Unusual localizations of sentinel lymph nodes in early stage cervical cancer: a review

Finding the sentinel lymph node in early cervical cancer: When is unusual not uncommon?

OBJECTIVE

To report our institutional experience with sentinel lymph node (SLN) detection using indocyanine green for cervical cancer, in terms of detection rates, detection of SLN at unusual locations, and factors associated with unusual SLN locations. In addition, we performed a systematic review of the literature to identify factors associated with unusual SLN localizations.

METHODS

This is a retrospective cohort study of women with early-stage cervical cancer undergoing sentinel lymph node mapping between 2015 and 2019. Outcome measures were SLN detection rates, detection rates of unusual locations for SLN and risk factors for aberrant lymphatic drainage pathways. In addition, studies evaluating factors associated with unusual SLN locations in cervical cancer were assessed in a systematic review.

RESULTS

A total of 100 patients were included. The unilateral SLN detection rate was 88%, whereas the bilateral detection rate was 75%. In 37% of all patients, SLN were found in unusual locations, and in 10% of patients SLN were solely found in unusual locations. Body mass index (BMI) was associated with finding SLN in unusual locations, with unusual nodes detected in 52% of patients with BMI <25 kg/m² and in 28% of patients with BMI ≥25 kg/m². The systematic review identified three studies, identifying lower BMI, nulliparity and tumor size of >20 mm as factors associated with finding SLN at unusual locations.

CONCLUSION

Aberrant drainage sites represent a significant proportion of SLN detected in cervical cancer. Factors associated with increased rates of unusual nodal locations are a lower BMI, with a possible association with nulliparity and tumor size of >20 mm.

Incidence of metastasis in circumflex iliac nodes in patients with cervical cancer: a systematic review

OBJECTIVE

The circumflex iliac nodes distal to the external iliac nodes are frequently removed when bilateral pelvic lymphadenectomy is performed in patients with cervical cancer. The objective of this systematic review was to assess the incidence of metastasis in the circumflex iliac nodes in patients with cervical cancer.

METHODS

PubMed/Medline, ClinicalTrials, Embase, Cochrane Central Register of Controlled Trials, Scopus, and Ovid databases were searched from inception to May 2021. We included articles published in English language reporting all types of studies, except for case reports and commentaries. Abstracts and unpublished studies were excluded. The inclusion criteria were diagnosis of cervical cancer, FIGO 2009 stages IA-IIB, squamous cell carcinoma, adenocarcinoma or adenosquamous carcinoma, and primary surgery including pelvic lymph node dissection.

RESULTS

A total of 3037 articles were identified. Overall, 1165 eligible patients from four studies were included in the analysis. A total of 696 (59.7%) patients had early-stage disease (FIGO 2009 stages IA, IB1, IIA1). The median number of extracted circumflex iliac nodes, which was reported in two studies, was one (range not reported) and three (range 1-13). The positive lymph node rate for the entire population and circumflex iliac node involvement were 26.9% and 3.1%, respectively. Isolated metastases were reported for 904 patients (three studies) and in one patient nodal spread was detected (0.11%).

CONCLUSION

The rate of isolated metastases in circumflex iliac nodes is small and excision of these lymph nodes as part of routine lymphadenectomy should be avoided.

Post-operative small pelvic field radiation therapy in patients with intermediate risk early stage cervix cancer: a safe and efficient treatment modality

Background

The treatment of early stage cervical cancer has different therapeutic options. Adjuvant external beam radiotherapy for surgically treated intermediate risk cervical cancer patients has shown acceptable oncological outcomes with a low incidence of toxicity. The aim of this study was to analyze the oncological outcomes and safety of adjuvant small pelvic field radiotherapy in surgically treated stage IB1-2 cervical cancer patients who met the Sedlis intermediate-risk criteria.

Materials and methods

A retrospective cohort study was carried out with 28 patients treated from 2007 to November 2019 with biopsy proven intermediate risk stage IB1–2 cervical cancer previously treated with radical hysterectomy and bilateral lymphadenectomy who received adjuvant small pelvic field radiotherapy. The primary endpoints were local and distant control and overall survival. Secondary endpoints were acute and late gastrointestinal and genitourinary toxicity. Survival curves were analyzed using the Kaplan-Meier method.

Results

After a median follow up period of 41.5 (27.5–80.5) months, adjuvant small pelvic field radiotherapy showed a 100% overall survival rate, 81.82% disease free survival and 86.36% local recurrence-free survival with no incidence of grade 3 or 4 acute or late toxicity. Three patients suffered from relapse, 1 in the vaginal cuff, 1 in the retrovesical area and 1 patient in the retroperitoneal area.

Conclusions

Adjuvant small pelvic field radiotherapy is an efficient and safe treatment option that offers excellent oncological outcomes to surgically treated intermediate-risk stage IB1–2 cervical cancer patients with an excellent toxicity profile.

Sentinel lymph node mapping in early-stage cervical cancer - A national prospective multicenter study (SENTIREC trial)

OBJECTIVES

Sentinel lymph node (SLN) mapping may replace staging radical pelvic lymphadenectomy in women with early-stage cervical cancer. In a national multicenter setting, we evaluated SLN mapping in women with early-stage cervical cancer and investigated the accuracy of SLN mapping and FDG-PET/CT in tumors >20 mm.

METHODS

We prospectively included women with early-stage cervical cancer from March 2017-January 2021 to undergo SLN mapping. Women with tumors >20 mm underwent completion pelvic lymphadenectomy and removal of FDG-PET/CT positive nodes. We determined SLN detection rates, incidence of nodal disease, sensitivity and negative predictive value (NPV) of SLN mapping, and the sensitivity, specificity, NPV, and positive predictive value (PPV) of FDG-PET/CT.

RESULTS

We included 245 women, and 38 (15.5%) had nodal metastasis. The SLN detection rate was 96.3% (236/245), with 82.0% (201/245) bilateral detection. In a stratified analysis of 103 women with tumors >20 mm, 27 (26.2%) had nodal metastases. The sensitivity of SLN mapping adhering to the algorithm was 96.3% (95% CI 81.0-99.9%) and the NPV 98.7% (95% CI 93.0-100%). For FDG-PET/CT imaging the sensitivity was 14.8% (95% CI 4.2-33.7%), the specificity 85.5% (95% CI 75.6-92.5%), the NPV 73.9% (95% CI 63.4-82.7%), and the PPV 26.7% (95% CI 7.8-55.1%).

CONCLUSIONS

SLN mapping seems to be an adequate staging procedure in early-stage cervical cancer tumors ≤20 mm. In tumors >20 mm, SLN mapping is highly sensitive but demands full adherence to the SLN algorithm. We recommend completion pelvic lymphadenectomy in tumors >20 mm until the oncological safety is established. FDG-PET/CT for nodal staging of women with early-stage cervical cancer seems limited.

Report from the European Society of Gynaecological Oncology (ESGO) 2020 State-of-the-Art Virtual Meeting

This is a report from the European Society of Gynaecological Oncology State-of-the-Art Virtual Meeting held December 14-16, 2020. The unique 3-day conference offered comprehensive state-of-the-art summaries on the major advances in the treatment of different types of gynecological cancers. Sessions opened with a case presentation followed by a keynote lecture and interactive debates with opinion leaders in the field. The speakers also presented scientific reviews on the clinical trial landscape in collaboration with the European Network of Gynecological Oncological Trial (ENGOT) groups. In addition, the new ESGO-ESRTO-ESP endometrial cancer guidelines were officially presented in public. This paper describes the key information and latest studies that were presented for the first time at the conference.

Region-specific Risk Factors for Pelvic Lymph Node Metastasis in Patients with Stage IB1 Cervical Cancer

Objectives: We aimed to identify the risk factors associated with pelvic lymph node metastasis (LNM) at each anatomic location in patients with stage IB1 cervical cancer.

Methods: A primary cohort of 728 patients with stage IB1 cervical cancer who underwent radical hysterectomy and systematic pelvic lymphadenectomy were retrospectively studied. All removed pelvic nodes (N=20,134) were pathologically examined. The risk factors for LNM in different anatomic regions (obturator, internal iliac, external iliac, and common iliac) were evaluated by multivariate logistic regression analyses. Nomograms were generated from the primary cohort and validated in another external cohort (N=242). The performance of the nomogram was assessed by its calibration and discrimination. Overall survival and progression-free survival in patients with different LNM patterns were compared.

Results: LNM was found in 266 (1.3%) removed nodes and 106 (14.6%) patients. The incidences of LNM at the obturator, internal iliac, external iliac, common iliac, and parametrial regions were 8.5%, 5.4%, 4.7%, 1.9% and 1.8%, respectively. Among others, tumour size and lymph-vascular space invasion (LVSI), which are preoperatively assessable, were identified as independent risk factors of LNM in the common iliac region and the lower pelvis, respectively, and age was an additional independent risk factor of obturator LNM. The negative predictive values of tumour size <2 cm for common iliac LNM and negative LVSI combined with older age (> 50 years) for obturator LNM were 100% and 98.7%, respectively. A nomogram of these two factors showed good calibration and discrimination (concordance index, 0.761 in the primary cohort and 0.830 in validation cohort). The patients with common iliac LNM had poorer survival than those with LNM confined to the lower pelvis, while the differences in survival between patients with LNM confined to one node, one region or single side and those with more widely spreading LNM were not statistically significant.

Conclusions: Tumour size, LVSI and age are region-specific risk factors for pelvic LNM in IB1 cervical cancer, which could be used to allocate the appropriate extent of pelvic lymphadenectomy.

Detection of sentinel lymph node in laparoscopic surgery for uterine cervical cancer using carbon nanoparticles

BACKGROUND AND OBJECTIVES

Carbon nanoparticles (CNPs) has been widely confirmed the efficiency in sentinel lymph node (SLN) mapping for various solid tumors. This study aims to explore the feasibility and effectiveness of CNPs during laparoscopic surgery for cervical cancer.

METHODS

We analyzed 45 women with stage IB1-IIA1 cervical cancer who underwent SLN mapping using CNPs during laparoscopic surgery. The effectiveness of CNPs was evaluated by the detection rate and accuracy parameters. Factors associated with SLN laterality and SLNs localizations were analyzed.

RESULTS

The overall and bilateral detection rate was 93.3% (42/45) and 60.0% (27/45), respectively. Elevated body mass index was associated with decreased bilateral detection rate (P = .015). A total of 225 SLNs were harvested, with a mean number of 5.0 ± 3.6. A total of 81.3% of SLNs were in expected localizations including external iliac (39.1%), internal iliac (25.8%), and obturator (16.4%) regions, while 18.7% in unusual localizations including common iliac (10.7%), parametrial (7.6%), and presarcal (0.4%) regions. None positive lymph node was found in non-SLNs with a false-negative rate of 0%.

CONCLUSION

Laparoscopic SLN mapping with CNPs appears to be simple and efficient for patients with early-stage cervical cancer.

Does the Sentinel Lymph Node Sampling Alone Improve Quality of Life in Early Cervical Cancer Management?

Objective: In this subanalysis of the prospective randomized multicenter SENTICOL 2 study, we compared the quality of life (QoL), in two arms, in association with lower-limb consequences in women with early stage cervical cancer undergoing randomized sentinel lymph node (SLN) sampling alone or SLN sampling and full pelvic lymphadenectomy. Methods: 206 patients with an early stage cervical cancer and a negative SLN, were randomized. Every patient had a SLN detection based on a combination of radio-isotope (Nanocis®) and blue dye (Bleu Patenté®) injections. One hundred and One patients, the "standard" group, had complete pelvic lymphadenectomy, 105 patients, the "SLN alone" group, had SLN biopsy without lymphadenectomy. At each visit (V0: preoperative, V1: 1 month, V2: 3 months and V3: 6 months following surgery) the patients completed a Short Form Health Survey (SF36) questionnaire and another questionnaire related to leg lymphedema. SF36 scores variations (compared to the baseline values) were assessed with a standard analysis and by an evaluation of the area under the curve (AUC). Several lower-limb circumferences and signs were also determined. Results: General characteristics of the patients were well-balanced between groups. Physical function and general health dimensions of the SF36 scale were significantly improved at V1 and V2 in the "SLN alone" group. Mental health was also statistically better in the "SLN alone" group at V2. Other dimensions were similar. The two groups had similar evaluation at V3. AUC of SF36 sub-scores was also in favor of the "SLN alone" arm, but the difference was not statistically significant. The analysis about the lymphedema of the legs showed a reduced (but not significant) risk in the "SLN alone" group for the top-of-thigh and the mid-thigh perimeters. Lymphedema symptoms reported by the patients were significantly less severe in the "SLN alone" group. Conclusion: Our study demonstrates a trend for a better quality of life and less severe leg heaviness and leg fatigue when a full pelvic lymphadenectomy is avoided.

Superparamagnetic iron oxide as a tracer for sentinel lymph node detection in uterine cancer: a pilot study

Sentinel lymph node (SLN) mapping using dye or radioisotopes has been performed in patients with uterine cancer. Superparamagnetic iron oxide (SPIO) can be handled safely and is taken up by lymph nodes (LNs); however, its efficacy in detecting SLNs in uterine cancer remains unknown. This pilot study evaluated the use of SPIO as a tracer for SLN detection in patients with uterine cancer. SPIO was injected into the uterine cervixes of 15 patients with uterine cancer scheduled for pelvic LN dissection. Magnetic resonance imaging (MRI) was performed preoperatively. Five patients also underwent radioisotope injection and single-photon emission computed tomography/computed tomography. Dissected LNs were stained with iron and examined pathologically. Of the radioisotope-positive LNs, 92% were also SPIO/MRI-positive. SPIO/MRI and iron staining were positively correlated. SLNs were identified by iron staining in 93% of cases. Iron staining was strongly positive in two of the five areas of LN metastasis; these were considered SLNs. Staining was negative or very weak in the other three areas and lymph flow disturbance was considered. SPIO and radioisotopes are taken up similarly by SLNs. SPIO/MRI and iron staining may thus be useful for detection of SLNs and diagnosis of LN metastasis in patients with uterine cancer.

[Sentinel lymph node biopsy in early-stage cervical cancer: current state of art]

Lymph node status is the most important prognostic factor of survival in women with early stage cervical cancer. Sentinel lymph node (SLN) biopsy is an accurate method for the assessment of lymph nodal involvement in early-stages cervical cancer and has been increasingly used instead of systematic pelvic lymph node dissection (PLND). Less-radical lymph node dissection decreases the associated morbidity of PLND, especially the risk of lower-leg lymphoedema, which affects severely patient quality of life. SLN biopsy allows nodes ultrastaging and provides supplementary histological information by increasing the detection of tumor low-volume (isolated tumors cells and micrometastases). Moreover, SLN biopsy provides accurate anatomical information on pelvic lymphatic drainage pathway by identifying nodes outside of routine lymphadenectomy areas. Selection of a population at low-risk of nodal metastasis, a minimal training, and simple rules may ensure a low false negative rate. Several studies have shown that SLN mapping in these patients is feasible, with excellent detection rates and sensitivity. Combined detection with technetium-99 and blue dye has been widely used but recently, there has been increasing interest in the use of fluorescent dies such as indocyanine green (ICG) which would improve SLN detection. Although recent international guidelines recommend performing SLN biopsy in addition to PLND, SLN biopsy alone is not the gold-standard yet due to lack of prospective evidence, especially on long-term oncological safety. Some points remain controversial such as the low accuracy of intraoperative SLN status assessment by frozen section and the impact of micrometastasis on prognostic. The prospective randomized clinical trial SENTICOL III will answer to these problematics.

The analysis of the long-term outcomes in elderly women treated for locally advanced cervical cancer

Purpose

Locally advanced cervical cancer (LACC) should be treated with a combination of external irradiation and brachytherapy with concurrent chemotherapy. However, as cervical carcinoma cells can disperse by way of the lymphatic system to either pelvic or para-aortic nodes, planning the extent of radiation requires precise information about the spread of the disease to the lymph nodes, especially to the para-aortic area.

Material and methods

All of the 75 women included in our study underwent chemoradiotherapy, which started with brachytherapy. Out of them, 54 have undergone radical hysterectomy with lymphadenectomy followed by chemoradiation. We have retrospectively analyzed the 5-year overall survival (OS) rates relative to the lymph node involvement, the type of lymphadenectomy performed (pelvic, para-aortic, or both), the size of the tumor (> or < 4 cm), the histological type, grading, and the age of patients.

Results

We observed significant differences in the OS rates relative to the age of the patients with LACC. We noted significant differences in the OS rates related to para-aortic lymphadenectomy and presence of lymph node metastases.

Conclusions

Para-aortic lymphadenectomy seems to have a positive influence on long-term outcomes in the LACC patients, and elderly patients may benefit more from applied therapy.

Cervical cancer treated with reduced-volume intensity-modulated radiation therapy base on Sedlis criteria (NCCN VS RTOG)

OBJECTIVE

This study aimed to evaluate the clinical efficacy of different target volumes in pelvic radiotherapy in postoperative treatment of cervical cancer based on the Sedlis criteria.

METHODS

Patients who admitted to our department for post-operative radiotherapy of cervical cancer from December 2001 to December 2011 and met the Sedlis criteria were retrospectively analysed. The incidences of acute and late radiation injuries, and overall, disease-free and tumour-specific survival with reduced-volume pelvic and whole-pelvis radiotherapy were evaluated and compared.

RESULTS

A total of 371 patients were included in the study, including 239 receiving whole-pelvis radiotherapy and 132 receiving reduced-volume pelvic radiotherapy. The volume of contours for mean PTV volumes, bilateral femoral heads and small intestine volumes in reduced-volume pelvic radiotherapy were lower than whole-pelvis radiotherapy; the results were similar to the V10, V20, V30, V40 and V45 for pelvic bone marrow and small intestine dose volume (both p < 0.05). The acute radiation injury observed in the two groups was mainly haematologic toxicity and upper and lower gastrointestinal symptoms. The incidences of acute radiation injury, and late radiation injury of gastrointestinal and urinary tracts were both significantly lower with reduced-volume pelvic radiotherapy than with whole-pelvis radiotherapy (both p < 0.05). Moreover, there was no significant difference in the incidence of lower extremity oedema, or 2-year or 5-year overall, disease-free or tumour-specific survival between groups (all p > 0.05).

CONCLUSION

Reduced-volume pelvic radiotherapy could relieve acute and late radiation injuries, especially myelosuppression, and did not affect long-term survival. Advanced in knowledge: Our study shows that reduced-volume base on National Comprehensive Cancer Network 2016 is more fit for cervical cancer than others.

Application of carbon nanoparticles in laparoscopic sentinel lymph node detection in patients with early-stage cervical cancer

Objective

To investigate the value of carbon nanoparticles in identifying sentinel lymph nodes in early-stage cervical cancer.

Methods

From January 2014 to January 2016, 40 patients with cervical cancer stage IA2–IIA, based on the International Federation of Gynecology and Obstetrics (FIGO) 2009 criteria, were included in this study. The normal cervix around the tumor was injected with a total of 1 mL of carbon nanoparticles (CNP)at 3 and 9 o'clock. All patients then underwent laparoscopic pelvic lymph node dissection and radical hysterectomy. The black-dyed sentinel lymph nodes were removed for routine pathological examination and immunohistochemical staining.

Results

Among the 40 patients, 38 patients had at least one sentinel lymph node (SLN). The detection rate was 95% (38/40). One hundred seventy-three SLNs were detected with an average of 3.9 SLNs per side. 25 positive lymph nodes, which included 21 positive SLNs, were detected in 8 (20%) patients. Sentinel lymph nodes were localized in the obturator (47.97%), internal lilac (13.87%), external lilac (26.59%), parametrial (1.16%), and common iliac (8.67%) regions. The sensitivity of the SLN detection was 100% (5/5), the accuracy was 97.37% (37/38), and the negative predictive value was 100. 0% and the false negative rate was 0%.

Conclusions

Sentinel lymph nodes can be used to accurately predict the pathological state of pelvic lymph nodes in early cervical cancer. The detection rates and accuracy of sentinel lymph node were high. Carbon nanoparticles can be used to trace the sentinel lymph node in early cervical cancer.

Incidence of metastasis in circumflex iliac nodes distal to the external iliac nodes in cervical cancer

OBJECTIVE

A causal relationship between removal of circumflex iliac nodes distal to the external iliac nodes (CINDEIN) and lower leg edema has been recently suggested. The aim of this study was to elucidate the incidence of CINDEIN metastasis in cervical cancer.

METHODS

A retrospective chart review was carried out for 531 patients with cervical cancer who underwent lymph node dissection between 1993 and 2014. CINDEIN metastasis was pathologically identified by microscopic investigation. After 2007, sentinel lymph node biopsy was performed selectively in patients with non-bulky cervical cancer. The sentinel node was identified using (99m)Tc-phytate and by scanning the pelvic cavity with a γ probe.

RESULTS

Two hundred and ninety-seven patients (55.9%) underwent CINDEIN dissection and 234 (44.1%) did not. The percentage of International Federation of Gynecology and Obstetrics stage IIb to IV (42.4% vs. 23.5%, p<0.001) was significantly higher in patients who underwent CINDEIN dissection than those who did not. CINDEIN metastasis was identified in 1.9% overall and in 3.4% of patients who underwent CINDEIN dissection. For patients with stage Ia to IIa disease, CINDEIN metastasis was identified in 0.6% overall and in 1.2% of patients who underwent CINDEIN dissection. Of 115 patients with sentinel node mapping, only one (0.9%) had CINDEIN detected as a sentinel node. In this case, the other three lymph nodes were concurrently detected as sentinel lymph nodes.

CONCLUSION

CINDEIN dissection can be eliminated in patients with stage Ia to IIa disease. CINDEIN might not be regional lymph nodes in cervical cancer.

Radical hysterectomy with or without para-aortic lymphadenectomy for patients with stage IB2, IIA2, and IIB cervical cancer: outcomes for a series of 308 patients

BACKGROUND

Although many studies have already shown that lymph node metastasis is one of the major prognostic factors for cervical cancer, the therapeutic significance of para-aortic lymphadenectomy for the surgical treatment of cervical cancer remains controversial.

METHODS

A total of 308 patients diagnosed with stage IB2, IIA2, or IIB cervical cancer and treated with radical hysterectomy were retrospectively investigated to assess the incidence of para-aortic lymph node metastasis and the clinicopathological factors linked to cervical cancer prognosis.

RESULTS

Para-aortic lymph node metastases were pathologically confirmed in 13 of the 136 patients (9.6 %) who underwent para-aortic lymphadenectomy. The incidence of para-aortic lymph node metastasis was significantly higher in the patients who had common iliac lymph node metastases (odds ratio 31.5, p < 0.001) according to logistic regression analysis. Common iliac lymph node metastasis was related to risk of recurrence (hazard ratio 2.43, p = 0.003) and death (hazard ratio 2.62, p = 0.007) in Cox regression analysis. Kaplan-Meier analysis and Cox regression analysis showed that para-aortic lymphadenectomy did not have a positive impact on survival in 308 patients or 140 pN1 patients, but para-aortic lymphadenectomy was related to better overall survival with a marginal trend toward significance (p = 0.053) in 30 patients with common iliac lymph node metastasis.

CONCLUSIONS

Indication for para-aortic lymphadenectomy in the surgical treatment of stage IB2, IIA2, or IIB cervical cancer needs to be individualized. Patients with common iliac lymph node metastasis are possible candidates, and a prospective study is needed to clarify this issue.

Sentinel node biopsy for lymph nodal staging of uterine cervix cancer: a systematic review and meta-analysis of the pertinent literature

BACKGROUND

We reviewed the available literature on the accuracy of sentinel node mapping in the lymph nodal staging of uterine cervical cancers.

METHODS

MEDLINE and Scopus were searched by using "sentinel AND (cervix OR cervical)" as key words. Studies evaluating the accuracy of sentinel node mapping in the lymph nodal staging of uterine cervical cancers were included if enough data could be extracted for calculation of detection rate and/or sensitivity.

RESULTS

Sixty-seven studies were included in the systematic review. Pooled detection rate was 89.2% [95% CI: 86.3-91.6]. Pooled sensitivity was 90% [95% CI: 88-92]. Sentinel node detection rate and sensitivity were related to mapping method (blue dye, radiotracer, or both) and history of pre-operative neoadjuvant chemotherapy. Sensitivity was higher in patients with bilaterally detected pelvic sentinel nodes compared to those with unilateral sentinel nodes. Lymphatic mapping could identify sentinel nodes outside the routine lymphadenectomy limits.

CONCLUSION

Sentinel node mapping is an accurate method for the assessment of lymph nodal involvement in uterine cervical cancers. Selection of a population with small tumor size and lower stage will ensure the lowest false negative rate. Lymphatic mapping can also detect sentinel nodes outside of routine lymphadenectomy areas providing additional histological information which can improve the staging. Further studies are needed to explore the impact of sentinel node mapping in fertility sparing surgery and in patients with history of neoadjuvant chemotherapy.

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.