The sentinel concept in patients with cervical cancer

Sentinel lymph node biopsy alone in the management of early cervical carcinoma

OBJECTIVE

Sentinel lymph node (SLN) biopsy aims to assess lymph node status with reduced surgical morbidity. The aim of the study was to determine the accuracy and safety of SLN biopsy in the management of early cervical carcinoma using a double technique (technetium-99m (Tc-99m) nanocolloid and methylene blue dye injection).

METHODS

This was a 10-year study from January 2009 to January 2019 that recruited 103 consecutive women undergoing surgery for early cervical carcinoma, FIGO 2009 stage IA1 (grade 3, and grade 2 with lymphovascular space invasion) to IB1 (<2 cm), at the West Kent Gynaecological Oncology Centre, Maidstone, UK. All patients were given the choice of pelvic node dissection and SLN mapping or SLN only. All patients elected to undergo SLN only. In total 97 patients had SLN mapping performed laparoscopically. We used the combined method (Tc-99m nanocolloid and/or methylene blue dye). All SLN routinely underwent ultrastaging.

RESULTS

At least one SLN was detected in all 103 patients, using at least one of the combined methods (Tc-99m nanocolloid or blue dye). Bilaterally SLN were removed in 85/103 women with an 83% bilateral detection rate. The median SLN count was 2.3 (range 1-6) nodes. Of 103 patients, 7 (6.7%) patients had lymph node involvement. There were no pelvic or para-aortic lymph node recurrences with a median follow-up of 53 (range 8-120) months. The specificity and negative predictive value of a negative SLN was 100%. None of our 103 patients reported lower extremity lymphedema.

CONCLUSION

In carefully selected patients with early cervical carcinoma, SLN biopsy alone appears to be a safe method for lymph node assessment of women undergoing surgical staging. Ultrastaging is an essential part of histologic examination of SLN.

Location of Sentinel Lymph Node in Cervical Carcinoma and Factors Associated With Unilateral Detection

OBJECTIVE

The aims of this study were to assess locality of the sentinel lymph node (SLN) in cervical carcinoma and examine factors affecting bilateral SLN detection.

METHODS

This was a retrospective review of SLN data (anatomical location, count and laterality) in patients with early-stage cervical cancer (International Federation of Gynecology and Obstetrics stage IA1 with lymphovascular space invasion to stage IIA) using intraoperative gamma probe and blue dye. The preoperative single-photon emission computed tomography with computed tomography was used to detect laterality, number of the SLNs, and rare locations. Patients were treated between January 2005 to January 2015 at the West Kent Gynaecological Oncology Centre, Maidstone Hospital, Maidstone, United Kingdom.

RESULTS

A total of 132 women were investigated. The most common SLN location was the external iliac (38.6%) followed by obturator (25.3%) and internal iliac (23.6%) regions. A small percentage was identified in presacral (1.4%) and para-aortic regions (0.7%). Older age (P = 0.01) and an elevated body mass index (P = 0.03) were associated with decreased SLN count by preoperative single-photon emission computed tomography with computed tomography, and only age affected SLN count by gamma probe (P = 0.01). Initial surgery, large loop excision of the transformation zone, or cone biopsy of the cervix had no effect on SLN count. There was no difference observed in bilateral detection with respect to surgical approach (open: n = 48/laparoscopic: n = 84). However, older age was independently associated with a decrease in bilateral SLN detection (P = 0.003). In these patients who underwent unilateral full pelvic lymphadenectomy, all the nonsentinel nodes were negative.

CONCLUSIONS

The majority of SLNs were located in the external iliac, obturator, and internal iliac regions. Both older age and an elevated body mass index were associated with a reduced SLN count. Unilateral detection of SLN was independently associated with older age, which may be due to sclerosis in the lymphatic vessels or reduced perfusion in the pelvis in these women. If no SLN is detected on one side, the consensus is to perform a full pelvic lymphadenectomy on that side of the pelvis.

Value and advantages of preoperative sentinel lymph node imaging with SPECT/CT in cervical cancer

OBJECTIVE

Precise detection of sentinel lymph nodes (SLNs) seems to be a crucial factor for optimized treatment of cervical cancer. We assess the use of single photon emission computed tomography combined with computed tomography (SPECT/CT) as an alternative to lymphoscintigraphy (LSG) for preoperative identification of SLN.

METHODS

This study was performed in a prospective, unicentric setting. Patients with cervical carcinoma were scheduled for surgery and additional SLN labeling by peritumoral injection of 10 MBq technetium-99m-nanocolloid and patent blue. Thirty minutes after injection, LSG and SPECT/CT were carried out. We evaluated the number of SLNs detected intraoperatively in LSG and SPECT/CT and the histologic findings of SLN and non-SLN. Subsequently, we determined the impact of these results on the therapeutic approach.

RESULTS

This represents the largest study about SPECT/CT for SLN detection in cervical cancer so far. Between August 2008 and March 2013, 59 cervical cancer patients underwent intraoperative SLN detection. In addition, 51 of these patients underwent preoperative LSG and SPECT/CT. Imaging with SPECT/CT detected singular SLN at significantly higher rate (47/51, 92.2%) than that with planar LSG (43/51, 84.3%, P = 0.044). Furthermore, SPECT/CT performed better than LSG regarding the total number of detected SLN (SPECT/CT median, 3 [0-18]; LSG median, 2 [0-15]) and detection rates per pelvic side (SPECT/CT 76.9%, LSG 69.2%, P < 0.01). Whenever SLN detection succeeded, histologic evaluation of SLN correctly predicted the lymph node status per patient's side. Using this type of diagnostic approach for lymph node staging, we reached sensitivity of 100% and negative predictive value of 100% at a rate of false-negative results of 0% even in tumors larger than 4 cm.

CONCLUSIONS

Single photon emission computed tomography combined with computed tomography imaging leads to improved rates of SLN detection and better anatomic correlation compared with planar LSG. Thus, intraoperative detection of SLN can be improved by preoperative SPECT/CT imaging. This enhances the clinical value of SLN technique and improves the oncologic safety of SLN concept.

Detection of sentinel lymph nodes in minimally invasive surgery using indocyanine green and near-infrared fluorescence imaging for uterine and cervical malignancies

OBJECTIVES

Our primary objective was to assess the detection rate of sentinel lymph nodes (SLNs) using indocyanine green (ICG) and near-infrared (NIR) fluorescence imaging for uterine and cervical malignancies.

METHODS

NIR fluorescence imaging for the robotic platform was obtained at our institution in 12/2011. We identified all cases planned for SLN mapping using fluorescence imaging from 12/2011-4/2013. Intracervical ICG was the fluorophobe in all cases. Four cc (1.25mg/mL) of ICG was injected into the cervix alone divided into the 3- and 9-o'clock positions, with 1 cc deep into the stroma and 1 cc submucosally before initiating laparoscopic entry. Blue dye was concurrently injected in some cases.

RESULTS

Two hundred twenty-seven cases were performed. Median age was 60 years (range, 28-90 years). Median BMI was 30.2 kg/m(2) (range, 18-60 kg/m(2)). The median SLN count was 3 (range, 1-23). An SLN was identified in 216 cases (95%), with bilateral pelvic mapping in 179 (79%). An aortic SLN was identified in 21 (10%) of the 216 mapped cases. When ICG alone was used to map cases, 188/197 patients mapped, for a 95% detection rate compared to 93% (28/30) in cases in which both dyes were used (P=NS). Bilateral mapping was seen in 156/197 (79%) ICG-only cases and 23/30 (77%) ICG and blue dye cases (P=NS).

CONCLUSIONS

NIR fluorescence imaging with intracervical ICG injection using the robotic platform has a high bilateral SLN detection rate and appears favorable to using blue dye alone and/or other modalities. Combined use of ICG and blue dye appears unnecessary.

A prospective single-center study of sentinel lymph node detection in cervical carcinoma: is there a place in clinical practice?

OBJECTIVE

To establish the accuracy of sentinel lymph node (SLN) detection in early cervical cancer.

MATERIALS AND METHODS

Sentinel lymph node detection was performed prospectively over a 6-year period in 86 women undergoing surgery for cervical carcinoma by the combined method (Tc-99m and methylene blue dye). Further ultrastaging was performed on a subgroup of 26 patients who had benign SLNs on initial routine histological examination.

RESULTS

The SLN was detected in 84 (97.7%) of 86 women by the combined method. Blue dye uptake was not seen in 8 women (90.7%). Sentinel lymph nodes were detected bilaterally in 63 women (73.3%), and the external iliac region was the most common anatomic location (48.8%). The median SLN count was 3 nodes (range, 1-7). Of the 84 women with sentinel node detection, 65 also underwent bilateral pelvic lymph node dissection, and in none of these cases was a benign SLN associated with a malignant non-SLN (100% negative predictive value). The median non-SLN count for all patients was 19 nodes (range, 8-35). Eighteen patients underwent removal of the SLN without bilateral pelvic lymph node dissection. Nine women (10.5%) had positive lymph nodes on final histology. One patient had bulky pelvic nodes on preoperative imaging and underwent removal of the negative bulky malignant lymph nodes and a benign SLN on the contralateral side. This latter case confirms the unreliability of the SLN method with bulky nodes. The remaining 8 patients had positive SLNs with negative nonsentinel lymph nodes. Fifty-nine SLNs from 26 patients, which were benign on initial routine histology, underwent ultrastaging, but no further disease was identified. Four patients (5%) relapsed after a median follow-up of 28 months (range, 8-80 months).

CONCLUSION

Sentinel lymph node detection is an accurate and safe method in the assessment of nodal status in early cervical carcinoma.

Changes in pulse oximetry after patent blue dye injection into the uterine cervix

BACKGROUND

To evaluate changes in pulse oximetry readings in patients with cervical carcinoma after the injection of patent blue dye into the uterine cervix for sentinel lymph node detection.

METHODS

Fifty-six patients underwent radical hysterectomy and bilateral pelvic lymphadenectomy for the treatment of International Federation of Gynecology and Obstetrics stage I or II cervical cancer. Four milliliters of patent blue dye were injected into the cervix. On the eve of surgery, all patients also received an injection of Dextran 500 labeled with technetium 99 m (Tc-99 m Dextran, 600 to 800 muCi) into the cervix and subsequently underwent pelvic lymphoscintigraphy.

RESULTS

Of the 56 patients, 1 (1.79%) had an anaphylactic reaction, and in 13 (23.22%), pulse oximetry readings were <96%. The lowest median pulse oximetry reading in these patients was 87%. Pulse oximetry readings began to decrease between 2 and 10 minutes after patent blue dye injection into the cervix and lasted for approximately 5 minutes. No changes in blood pressure, heart rate, or electrocardiogram were found during the period in which this alteration was recorded by the pulse oximeter.

CONCLUSION

The decrease in pulse oximetry readings after patent blue dye injection into the cervix was associated with larger tumors and tumors that surrounded the external cervical os.

Lymphatic mapping and sentinel node biopsy in gynecological cancers: a critical review of the literature

Although it does not have a long history of sentinel node evaluation (SLN) in female genital system cancers, there is a growing number of promising study results, despite the presence of some aspects that need to be considered and developed. It has been most commonly used in vulvar and uterine cervivcal cancer in gynecological oncology. According to these studies, almost all of which are prospective, particularly in cases where Technetium-labeled nanocolloid is used, sentinel node detection rate sensitivity and specificity has been reported to be 100%, except for a few cases. In the studies on cervical cancer, sentinel node detection rates have been reported around 80–86%, a little lower than those in vulva cancer, and negative predictive value has been reported about 99%. It is relatively new in endometrial cancer, where its detection rate varies between 50 and 80%. Studies about vulvar melanoma and vaginal cancers are generally case reports. Although it has not been supported with multicenter randomized and controlled studies including larger case series, study results reported by various centers around the world are harmonious and mutually supportive particularly in vulva cancer, and cervix cancer. Even though it does not seem possible to replace the traditional approaches in these two cancers, it is still a serious alternative for the future. We believe that it is important to increase and support the studies that will strengthen the weaknesses of the method, among which there are detection of micrometastases and increasing detection rates, and render it usable in routine clinical practice.

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.