Sentinel node identification in cervical cancer patients undergoing transperitoneal radical hysterectomy: a study of 100 cases

Lymphatic mapping and sentinel lymph node detection in women with cervical cancer

Lymphatic mapping and sentinel node detection have been applied to almost every solid tumor and sentinel node status have become part of the American Joint Commission on Cancer (AJCC) staging criteria in both breast cancer and malignant melanoma. As the presence of metastatic disease in lymph nodes is the most important prognostic factor on survival in women with cervical cancer, the ability to reliably detect sentinel nodes might triage women to adjuvant radiotherapy without the need for full lymphadenectomies and their associated morbidity. To date, multiple international investigators have performed single institution investigations with promising results. Overall, 831 women have been undergoing lymphatic mapping and sentinel node detection as part of their cervical cancer therapy as reported in the literature. Combining results from all these studies, a sentinel node was identified in 90% of cases with an overall sensitivity of detecting metastatic disease of 92% with an 8% false negative rate. The overall negative predictive value was over 97%. There remain controversies in moving forward with accepting sentinel node biopsy as the standard in treating women cervical cancer including 1) determining an acceptable false-negative rate, 2) establishing the importance of micrometastatic disease or isolated tumor cells in sentinel nodes, and 3) discovering the minimum number of cases a surgeon needs to become proficient in mapping techniques. Large, multi-institutional studies in both Europe and the United States are nearing completion and their results should help guide the future direction for sentinel node technologies in the treatment of cervical cancer.

Advances in Surgical Treatment of Cervical Cancer

Radical hysterectomy has been the standard surgical treatment for cervical cancer, achieving a good survival outcome. However, it is a major operation that has considerable potential long-term morbidity. With good prognosis achieved in most early cervical cancers, there is a trend towards more emphasis on maintaining good quality of life post-treatment. Many women diagnosed with cervical cancer are young, and fertility-sparing surgery such as trachelectomy would preserve their reproductive potential. Minimally invasive surgery, such as laparoscopic radical hysterectomy, can potentially improve post-operative recovery and cosmetic results while maintaining oncological safety. Sentinel lymph nodes assessment can minimize unnecessary systematic pelvic lymphadenectomy. Radicality of the hysterectomy may also be reduced in selected individuals with good prognostic factors, thus minimizing long-term pelvic floor dysfunction. This review aims to give a broad overview of the current status of these new trends in surgical management for cervical cancer.

Where to look for the sentinel lymph node in cervical cancer

OBJECTIVE

The aim of this study was to analyze lymphatic spread to pelvic, parametrial, and paraaortic lymph nodes in patients with cervical cancer.

STUDY DESIGN

We reviewed 619 patients with invasive cervical cancer treated by radical abdominal hysterectomy and systematic pelvic or pelvic and paraaortic lymphadenectomy between 1971 and 2005. The present study included 61 patients with one positive lymph node (10%) and 59 patients with two positive lymph nodes (10%) at any location.

RESULTS

The external iliac (43%) and obturator (26%) regions and the parametrium (21%) were the most commonly involved pelvic lymph node sites with solitary metastases. Isolated metastases to common iliac, presacral (internal iliac), and paraaortic nodes were found in 7%, 1%, and 1% of patients, respectively. Patients with 2 positive nodes had 1 parametrial and 1 pelvic node involved (32%), 2 ipsilateral positive nodes (31%), 1 positive lymph node on both sides of the pelvis (27%), and 2 positive nodes within the parametrium (10%).

CONCLUSIONS

In cervical cancer patients with only 1 positive lymph node, this node is most frequently located within the external iliac and obturator regions and the parametrium. Sentinel node identification should primarily address these lymph node sites. If 1 positive lymph node is found, further metastases are unpredictable within pelvic and parametrial lymph node sites. Paraaortic spread without pelvic node involvement is rare.

The sentinel concept in patients with cervical cancer

The sentinel concept for patients with early cervical cancer has a high potential for decreasing morbidity and for increasing oncologic safety. The detection rate with technetium-labeling or a combination with blue dye varies between 84% and 92%. Sensitivity and negative predictive value depend on tumor size: the smaller the tumor, the higher the validity of the technique. Detection of circulating tumor cells in the sentinel node using HPVmRNA as marker may have a good prognostic value. Currently the sentinel concept should only be used in clinical studies before its validity has been proved.