Estudio comparativo entre el método One step nucleic acid amplification y el método convencional en la estadificación en cáncer de mama: un aumento en la detección de micrometástasis / Comparative study of the One step nucleic acid amplification method and the conventional method in axillary staging in breast cancer: an increase in the detection of micrometastases

Objetivos. El método One step nucleic acid amplification (OSNA) se ha incorporado para el estudio del ganglio centinela (GC) en cáncer de mama como alternativa al estudio convencional histológico (MC). El propósito de nuestro estudio fue comparar la estadificación por ganglio centinela (EGC) obtenida por el método OSNA con la obtenida mediante MC. Material y métodos. Se seleccionaron pacientes con cáncer de mama y EGC recogidas durante los años 2009-2010 y 2012-2013, estudiadas con MC y método OSNA. Se analizaron diferentes parámetros clínico-patológicos. Resultados. Se incluyó a 1.124 pacientes, 590 estudiadas por MC y 534 por método OSNA. La EGC inicial fue: pN0: MC 349 (59,2%) y OSNA 335 (62,7%); pN0(i+): MC 74 (12,5%) y OSNA 14 (2,6%); pN1mi: MC 59 (10%) y OSNA 77 (14,4%); pN1: MC 108 (18,3%) y OSNA 108 (20,3%). Se encontraron diferencias estadísticamente significativas entre la EGC por método OSNA y MC (p<0,001), a expensas de las tasas de pN1mi y pN0(i+). Se seleccionó a 224 pacientes con EGC pN1mi y pN0(i+) para determinar si las diferencias encontradas podrían atribuirse a distintas características clínico-patológicas. El método OSNA detecta el doble de micrometástasis (84,6%). Conclusiones. En nuestra casuística, por el método OSNA se observa un incremento significativo de pN1mi (84,6% vs. 44,4%) y una disminución de pN0(i+) respecto al estudio convencional, diferencias que no están condicionadas por los parámetros clínico-patológicos. El 75% de casos con pN1mi por OSNA muestra un número de copias inferior a 1.000 (AU)

Objetives. The One Step Nucleic Acid Amplification (OSNA) method has been incorporated in the study of the sentinel lymph node (SLN) in breast cancer as an alternative to conventional histological study. The aim of our study was to compare sentinel lymph node staging (SLNS) obtained by the OSNA method with that obtained by the conventional method (CM). Material and methods. We identified patients with breast cancer and SLN study during the periods 2009-2010 and 2012-2013, who underwent the CM and by OSNA. We analysed different clinicopathological parameters. Results. A total of 1124 patients were studied, 590 by CM and 534 by OSNA. SLNS was: pN0: CM 349 (59.2%) and OSNA 335 (62.7%); pN0(i+): CM 74 (12.5%) and OSNA 14 (2.6%); pN1mi: CM 59 (10%) and OSNA 77 (14.4%); pN1: CM 108 (18.3%) and OSNA 108 (20.3%). Statistically significant differences were found between the SLNS by OSNA and CM (p <0.001), due to the rates of pN1mi and pN0(i+). To determine whether this statistical significance could be attributed to different clinicopathological features, 224 patients were selected from the initial series with SLN pN1mi and pN0(i+). In this subgroup, the OSNA method detected twice as many micrometastases (pN1mi) (84.6%). Conclusions. In our series, the OSNA method resulted in a significant increase in pN1mi (84.6% vs 44.4%) and a decrease in pN0(i+) compared with the conventional method. Those differences were not affected by clinicopathological parameters. Most cases (75%) with pN1mi by OSNA showed less than 1000 copies (AU)

Evaluación del coste económico de la técnica de la biopsia selectiva del ganglio centinela en melanoma / Cost Analysis of Sentinel Lymph Node Biopsy in Melanoma

INTRODUCCIÓN Y OBJETIVO: La técnica de la biopsia selectiva del ganglio centinela (BSGC) es la mejor herramienta para la estadificación ganglionar en el melanoma, permitiendo la realización de una linfadenectomía selectiva, es decir, reservada solo a aquellos pacientes que muestran el GC positivo para metástasis. Nuestro objetivo fue evaluar el coste económico de la técnica de la BSGC, ya que se ha convertido en el procedimiento recomendado como estándar en la atención al paciente con melanoma, y es necesaria para la inclusión de los pacientes en los ensayos clínicos. Existe además escasa bibliografía en nuestro medio sobre su relevancia económica. MÉTODO: De forma prospectiva se recogieron 100 pacientes a los que se realizó la técnica entre los años 2007-2010 con un procesamiento histológico transhiliar bivalvo multisecciones. Realizamos un cálculo aproximado del precio de la técnica utilizando las tarifas de precios oficiales de la Región de Murcia. RESULTADOS: El porcentaje de positividad de nuestra serie fue del 20%, con un número medio de ganglios de 1,96 y un 44% de melanomas delgados. El precio total de la técnica es de 9.486,57- 10.471,29 euros, siendo una parte muy importante de la misma atribuible al procesamiento histopatológico (5.769,36 euros). DISCUSIÓN: La técnica de la BSGC tiene un precio muy considerable, aunque en consonancia con otras referencias americanas previamente descritas. La optimización de la técnica vendrá dada en función de la selección cada vez más adecuada de los pacientes que deben someterse a ella, y a la estandarización de un modelo histopatológico sensible en la detección, pero a la vez sencillo en el procesamiento

INTRODUCTION AND OBJECTIVE: Sentinel lymph node biopsy (SLNB) is the most useful tool for node staging in melanoma. SLNB facilitates selective dissection of lymph nodes, that is, the performance of lymphadenectomy only in patients with sentinel nodes positive for metastasis. Our aim was to assess the cost of SLNB, given that this procedure has become the standard of care for patients with melanoma and must be performed whenever patients are to be enrolled in clinical trials. Furthermore, the literature on the economic impact of SLNB in Spain is scarce. METHOD: From 2007 to 2010, we prospectively collected data for 100 patients undergoing SLNB followed by transhilar bivalving and multiple-level sectioning of the node for histology. Our estimation of the cost of the technique was based on official pricing and fee schedules for the Spanish region of Murcia. RESULTS: The rate of node-positive cases in our series was 20%, and the mean number of nodes biopsied was 1.96; 44% of the patients in the series had thin melanomas. The total cost was estimated at between D 9486.57 and D 10 471.29. Histopathology accounted for a considerable portion of the cost (D 5769.36). DISCUSSION: The cost of SLNB is high, consistent with amounts described for a US setting. Optimaluse of SLNB will come with the increasingly appropriate selection of patients who should undergo the procedure and the standardization of a protocol for histopathologic evaluation that is both sensitive and easy to perform

Scoping it out: A change in sentinel lymph node surgery coding practice.

Recently, a committee of clinicians noted that registry data regarding the Scope of Regional Lymph Node Surgery did not match the expected standards of clinical practice. Review of data from their own registries led them to the conclusion that much of the problem lay not in clinical practice or in registry coding, but in the coding instructions themselves. In particular, the existing instructions for this surgery did not make clear that coding should be based on the operative report rather than the pathology report. As a result, the instructions failed to give adequate guidance for distinguishing sentinel lymph node biopsies from regional lymph node dissections where multiple nodes were removed. In addition, somewhat separately from these issues, the problem of coding multiple surgeries to show the cumulative effect of the surgery contributed to the miscoding of Scope of Regional Lymph Node Surgery. This article describes the Commission on Cancer's (CoC) exploration of the problem through a field test, and provides background for the changes in coding instructions introduced for use beginning with cases diagnosed in 2012.

Melanoma staging and sentinel lymph node biopsy.

Tumor staging of melanoma is a crucial step for estimating patient prognosis, deciding on therapy approach, and efficient collection, analysis, comparison and communication of scientific data across borders and research groups. Recently, the Melanoma Staging Committee of the American Joint Committee on Cancer (AJCC) has proposed a revision of the widely used melanoma staging system, using an evidence-based approach, to reflect the improved understanding of this disease. Important adjustments were made related to the role of mitotic rate as a prognostic factor, definition of N category and classification of all microscopic nodal metastases, regardless of the extent of tumor burden, and specifically including micrometastases detected by immunohistochemistry as stage III. These revisions are to be implemented by early 2010 and are likely to be adopted and incorporated in international guidelines. Within the updated AJCC staging system, sentinel lymph node biopsy (SLNB) remains a standard-of-care diagnostic procedure, widely accepted as an important prognostic tool. According to current recommendations, SLNB is routinely offered as a staging procedure in patients with tumors more than 1 mm in thickness. Beyond its prognostic value, the therapeutic benefit of this procedure in improving overall survival yet remains to be proven. This article reviews and discusses the new aspects and challenges of the current staging recommendations for melanoma.

Sentinel node tumor burden according to the Rotterdam criteria is the most important prognostic factor for survival in melanoma patients: a multicenter study in 388 patients with positive sentinel nodes.

SUMMARY BACKGROUND DATA: The more intensive sentinel node (SN) pathologic workup, the higher the SN-positivity rate. This is characterized by an increased detection of cases with minimal tumor burden (SUB-micrometastasis <0.1 mm), which represents different biology. METHODS: The slides of positive SN from 3 major centers within the European Organization of Research and Treatment of Cancer (EORTC) Melanoma Group were reviewed and classified according to the Rotterdam Classification of SN Tumor Burden (<0.1 mm; 0.1-1 mm; >1 mm) maximum diameter of the largest metastasis. The predictive value for additional nodal metastases in the completion lymph node dissection (CLND) and disease outcome as disease-free survival (DFS) and overall survival (OS) was calculated. RESULTS: In 388 SN positive patients, with primary melanoma, median Breslow thickness was 4.00 mm; ulceration was present in 56%. Forty patients (10%) had metastases <0.1 mm. Additional nodal positivity was found in only 1 of 40 patients (3%). At a mean follow-up of 41 months, estimated OS at 5 years was 91% for metastasis <0.1 mm, 61% for 0.1 to 1.0 mm, and 51% for >1.0 mm (P < 0.001). SN tumor burden increased significantly with tumor thickness. When the cut-off value for SUB-micrometastases was taken at <0.2 mm (such as in breast cancer), the survival was 89%, and 10% had additional non-SN nodal positivity. CONCLUSION: This large multicenter dataset establishes that patients with SUB-micrometastases <0.1 mm have the same prognosis as SN negative patients and can be spared a CLND. A <0.2 mm cut-off for SUB-micrometastases does not seem correct for melanoma, as 10% additional nodal positivity is found.

Minimal metastatic disease in sentinel lymph nodes in breast carcinoma: some modest proposals to refine criteria for "isolated tumor cells".

Axillary lymph node status is one of the most important prognostic factors in breast carcinoma. The weight of cumulative evidence suggests that the development of the sentinel lymph node (SLN) biopsy procedure has not only allowed for accurate lymph node-staging but has also helped avoid the morbidity of a full axillary dissection in those patients who are unlikely to have metastatic tumor in that location. The detection of metastases in SLNs is facilitated by the, now relatively routine, enhanced histopathologic examination via step-sectioning and immunohistochemistry. In clinical terms, the finding of a metastatic deposit that measures between 0.2 and 2 mm, that is, "micrometastasis" in a SLN is largely noncontroversial; however, the presence of smaller metastatic foci detected either by routine hematoxylin and eosin stain or by cytokeratin immunostain [<0.2 mm, ie, so-called "isolated tumor cells (ITCs)"] has remained problematic since the advent of the SLN biopsy. In this communication, attention is drawn to the broad morphologic range of metastatic disease in SLN that may be placed in the category of so-called ITC. To facilitate the reproducible classification of the various strata of minimal metastasis in sentinel lymph nodes, we recommend the following: (1) the term "isolated tumor cell" (note singular form) be restricted to cases that show the presence of only a single tumor cell. (2) In situations where there are multiple isolated single cells and/or cell cluster(s) present and each cluster measures<0.2 mm, the term "submicroscopic metastasis" be adopted and an actual count of tumor cells present may be given. (3) Restrict the use of the term micrometastasis to cases wherein the largest metastatic focus is larger than 0.2 mm but smaller than 2.0 mm.

TNM: evolution and relation to other prognostic factors.

The TNM Classification describes the anatomic extent of cancer. TNM's ability to separately classify the individual tumor (T), node (N), and metastasis (M) elements and then group them into stages differs from other cancer staging classifications (e.g., Dukes), which are only concerned with summarized groups. The objectives of the TNM Classification are to aid the clinician in the planning of treatment, give some indication of prognosis, assist in the evaluation of the results of treatment, and facilitate the exchange of information. During the past 50 years, the TNM system has evolved under the influence of advances in diagnosis and treatment. Radiographic imaging (e.g., endoscopic ultrasound for the depth of invasion of esophageal and rectal tumors) has improved the accuracy of the clinical T, N, and M classifications. Advances in treatment have necessitated more detail in some T4 categories. Developments in multimodality therapy have increased the importance of the "y" symbol and the R (residual tumor) classification. New surgical techniques have resulted in the elaboration of the sentinel node (sn) symbol. The use of immunohistochemistry has resulted in the classification of isolated tumor cells and their distinction from micrometastasis. The most important challenge facing users of the TNM Classification is how it should interface with the large number of non-anatomic prognostic factors that are currently in use or under study. As non-anatomic prognostic factors become widely used, the TNM system provides an inviting foundation upon which to build a prognostic classification; however, this carries a risk that the system will be overwhelmed by a variety of prognostic data. An anatomic extent-of-disease classification is needed to aid practitioners in selecting the initial therapeutic approach, stratifying patients for therapeutic studies, evaluating non-anatomic prognostic factors at specific anatomic stages, comparing the weight of non-anatomic factors with extent of disease, and communicating the extent of disease data in a uniform manner. Methods are needed to express the overall prognosis without losing the vital anatomic content of TNM. These methods should be able to integrate multiple prognostic factors, including TNM, while permitting the TNM system to remain intact and distinct. This article discusses examples of such approaches.

TNM, sixth edition: new developments in general concepts and rules.

This article describes changes and clarifications in the 6th edition of TNM that concern site-independent rules, regarding such aspects as sentinel lymph node biopsy, methods to distinguish between micrometastasis and isolated tumor cells, classification of tumors undergoing treatment, tumor deposits in lymph drainage beds, the number of lymph nodes needed for pathologic classification, and classification of residual tumor. These changes mainly reflect advances in diagnosis and treatment, and modulate rather than change the basic rules of classification.

New TNM staging criteria for head and neck tumors.

Cancers of the head and neck have always represented a unique perspective in cancer staging. Not only are these lesions numerous in terms of anatomic sites of origin, but, unlike most other major cancers, they frequently and readily lend themselves to adequate clinical assessment by visual inspection and palpation, which greatly facilitates documentation by the trained clinician. In addition, their location often involves treatment programs that focus on nonsurgical organ-preservation strategies, and thus anatomic and histological data for comprehensive pathologic staging are often not available. Nevertheless, the processes involved in surgical decision-making and radiotherapy treatment planning require meticulous assessment and documentation of the extent of locoregional disease. For all these reasons it is especially important to perform reliable and accurate pretreatment clinical staging of head and neck cancers. Also, many patients who succumb to head and neck cancer do so as a result of locoregional disease. Therefore, the staging system must take into account detailed local anatomic features that dictate management, since the degree of involvement of these structures by tumor may be as important as distant metastasis in threatening survival. For this reason the most recent cancer staging classification (6th edition) of the International Union Against Cancer (UICC) and the American Joint Committee on Cancer (AJCC) includes new criteria for the more advanced cases (e.g., T4 categories and stage IV disease). These criteria reflect the fact that in heterogeneous populations there is a realistic opportunity for cure in some patients but not in others. This review summarizes the criteria used in the new TNM for head and neck tumors, and outlines the rationale behind the current changes. It also provides some guidance regarding optimal source data to facilitate classification in the registry setting. In addition, the need for additional changes in the future is recognized.

New TNM melanoma staging system: linking biology and natural history to clinical outcomes.

The American Joint Committee on Cancer (AJCC) implemented major revisions of the melanoma TNM and stage grouping criteria in the recently published 6th edition of the Staging Manual. The new staging system better reflects independent prognostic factors that are used in clinical trials and in reporting the outcomes of various melanoma treatment modalities. Major revisions include: 1) melanoma thickness and ulceration but not level of invasion to be used in the T classification, 2) the number of metastatic lymph nodes rather than their gross dimensions and the delineation of microscopic vs. macroscopic nodal metastases to be used in the N classification, 3) the site of distant metastases and the presence of elevated serum lactic dehydrogenase (LDH) to be used in the M classification, 4) an upstaging of all patients with Stage I, II, and III disease when a primary melanoma is ulcerated, 5) a merging of satellite metastases around a primary melanoma and in transit metastases into a single staging entity that is grouped into Stage III disease, and 6) a new convention for defining clinical and pathological staging so as to take into account the new staging information gained from intraoperative lymphatic mapping and sentinel node biopsy.

The role of sentinel lymph node biopsy for melanoma.

Regional lymph nodes are a common site of melanoma metastases, and the presence or absence of melanoma in regional lymph nodes is the single most important prognostic factor for predicting survival. Furthermore, identification of metastatic melanoma in lymph nodes and excision of these nodes may enhance survival in a subgroup of patients whose melanoma has metastasized only to their regional lymph nodes and not to distant sites. Sentinel lymph node (SLN) biopsy was developed as a low morbidity technique to stage the lymphatic basin without the potential morbidity of lymphedema and nerve injury. The presence or absence of metastatic melanoma in the SLN accurately predicts the presence or absence of metastatic melanoma in that lymph node basin. When performed by experienced centers, the false-negative rate of SLN biopsy is very low. As such, the nodal basin that contains a negative SLN will usually be free of microscopic disease. Since occult micrometastatic disease affects only 12% to 15% of patients with melanoma, selective SLN dissection allows up to 85% of patients with melanoma to be spared a formal lymph node dissection, thus avoiding the complications usually associated with that procedure. While standard pathologic evaluation of lymph nodes may miss metastatic melanoma cells, more sensitive techniques are developing which may identify micrometastases more accurately. The clinical significance of these micrometastases remains unknown and is the subject of active investigations.