Pre-treatment surgical para-aortic lymph node assessment in locally advanced cervical cancer

 

Abstract

Background

Cervical cancer is the most common cause of death from gynaecological cancers worldwide. Locally advanced cervical cancer, FIGO stage equal or more than IB1 is treated with chemotherapy and external beam radiotherapy followed by brachytherapy. If there is metastatic para-aortic nodal disease radiotherapy is extended to additionally cover this area. Due to increased morbidity, ideally extended-field radiotherapy is given only when para-aortic nodal disease is proven. Therefore accurate assessment of the extent of the disease is very important for planning the most appropriate treatment.

Objectives

To evaluate the effectiveness and safety of pre- treatment surgical para-aortic lymph node assessment for woman with locally advanced cervical cancer (FIGO stage IB2 to IVA).

Search methods

We searched the Cochrane Gynaecological Cancer Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1), MEDLINE and EMBASE (up to January 2011). We also searched registers of clinical trials, abstracts of scientific meetings, reference lists of included studies and contacted experts in the field.

Selection criteria

Randomised controlled trials (RCTs) that compared surgical para-aortic lymph node assessment and dissection with radiological staging techniques, in adult women diagnosed with locally advanced cervical cancer.

Data collection and analysis

Two reviewers independently assessed whether potentially relevant trials met the inclusion criteria, abstracted data and assessed risk of bias. One RCT was identified so no meta-analyses were performed.

Main results

We found only one trial, which included 61 women, that met our inclusion criteria. This trial reported data on surgical versus clinical staging and an assessment of the two surgical staging techniques; laparoscopic (LAP) versus extraperitoneal (EXP) surgical staging. The clinical staging was either a contrast-enhanced CT scan or MRI scan of the abdomen and pelvis to determine nodal status.

In this trial, clinical staging appeared to significantly prolong overall and progression-free survival compared to surgical staging. There was no statistically significant difference in the number of women who experienced severe (grade 3 or 4) toxicity.

There was no statistically significant difference in the risk of death, disease recurrence or progression, blood loss, severe toxicity and the duration of the operational procedure between LAP and EXP surgical staging techniques.

The strength of the evidence is weak in this review as it is based on one small trial which was at moderate risk of bias.

Authors' conclusions

From the one available RCT we found insufficient evidence that pre-treatment surgical para-aortic lymph node assessment for locally advanced cervical cancer is beneficial, and it may actually have an adverse effect on survival. However this conclusion is based on analysis of a small single trial and therefore definitive guidance or recommendations for clinical practice cannot be made.

Therefore the decision to offer surgical pre-treatment assessment of para-aortic lymph nodes in locally advanced cervical cancer needs to be individualised. The uncertainty regarding any impact on survival from pre-treatment para-aortic lymph node assessment should be discussed openly with the women.

 

Plain language summary

The role of surgical assessment of lymph nodes before treatment for women with locally advanced cervical cancer

Cervical cancer arises from the neck of the womb (cervix). Cervical screening programmes have decreased the rate of advanced cervical cancer. However, a significant number of cases still present with locally advanced disease that involves large cervical tumours ( > 4cm) or tumours that extend to the upper vagina. The larger the primary tumour, the greater the likelihood of metastasis (spread of cancer to other areas of the body). Cervical cancer spreads to the lymph nodes in the pelvis and around the aorta (one of the major blood vessels in the abdomen). Stage is a standardised assessment of the size of the cancer and if it has spread to adjacent or distant sites. Stage for stage, women with para-aortic lymph node metastases at presentation have a lower survival than those who do not have para-aortic metastases at presentation.

Accurate detection of involved para-aortic lymph nodes helps to tailor radiotherapy so that it includes this area (extended field radiotherapy). It also provides prognostic information. Different methods have been used to detect para-aortic lymph node metastases including surgical and radiological (various types of x-rays) techniques, however it is unclear which is more accurate.

The purpose of this review was to assess the available literature on the effectiveness and safety of pre-treatment surgical para-aortic lymph node assessment for locally advanced cervical cancer. We found only one randomised controlled trial (RCT) that assessed non-surgical staging versus surgical staging. We found limited evidence that suggested that clinical staging may offer a survival benefit (in terms of overall and progression-free survival) compared with surgical staging, but the strength of the evidence from this small trial is weak and the trial was at moderate risk of bias. There was no statistically significant difference in any of the reported outcomes between two surgical staging techniques examined in the trial.

Due to the small number of patients with locally advanced cervical cancer in only one included trial there was insufficient evidence to conclude that any of the staging techniques are superior to each other. This review highlights the need for future good quality, well designed trials which report not only survival and severe adverse event outcomes but also examine quality of life (QoL) outcome data.

 

Resumen

Antecedentes

Evaluación quirúrgica pretratamiento de ganglios linfáticos paraaórticos en el cáncer de cuello de útero localmente avanzado

El cáncer de cuello de útero es la causa más frecuente de muerte por cáncer ginecológico en todo el mundo. El cáncer de cuello de útero localmente avanzado, en estadio FIGO igual o mayor que IB1, se trata con quimioterapia y radioterapia de haz externo seguida de braquiterapia. Si hay metástasis en los ganglios linfáticos paraaórticos, la radioterapia se extiende para cubrir además esta área. Debido al aumento de la morbilidad, idealmente la radioterapia de campo extendido se administra sólo cuando el compromiso de los ganglios paraaórticos está comprobado. Por consiguiente, la evaluación exacta de la extensión de la enfermedad es muy importante para planificar el tratamiento más apropiado.

Objetivos

Evaluar la efectividad y seguridad de la evaluación quirúrgica pretratamiento de ganglios linfáticos paraaórticos en mujeres con cáncer de cuello de útero localmente avanzado (estadio FIGO IB2 a IVA).

Estrategia de búsqueda

Se realizaron búsquedas en el Registro de Ensayos del Grupo Cochrane de Cáncer Ginecológico (Cochrane Gynaecological Cancer Group) Registro Cochrane Central de Ensayos Controlados (Cochrane Central Register of Controlled Trials) (CENTRAL) (The Cochrane Library 2011, número 1), MEDLINE y EMBASE (hasta enero 2011). También se buscó en los registros de ensayos clínicos, los resúmenes de reuniones científicas, las listas de referencias de los estudios incluidos y se estableció contacto con expertos en el campo.

Criterios de selección

Ensayos controlados aleatorios (ECA) que compararon la evaluación quirúrgica y disección de ganglios linfáticos paraaórticos con las técnicas de estadiaje radiológicas, en mujeres adultas con diagnóstico de cáncer de cuello de útero localmente avanzado.

Obtención y análisis de los datos

Dos revisores evaluaron de forma independiente si los ensayos potencialmente pertinentes cumplían los criterios de inclusión, extrajeron los datos y evaluaron el riesgo de sesgo. Se identificó un ECA, de manera que no se realizaron metanálisis.

Resultados principales

Sólo se encontró un ensayo con 61 mujeres que cumplió los criterios de inclusión. Este ensayo presentó datos sobre estadiaje quirúrgico versus clínico y una evaluación de las dos técnicas de estadiaje quirúrgico; estadiaje quirúrgico laparoscópico (LAP) versus extraperitoneal (EXP). El estadiaje clínico era ya sea una tomografía computarizada con contraste o una resonancia magnética del abdomen y la pelvis para determinar el estado ganglionar.

En este ensayo, al parecer el estadiaje clínico prolongó de forma significativa la supervivencia general y la supervivencia sin progresión en comparación con el estadiaje quirúrgico. No hubo diferencias estadísticamente significativas en cuanto al número de pacientes que presentaron toxicidad grave (de grado 3 ó 4).

No hubo diferencias estadísticamente significativas en el riesgo de muerte, recidiva o progresión de la enfermedad, pérdida de sangre, toxicidad grave y duración del procedimiento quirúrgico entre las técnicas de estadiaje quirúrgico LAP y EXP.

La fuerza de las pruebas de esta revisión es débil, ya que se basa en un ensayo con bajo número de participantes que tenía un riesgo de sesgo moderado.

Conclusiones de los autores

A partir del único ECA disponible, se encontraron pruebas insuficientes de que la evaluación quirúrgica pretratamiento de ganglios linfáticos paraaórticos para el cáncer de cuello de útero localmente avanzado es beneficiosa, y en realidad puede tener un efecto adverso sobre la supervivencia. Sin embargo, esta conclusión se basa en el análisis de un único ensayo con bajo número de participantes y, por lo tanto, no puede brindarse orientación o recomendaciones definitivas para la práctica clínica.

En consecuencia, la decisión de ofrecer evaluación quirúrgica pretratamiento de los ganglios linfáticos paraaórticos en el cáncer de cuello de útero localmente avanzado debe ser individualizada. La incertidumbre con respecto a cualquier repercusión sobre la supervivencia de la evaluación de ganglios linfáticos paraaórticos pretratamiento debe tratarse abiertamente con las pacientes.

Traducción

Traducción realizada por el Centro Cochrane Iberoamericano