation therapy or chemoradiation is often used. Systemic therapy may also be used in the neoadjuvant setting (for advanced-stage disease with the intent of mandibular preservation) or in the palliative setting (for nonsalvageable locoregional recurrence and/or distant metastases). Patient involvement in treatment decision is the key for patient-driven management, particularly in clinical situation with poor prognosis, for example, early postoperative recurrence before planned adjuvant therapy.

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.

Predictive and Prognostic Value of BRAF and NRAS Mutation of 159 Sentinel Lymph Node Cases in Melanoma-A Retrospective Single-Institute Study

PURPOSE

To assess the prognostic role of sentinel lymph node status (SLN) in melanoma patients, a statistical comparison was performed with the application of already known prognostic factors, mutational occurrence of BRAF and NRAS in the primary tumor, as well as disease outcome.

METHODS

Our retrospective single-center study involved 159 melanoma cases, who underwent SLN biopsy. The following clinico-pathological data were collected: age, gender, location of primary tumor, Breslow thickness, ulceration degree, histological subtype, mitosis count, lymphovascular and perineural invasion, presence of tumor-infiltrating lymphocytes, regression signs, mutations of BRAF and NRAS of the primary tumors, and SLN status.

RESULTS

From the studied clinico-pathological factors, only Breslow thickness increased the risk of SLN positivity (p = 0.025) by multivariate analysis, while neither BRAF nor NRAS mutation of the primary tumor proved to be a predictor of the SLN status. While the NRAS-mutant subgroup showed the most unfavorable outcome for progression-free and distant metastasis-free survival, their rate of positive SLNs proved to be relatively lower than that of patient groups with BRAF mutation and double-wild-type phenotypes.

CONCLUSION

Similarly to the importance of SLN positivity, NRAS mutation of the primary tumor proved to be an independent prognostic factor of progression. Therefore, despite negative SLN, this NRAS-mutant subgroup of patients still requires closer monitoring to detect disease progression.

Sentinel lymph node biopsy in patients with malignant melanoma: analysis of post-operative complications

BACKGROUND

This study investigates the incidence of post-operative complications and risk factors of sentinel lymph node biopsy (SLNB) in melanoma patients.

METHODS

A retrospective cohort study was conducted at a single cancer institution on 408 consecutive SLNBs.

RESULTS

Fifty-five post-operative complications occurred in 39 (9.5%) patients and included: wound infection in 24 (5.9%), seroma and lymphorrhea in 15 (3.7%), wound dehiscence in seven (1.7%), lymphocele in six (1.5%) and others in three (0.7%). Univariate analysis failed to identify possible risk factors (i.e. gender, age, lymph node region, number of excised lymph nodes, Breslow index, pT levels, comorbidities, length of surgery and hospital stay). Metastatic sentinel nodes occurred in four of 135 (3%) patients with thin melanoma (Breslow <1 mm) and in 68 of 262 (25.9%) patients with Breslow >1 mm.

CONCLUSION

For patients with thin melanoma in whom the incidence of lymph node metastasis is low, the reported post-operative morbidity of almost 10% of SLNB highlights the need for careful patient selection.

Trends in Sentinel Lymph Node Biopsy Enactment for Cutaneous Melanoma

BACKGROUND

Over recent years, sentinel lymph node biopsy (SLNB) recommendations in guidelines for cutaneous melanoma have changed considerably. We aimed to assess trends in enactment of SLNB to evaluate to what extent guidelines were adhered to, and to identify clinical and pathological determinants of (non-)adherence.

METHODS

Clinicopathological data from the Dutch nationwide network and registry of histopathology and cytopathology were retrieved from patients diagnosed with primary cutaneous melanoma in The Netherlands between 2003 and 2014. SLNB enactment was analyzed per year. Multivariable regression models were developed to assess the determinants of SLNB enactment.

RESULTS

A total of 51,510 primary cutaneous melanomas in 49,514 patients were diagnosed, of which 24,603 melanomas were eligible for SLNB as they were staged T1b or higher. In practice, only 9761 (39.7%) patients underwent SLNB, with an increasing trend from 39.1% in 2003 to 47.8% in 2014 (p < 0.001). A total of 759 (2.9%) of 26,426 patients without SLNB indication underwent SLNB anyway. Variables significantly associated with enactment of SLNB were male sex, younger age, and melanoma on sites other than the head and neck.

CONCLUSIONS

Although there was an increasing trend in time in SLNB enactment, enactment of SLNB did not comply well with recommendations in (inter)national guidelines. Female sex, higher age, and melanoma located on the head and neck were associated with non-enactment of SLNB.

Role of sentinel lymph node biopsy as a staging procedure in patients with melanoma: A critical appraisal

Worldwide, sentinel node (SN) biopsy for accurate staging is now part of the standard work-up of patients with melanomas ≥1.0 mm Breslow thickness, as it is for staging patients with breast cancer. Nuclear medicine imaging and surgical techniques have evolved to such a degree that a SN can be identified and removed in virtually every patient. Nevertheless, some opposition to a routine SN biopsy remains, perhaps due to a failure to appreciate the serious implications of incomplete or inaccurate staging. Guided by a critical appraisal of the available evidence, this review elucidates the definition of an SN, discusses the sensitivity and specificity of the information it provides, emphasises that it is a minor staging procedure that can lead to improved survival when followed by appropriate therapy, and explains the necessarily unconventional and complex design of the only randomised trial that addresses this subject. It also describes other benefits and risks of an SN biopsy and outlines its role in current melanoma management.

Is sentinel node susceptibility to metastases related to nodal immune modulation?

Sentinel lymph nodes (SLNs), the initial site of regional metastases, directly receive lymph containing immune-modulatory cytokines and tumor cells from primary melanomas. Immune-suppressed SLNs are ideal for studies of tissue susceptibility to metastases. They show reduced antigen-presenting dendritic cells, activated T cells, high endothelial venules, and transvenular immigration of T cells. Tumor-induced immune suppression contributes to establishment of nodal metastases. SLNs may serve as an effective model to study reversal of tumor-induced immune suppression. We reviewed this topic in Nature Reviews of Immunology in 2006. We here summarize the Nature paper and provide additional results from ongoing studies and the recent literature.

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.

Sentinel lymph node biopsy and survival in elderly patients with cutaneous melanoma

BACKGROUND

Sentinel lymph node biopsy (SNB) is a widely adopted staging procedure in patients with cutaneous melanoma. The benefits of SNB have not been evaluated thoroughly in older age groups.

METHODS

This was a two-centre retrospective observational study of patients with melanoma aged at least 70 years undergoing SNB.

RESULTS

A total of 423 patients were included. SNB was successful in 405 patients (95·7 per cent), of whom 88 (21·7 per cent) had sentinel node metastasis. During a median follow-up of 2·5 years, recurrence developed in 80 patients (18·9 per cent). Nodal recurrence developed in eight sentinel node-negative patients, giving a false-negative rate of 8·3 per cent, a sensitivity of 91·7 per cent and an overall diagnostic accuracy of 98·0 per cent. A total of 46 patients (10·9 per cent) died from melanoma and 42 (9·9 per cent) from other causes. At 5 years, the relapse-free survival rate was 80·0 per cent in sentinel node-negative patients and 39 per cent in node-positive patients; cancer-specific survival rates were 88·6 per cent and 46 per cent respectively (P < 0·001). In multivariable analysis, sentinel node metastasis (P < 0·001), a Breslow thickness of at least 2·0 mm (P = 0·007) and presence of ulceration (P = 0·012) were independent prognostic factors for cancer-specific survival.

CONCLUSION

SNB is a feasible and accurate technique for detecting nodal metastases in older patients with melanoma. Sentinel node status is the most important predictor of cancer-specific outcome in the elderly.

Histologically ambiguous ("borderline") primary cutaneous melanocytic tumors: approaches to patient management including the roles of molecular testing and sentinel lymph node biopsy

It is well recognized that the pathologic diagnosis of melanocytic tumors can sometimes be difficult. For some atypical melanocytic tumors that do not display clear-cut features of malignancy, it may be difficult or impossible to exclude a diagnosis of melanoma; this includes those showing some resemblance to Spitz nevi, blue nevi, deep penetrating nevi, and possible nevoid melanomas. When there is uncertainty about whether a primary melanocytic tumor is a nevus or a melanoma, we recommend that a second opinion be sought from one or more experienced colleagues. If diagnostic uncertainty persists, the evidence for or against the various differential diagnostic considerations should be presented in the pathology report and a "most likely" or "favored" diagnosis given. Molecular testing of the primary tumor by using techniques such as comparative genomic hybridization or fluorescence in situ hybridization may assist in establishing a diagnosis of melanoma if multiple chromosomal aberrations are identified. However, these tests require further independent validation and are not widely available at present. Complete excision of the lesion is probably mandatory, but plans for further management should be formulated on a case-by-case basis. While the safest course of action will usually be to manage the tumor as if it were a melanoma (taking into account the tumor's thickness and other prognostic variables), this may not always be appropriate, particularly if it is located in a cosmetically sensitive site such as the face. In some cases, it may be appropriate for the surgical oncologist to convey the diagnostic uncertainty to patients and to present them with management choices so that they can decide whether they wish to be managed aggressively (as for a melanoma) or conservatively. While a sentinel lymph node biopsy may be recommended on the basis of the primary tumor characteristics, the clinical significance of lymph node involvement for these tumors is not yet clear, and it may not have the same prognostic implications as nodal involvement from an unequivocal "conventional" melanoma.

Importance of tumor load in the sentinel node in melanoma: clinical dilemmas

There are two hypotheses to explain melanoma dissemination: first, simultaneous lymphatic and hematogeneous spread, with regional lymph nodes as indicators of metastatic disease; and second, orderly progression, with regional lymph nodes as governors of metastatic disease. The sentinel node (SN) has been defined as the first draining lymph node from a tumor and is harvested with the use of the triple technique and is processed by an extensive pathology protocol. The SN status is a strong prognostic factor for survival (83-94% for SN negative, 56-75% SN-positive patients). False-negative rates are considerable (9-21%). Preliminary results of the MSLT-1 trial did not demonstrate a survival benefit for the SN procedure, although a subgroup analysis indicates a possible benefit. A mathematical model has demonstrated 24% prognostic false positivity. SN tumor burden represents a heterogeneous patient population and is classified most frequently with the Starz, Dewar or Rotterdam Criteria. A completion lymph-node dissection might not be indicated in all SN-positive patients. Patients classified with metastases <0.1 mm by the Rotterdam Criteria have excellent survival rates. Ultrasound-guided fine-needle aspiration cytology is emerging as a staging tool for high-risk patients, but more research is necessary before this can change clinical practice.

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.

Interobserver reproducibility of histologic parameters of melanoma deposits in sentinel lymph nodes: implications for management of patients with melanoma

BACKGROUND

: Histologic parameters of melanoma deposits in sentinel lymph nodes (SLNs) have been shown to be predictive of clinical outcome and the presence or absence of tumor in non-SLNs, but assessment of these parameters is prone to interobserver variation.

METHODS

: Histologic sections of 44 SLNs containing metastatic melanoma were examined by 7 pathologists. Parameters assessed included cross-sectional area of tumor deposits, cross-sectional area of SLNs, percentage of SLN area involved by tumor calculated from the 2 previous parameters, estimated percentage of SLN area involved by tumor, tumor penetrative depth, location of tumor within the SLN, and presence of extracapsular spread. Levels of interobserver agreement were measured by using intraclass correlation coefficients (ICC).

RESULTS

: There was good to excellent interobserver agreement on measurement of quantitative parameters: maximal size of largest tumor deposits, calculated area of 3 largest tumor deposits, percentage of the area of SLN involved by tumor, and tumor penetrative depth (ICC, 0.88, 0.73, 0.68, and 0.83, respectively). There was moderate agreement on the evaluation of subcapsular versus nonsubcapsular location of tumor deposits (ICC = 0.50). Agreement on assessment of extracapsular spread was fair (ICC = 0.39).

CONCLUSIONS

: Assessment of some of the quantitative parameters was highly reproducible between pathologists. However, evaluation of the location of tumor deposits within SLNs and assessment of extracapsular spread was less reproducible. Clearer definitions and training can be expected to improve the reproducibility of assessment. These results have important implications for reliability and reproducibility of these parameters in staging, prediction of outcome, and clinical management of melanoma patients. Cancer 2009. (c) 2009 American Cancer Society.

Comparison of three micromorphometric pathology classifications of melanoma metastases in the sentinel node

OBJECTIVE

The purposes of this study were to determine which classification best predicts additional lymph node disease and survival, and to suggest a threshold below which a completion dissection may be omitted.

SUMMARY BACKGROUND DATA

Three micromorphometric parameters of melanoma sentinel node metastases were compared: invasion depth from the capsule (Starz-classification), maximum diameter (Rotterdam-criteria), and location within the node (Dewar-classification).

METHODS

The pathology slides of 116 patients with tumor-positive sentinel nodes were reviewed. The follow-up data were obtained from the prospectively kept database. The median follow-up duration was 53 months.

RESULTS

Metastases with an invasion depth under 0.3 mm or diameter less than 0.1 mm were not associated with additional involved nodes. Four percent of the patients with metastases with an invasion depth of 0.3 to 1.0 mm had other involved nodes and 3% of the patients with metastases with a diameter of 0.1 to 1.0 mm. Other nodes were involved in 3% of subcapsular metastases, 9% of both subcapsular and parenchymal metastases, and 33% in case of multifocal or extensive disease. The smallest tumor invasion depth and diameter associated with additional involved nodes was 0.4 mm. Only 5-year overall survival in the 3 successive invasion depth categories were statistically significant: 92%, 83%, and 68%. Five-year overall survival was 81% in patients with one involved sentinel node and 60% if there were more.

CONCLUSIONS

Invasion depth and diameter of the metastasis correlate best with the presence of additional nodal disease. Invasion depth best predicts overall survival. It seems justified to refrain from completion dissection in patients with a sentinel node tumor invasion depth up to 0.4 mm.

Photoacoustic Detection of Melanoma Micrometastasis in Sentinel Lymph Nodes

Melanoma is the deadliest form of skin cancer and has the fastest growth rate of all cancer types. Proper staging of melanoma is required for clinical management. One method of staging melanoma is performed by taking a sentinel node biopsy, in which the first node in the lymphatic drainage path of the primary lesion is removed and tested for the presence of melanoma cells. Current standard of care typically involves taking fewer than ten histologic sections of the node out of the hundreds of possible sections available in the tissue. We have developed a photoacoustic method that probes the entire intact node. We acquired a lymph node from a healthy canine subject. We cultured a malignant human melanoma cell line HS 936. Approximately 1×106 cells were separated and injected into the lymph node. We also had a healthy lymph node in which no melanoma cells were implanted. We used a tunable laser system set at 532 nm to irradiate the lymph nodes. Three piezoelectric acoustic detectors were positioned near the lymph node to detect photoacoustic pulses generated within the lymph nodes. We also acquired lymph nodes from pigs and repeated the experiments with increased amplification and improved sensors. We detected photoacoustic responses from a lymph node with as few as 500 melanoma cells injected into the tissue, while normal lymph nodes showed no response. Photoacoustic generation can be used to detect melanoma micrometastasis in sentinel lymph nodes. This detection can be used to guide further histologic study of the node, increasing the accuracy of the sentinel lymph node biopsy.

A comprehensive overview of radioguided surgery using gamma detection probe technology

The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology.

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.

Pathologic examination of sentinel lymph nodes from melanoma patients

In melanoma patients, the sentinel node biopsy (SNB) procedure is a highly accurate staging method, and the tumor-harboring status of the sentinel node (SN) is the most important prognostic factor for patients with early stage disease. For the SN to provide accurate prognostic information, however, it is essential that all "true" SNs are removed and examined diligently. Pathologists should examine multiple hematoxylin-eosin and immunohistochemically stained sections from each SN, but it is unclear from the currently available evidence what is the most appropriate sectioning and staining protocol. Relevant factors to consider include the accuracy of the procedure, the time, labor, and costs involved, and clinical follow-up data which are likely to vary between institutions; hence, individual protocols should be developed locally by pathologists in consultation with their surgical colleagues. At the Sydney Melanoma Unit, four sequential sections of both halves of each SN are examined. The first and fourth sections are stained with hematoxylin-eosin, the second section is stained for S-100 protein, and the third section is stained for HMB-45. Pathologists should not only identify the presence of melanoma metastases within the SN, but also record the size of the largest metastatic focus, tumor penetrative depth (measured from the inner margin of the node capsule to the deepest tumor cell within the SN), and the percentage nodal cross-sectional area involved (as measured on the slides). Potential diagnostic pitfalls in SN evaluation include the misinterpretation of nevus cells, macrophages, or antigen-presenting interdigitating dendritic cells as melanoma. Careful assessment of the morphologic characteristics of the cells and their immunohistochemical profile should prevent misdiagnosis. Routine frozen section examination of SNs from melanoma patients is not recommended. The utility of ultrasound to detect SN metastases (confirmed by fine needle biopsy) is currently being investigated. Whereas potentially this may avoid the need for formal sentinel lymphadenectomy and histopathologic evaluation in some patients, the lack of sensitivity of currently available ultrasound technologies to detect the small micrometastases (<2 mm in diameter), that are typically present in most melanoma patients with a positive SN, limits its current role. In the future, other techniques, such as the use of carbon particles or antimony analysis, may better localize the site of metastases within SNs and permit more focused and efficient pathologic examination of SNs. At present, the role of nonhistopathologic methods of SN evaluation, such as reverse transcription polymerase chain reaction (RT-PCR) and magnetic resonance spectroscopy, remains unclear, and these techniques require further evaluation.

Sentinel lymph node biopsy for melanoma: aspects of pathologic assessment

Sentinel lymph node (SLN) biopsy affords an accurate, minimally invasive means of staging and determining prognosis in patients with melanoma and for identifying those patients who may benefit from complete regional lymph node dissection. Careful and accurate histopathologic assessment of SLNs is critical to achieving optimal reliability of the technique. Micromorphometric parameters of melanoma deposits in SLNs have been shown to be predictive of regional non-SLN involvement and of clinical outcomes. Several non-histopathologic methods of SLN evaluation have been investigated, and while some of them show promise for the future, excision and histopathologic examination currently remains the gold standard for the evaluation of SLNs.

Postoperative morbidity of lymph node excision for cutaneous melanoma-sentinel lymphonodectomy versus complete regional lymph node dissection

For patients with melanoma metastasis to a sentinel lymph node, subsequent complete regional lymph node dissection (CLND) is currently regarded to be the surgical standard. This approach, however, has not been confirmed by controlled studies, so that surgical morbidity is of primary importance. Using clinical examination and a questionnaire, we determined morbidity in 315 patients with axillary or inguinal lymph node excision on whom 275 sentinel lymphonodectomies (SLNEs) and 90 CLNDs were performed. The overall incidence of at least one complication following SLNE was 13.8%. The short-term complication rate was 11.3% (allergic reaction to blue dye 0%, wound breakdown 0%, haematoma 2.5%, wound infection 3.6%, seroma 6.9%). The incidence of long-term complications was 4.1% (persistent tattoo 0.4%, functional deficit 0.4%, nerve dysfunction/pain 0.7% or swelling 2.5%). All complications were mild. Significantly, the complication rate was not higher for patients aged 70 years or older. After CLND, the overall complication rate was significantly higher (65.5%, P<0.000001). The incidence of short-term complications was 50% (haematoma 0%, wound breakdown 6.7%, wound infection 24.7% or seroma 34.8%). The incidence of long-term complications was also 50% (nerve dysfunction/pain 8.9%, functional deficit 16.8%, swelling 37.1%). Overall, inguinal lymph node excision was burdened by a higher complication rate (P=0.015). Age and sex did not influence postoperative morbidity. No deaths linked to either procedure were noted. Complication rates after SLNE are low and most complications are minor and short-lasting. In contrast, CLND has been demonstrated to be a major and potentially morbid surgical procedure. This highlights the importance of testing the therapeutic value that CLND adds to the sentinel lymph node procedure.

The role of hybrid SPECT-CT in oncology: current and emerging clinical applications

Single photon emission computed tomography - computed tomography (SPECT-CT) is an emerging dual-modality imaging technique with many established and potential clinical applications in the field of oncology. To date, there has been a considerable emphasis on the benefits of integrated positron emission tomography - computed tomography (PET-CT) in oncology, but relatively little focus on the clinical utility of SPECT-CT. As with PET-CT, accurate co-registration of anatomical and functional data from a combined SPECT-CT camera often provides complementary diagnostic information. Both sensitivity (superior disease localization) and specificity (exclusion of false-positives due to physiological tracer uptake) are improved, and the functional significance of indeterminate lesions detected on cross-sectional imaging can be defined. This article will review the scope of hybrid SPECT-CT in oncology and illustrate both current and emerging clinical applications.

Radiation exposure to surgical staff during F-18-FDG-guided cancer surgery

PURPOSE

High-energy gamma probes have recently become commercially available, developed for (18)F-FDG probe-guided surgery. The radiation received by the staff in the operating room might limit the use of it, but has never been determined. We therefore wanted to measure the absorbed staff doses at operations where patients had received a preoperative injection of (18)F-FDG.

METHODS

Thirty-four patients with different cancers (breast cancer, melanoma, gastrointestinal cancers, respectively) were operated. At every operation the surgeon was monitored with a TLD tablet on his finger of the operating hand and a TLD tablet on the abdomen. The surgeon and anaesthesiologist were also monitored using electronic dosimeters placed in the trousers lining at 25 operations.

RESULTS

The dose rate to the surgeon's abdominal wall varied between 7.5-13.2 microSv/h, depending on tumour location. The doses to the anaesthesiologists and the finger doses to the surgeon were much lower. About 350-400 MBq, i.e. ca. eight times higher activities than those used in the present study are supposed to be necessary for guiding surgery. It can be calculated from the body doses measured that a surgeon can perform between 150-260 h of surgery without exceeding permissible limits for professional workers.

CONCLUSIONS

The radiation load to the operating staff will generally be so small that it does not present any limitation for FDG-guided surgery. However, it is recommended to monitor the surgical staff considering that the surgeon may be exposed to other radiation sources, and since the staff often includes women of child-bearing age.

Patterns of First-Recurrence and Post-recurrence Survival in Patients with Primary Cutaneous Melanoma After Sentinel Lymph Node Biopsy

BACKGROUND

Sentinel lymph node biopsy (SLNB) has become well accepted in management of patients with primary cutaneous melanoma. An understanding of the pattern of recurrence after SLNB is helpful in coordinating a rational plan of follow-up in these patients. We sought to determine the site and timing of initial recurrence and post-recurrence survival after SLNB.

METHODS

Stage I/II melanoma patients who underwent SLNB during 1991-2004 were identified from a prospective single-institution database. Site and date of first recurrence after SLNB were recorded. Patterns of recurrence after SLNB and post-recurrence survival were analyzed.

RESULTS

One thousand and forty-six patients underwent SLNB. The sentinel lymph node (SLN) was positive in 164 patients (16%). Median follow-up was 36 months for survivors. Median and 3-year relapse-free survival for SLN-positive patients were 41 months and 56%, and for SLN-negative patients were not reached and 87%, respectively (P < .0001). Of the SLN-positive patients, 47% experienced recurrence, compared with 14% SLN-negative patients. The pattern of recurrence stratified by SLN status was similar between the two groups (P = NS). After recurrence, the site of recurrence was the only significant prognostic factor influencing survival (P < .0001).

CONCLUSIONS

Although SLN-positive patients experience recurrence far earlier and more frequently than SLN-negative patients, the pattern of recurrence is similar. After recurrence, its site is the primary determinant of survival.

Intraoperative evaluation of sentinel lymph nodes for metastatic melanoma by imprint cytology

BACKGROUND

Sentinel lymph node biopsy (SLN) has revolutionized nodal staging. Accurate intraoperative evaluation of SLN permits a single procedure, with lymphadenectomy being performed during the initial operative procedure when the SLN is positive. There is a paucity of literature on intraoperative imprint cytology (IIC) evaluation of the SLN in melanoma. The purpose of this article is to present an update to our experience with IIC for SLN in melanoma.

METHODS

Melanoma patients had SLNs examined by IIC. SLNs were bisected, and imprints were made from each half. Imprints were stained with hematoxylin and eosin and with Diff-Quik. Paraffin-embedded sections were examined with multiple hematoxylin and eosin-stained sections from the SLNs in conjunction with immunohistochemical staining for S-100, Melan-A, and HMB-45 proteins.

RESULTS

Metastases were identified in 40 (17%) of 229 patients. Of these, 13 patients were detected by IIC (sensitivity, 33%). The negative predictive value was 88%. No false-positive results were identified (specificity, 100%). The positive predictive value was 100%. The accuracy of IIC was 78%. The sensitivity for detecting macrometastases (>2 mm) was better than that for detecting micrometastases (< or =2 mm): 62% vs. 16% (P < .01). Patients with positive SLNs by IIC had lymphadenectomy under the same anesthetic. A total of 533 nonsentinel lymph nodes were identified in 42 patients. Only two patients (8%) had positive nonsentinel lymph nodes after a negative IIC.

CONCLUSIONS

IIC is a viable alternative to frozen sectioning when intraoperative evaluation is desired. IIC is significantly more sensitive for macrometastases. IIC evaluation of SLNs in melanoma makes a single operative procedure possible for a significant proportion of patients with regional nodal metastases.

Sentinel Node Mapping for Melanoma: Results of Trials and Current Applications

The value of sentinel node (SN) biopsy as a staging procedure and as a guide to prognosis with patients who have melanoma is now clearly established. As well, there is recent clinical trial evidence suggesting a survival benefit for patients found to be SN positive who have an immediate complete lymph node dissection (CLND), compared with those with nodal disease not treated by CLND until it becomes clinically apparent. Clinical trials are ongoing to determine whether CLND is necessary in all patients who are found to be SN positive.

Tumour-induced immune modulation of sentinel lymph nodes

Sentinel lymph nodes (SLNs), being the first nodes to receive lymph from a primary tumour and the preferential site of initial tumour metastases, are intensively exposed to the bioactive products of tumour cells and other associated cells. This makes them ideal for studies of the factors that determine selective tissue susceptibility to metastases. We postulate that tumour-induced immune modulation of SLNs facilitates lymph-node metastases by inhibiting the generation of tumour-specific cytotoxic T cells that are active against tumour cells of primary and metastatic melanomas. Immune modulation of the lymph nodes can be reversed by granulocyte/macrophage colony-stimulating factor (GM-CSF), a finding that has implications for the future therapy of lymph-node metastases.

Survival analysis and clinicopathological factors associated with false-negative sentinel lymph node biopsy findings in patients with cutaneous melanoma

BACKGROUND

We analyzed the outcomes and factors associated with false-negative (FN) results of sentinel lymph node (SLN) biopsy findings in patients with cutaneous melanoma. SLN biopsy failure rate was defined as nodal recurrence in the biopsied regional basin without previous local or in-transit recurrence.

METHODS

Between April 1997 and December 2004, a total of 1207 patients with cutaneous melanoma with a median Breslow thickness of 2.4 mm underwent SLN biopsy by preoperative and intraoperative lymphoscintigraphy combined with dye injection. In 228 cases, we found positive SLNs; of these, 220 underwent completion lymph node dissection (CLND). Median follow-up was 3 years.

RESULTS

The SLN biopsy failure rate was 5.8% (57 of 979 SLN negative). Median time to occurrence of FN relapse after SLN biopsy was 16 months (range, 3-74 months). The FN SLN biopsy results correlated with primary tumor thickness >4 mm (P = .0012), primary tumor ulceration (P = .0002), primary tumor level of invasion Clark stage IV/V (P = .0005), and nodular melanoma histological type (P = .0375). Five-year overall survival, calculated from the date of primary tumor excision, in the FN group was 53.7%, which was not statistically significantly worse than the CLND group (56.8%; P = .9). The FN group was characterized by a higher ratio of two or more metastatic nodes and extracapsular involvement of lymph nodes after LND compared with the CLND group (P < .0001 and P < .0001, respectively). Additional detailed pathological review of FN SLN revealed metastatic disease in 14 patients, which decreased the SLN biopsy failure rate to 4.4% (43 of 979).

CONCLUSIONS

Survival of patients with FN results of SLN biopsy does not differ statistically significantly from that of patients undergoing CLND, although it is slightly lower. The SLN biopsy failure rate is approximately 5.0% in long-term follow-up and is associated mainly with the same factors that indicate a poor prognosis in primary melanoma.

Experimental frontiers for clinical applications: Novel approaches to understanding mechanisms of lymph Node metastases in melanoma

Sentinel lymph nodes are the first nodes to receive lymph from primary tumors and are the preferential site of initial metastases. Sentinel nodes show morphology changes that suggests immune modulation with reduced antigen-presenting dendritic cells, activated T lymphocytes, high endothelial venules and transvenular migration of T lymphocytes. Tumor cells generate down-regulatory molecules. We postulate that tumor-induced immune dysfunction facilitates establishment of nodal metastases. Nodal immune modulation can be reversed by granulocyte macrophage colony-stimulating factor (GMCSF), a finding with implications for future therapy to prevent or reverse these nodal metastases.

Surgical Management of Primary Cutaneous Melanoma: Excision Margins and the Role of Sentinel Lymph Node Examination

Surgical strategies for managing patients who have primary cutaneous melanoma have changed dramatically over the past 30 years. More conservative excision margins have been shown to be adequate, and routine complete lymph node dissection (CLND)has been abandoned since the sentinel node (SN) biopsy technique was introduced. Knowledge of a patient's SN status not only provides a reliable guide to prognosis, but also allows CLND to be avoided in 80% to 85% of patients. Recent clinical trial results suggest that SN biopsy, with immediate CLND if an SN is positive,confers a survival advantage in those who have metastatic disease in regional nodes. Minimally invasive and noninvasive methods of SN assessment, such as magnetic resonance spectroscopy, are being evaluated.