Management of cervical cancer patients with isolated para-aortic lymph node metastases.

To the editor: For patients with locally advanced cervical cancer, the current guidelines recommend primary chemoradiation [1]. Therefore, pretherapeutic staging has an important role in the management of female patients with locally advanced cervical cancer. Assessment of the nodal involvement of the para-aortic lymph node (PALN) is critical for determining the field of radiation therapy (RT). Extended-field RT, concurrent cisplatin-containing chemotherapy, and brachytherapy should be considered in the case of PALN metastasis.

Jang et al. [2] report the outcomes of 40 cervical cancer patients with isolated PALN metastases at initial diagnosis. This interesting and valuable article demonstrates the association between treatment outcomes and the features of PALN metastasessuch as size, site, and number. The number and size of PALNs were shown to correlate with progression-free survival. The authors suggest that the radiologic features of PALN can be used to determine the prognosis of patients with isolated PALN metastases.

As the authors define PALN involvement based on imaging, the criteria for lymph node involvement should be clarified. In addition, it should also be noted that there are limitations including the false-positive and false-negative results of conventional imaging studies (magnetic resonance imaging or computed tomography) in detecting PALN metastases. It makes hard for clinicians to determine whether to perform extended-field RT based solely on imaging studies. It would be even more interesting if the authors were to show the correlation between the radiologic and pathologic findings in seven patients who underwent radical hysterectomy. In recent years, positron emission tomography/computed tomography (PET/CT) has been recommended for stage IB2 or advanced disease as it is considered to be more sensitive than conventional imaging studies in detecting node or distant metastases [3]. Future studies based on PET/CT are required in order to identify prognostic factors and treatment outcomes for locally advanced cervical cancer.

Furthermore, survival data for patients with PALN metastases detected surgically and treated by extended-field RT in a randomized trial setting is rare [4]. Therefore, the impact of surgical staging in women with locally advanced cervical cancer should be evaluated in future trials, considering the high rate of false-negative PALN involvement from imaging studies. Bearing in mind that postoperative complications and the delay of definite chemoradiation can occur from nodal staging surgery, a comprehensive cost-effective analysis is required to clarify the best treatment strategy for locally advanced stage cervical cancer.

Reply to JY Lee

We would like to thank Dr. Lee for interest and comments regarding "Prognostic factors and treatment outcome after radiotherapy in cervical cancer patients with isolated para-aortic lymph node metastases."

The purpose of the present study was to evaluate the association between treatment outcomes and the radiologic features of metastatic para-aortic lymph node (PALN) in cervix cancer [1]. As you mentioned, our study has some limitations due to only radiologic evaluations (computed tomography [CT] and magnetic resonance imaging [MRI]) of enlarged PALN (size greater than 1 cm) in most patients except 7 patients who underwent radical surgery and had biopsy proven PALN metastases and 2 with positive uptake on positron emission tomography (PET). To have enough follow-up periods, we included patients between 1994 and 2009. But only after year 2008, PET scan has been a routine study for locally advanced cervical cancer.

Selman et al. [2] pooled a total of 5,042 patients for meta-analysis on diagnostic accuracy of tests for lymph node status in primary cervical cancer. And they found high specificity of 97.6%, 93.2%, and 92.3% with relatively low sensitivity of 74.7%, 55.5%, and 57.5% on PET, MRI, and CT, respectively. Considering unsatisfactory sensitivity of imaging with CT and MRI and heterogeneous group of patients, 3 year overall survival rate of 44% is similar to the previous reports. Among 7 patients who underwent radical surgery and were found to have microscopic PALN metastases only, 4 patients were long-term survivors and the other 3 died within 3 years. Gold analyzed data from Gynecologic Oncology Group (GOG) 120 and GOG 165 showed women with stage III and IV disease in the surgical group had better progression free survival and overall survival compared with those in the radiological group even though selection bias was a problem [3].

With advanced imaging and surgical technology and to avoid overtreatment with increased complication from extended radiation field or undertreatment, accurate evaluation of PALN metastases including positron emission tomography/computed tomography is important and has been an essential study in most cancer center. Brockbank et al. [4] thoroughly reviewed pretreatment surgical PALN assessment in locally advanced cervical cancer. They summarized that non-randomized controlled trial published data, and suggests that surgical staging is more accurate than available imaging modalities with proven safety, and also complete debulking of involved para-aortic nodes appears to translate into a survival advantage. As Brockbank et al. [4] suggested, the decision to offer surgical pretreatment assessment of PALN needs to be individualized.