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

Abdominal radical trachelectomy guided by sentinel lymph node biopsy for stage IB1 cervical cancer with tumors >2 cm

Accuracy of prediction of pelvic lymph node status using sentinel lymph node biopsy (SLNB), and outcomes of SLNB-guided abdominal radical trachelectomy (ART) were assessed. Patients with stage IB1 (Figure 2009) cervical cancer and with tumors >2 cm were enrolled. Prior to fertility-sparing surgery 99mTc-labeled phytate was administered. SLNs were intraoperatively identified, excised, and assessed using fast-frozen sections. Systematic bilateral pelvic lymphadenectomy with or without para-aortic lymphadenectomy was subsequently undertaken. The SLN detection rate was 91.8% (45/49 patients); 8.2% (4/49) had radical hysterectomies because of metastatic primary SLNs. All SLNs received routine immunopathological examination to detect micrometastasis. Sensitivity, accuracy, and false negative rates were 100%, 100%, and 0%, respectively. ART was successfully completed in 45 patients (median follow-up, 61 [range, 4-149] months). Three of the 45 (6.7%) were lost to follow-up; two relapsed and one died of tumor progression. Overall 3-year survival and progression-free survival rates were 97.6% and 95.2%, respectively. Of the 19 patients who attempted to conceive after surgery, five achieved pregnancy, and one had a live birth in the third trimester. We concluded that SLNB using 99mTc-labeled phytate can accurately assess pelvic node status. SLNB-guided ART is safe and feasible in patients selected for fertility-sparing procedures.

Utility of Laparoscopic Indocyanine Green-Guided Sentinel Node Biopsy in Open Cervical Cancer Surgery

OBJECTIVE

Multiple tracers have been used to improve lymphatic mapping and to reduce the false-negative rate of the sentinel node detection in gynecologic cancers. Nowadays, 99mTc colloids combined with blue-dye technique is the most extended technique. New alternatives such as the fluorescent indocyanine green and near-infrared fluorescent imaging detection have been introduced in lymphatic mapping staging procedures because of its easier visualization compared with the previous tracers.

METHODS

We used the laparoscopic infrared camera for the indocyanine green-guided sentinel node biopsy in a laparotomic radical hysterectomy in a pregnant patient after a cesarean section, with the aim of improving the detection rate of sentinel node biopsy in open surgery.

RESULTS

The technique was used in the first patient with accurate detection of sentinel node and no complications during the procedure.

CONCLUSIONS

The use of laparoscopic indocyanine green in open surgery may be a useful tool for the detection of sentinel node biopsy.

Sentinel Lymph Nodes Mapping in Cervical Cancer a Comprehensive Review

Objective

A comprehensive literature search for more recent studies pertaining to sentinel lymph node mapping in the surveillance of cervical cancer to assess if sentinel lymph node mapping has sensitivity and specificity for evaluation of the disease; assessment of posttreatment response and disease recurrence in cervical cancer.

Materials and Methods

The literature review has been constructed on a step wise study design that includes 5 major steps. This includes search for relevant publications in various available databases, application of inclusion and exclusion criteria for the selection of relevant publications, assessment of quality of the studies included, extraction of the relevant data and coherent synthesis of the data.

Results

The search yielded numerous studies pertaining to sentinel lymph node mapping, especially on the recent trends, comparison between various modalities and evaluation of the technique. Evaluation studies have appraised high sensitivity, high negative predictive values and low false-negative rate for metastasis detection using sentinel lymph node mapping. Comparative studies have established that of all the modalities for sentinel lymph node mapping, indocyanine green sentinel lymph node mapping has higher overall and bilateral detection rates. Corroboration of the deductions of these studies further establishes that the sentinel node detection rate and sensitivity are strongly correlated to the method or technique of mapping and the history of preoperative neoadjuvant chemotherapy.

Conclusions

The review takes us to the strong conclusion that sentinel lymph node mapping is an ideal technique for detection of sentinel lymph nodes in cervical cancer patients with excellent detection rates and high sensitivity. The review also takes us to the supposition that a routine clinical evaluation of sentinel lymph nodes is feasible and a real-time florescence mapping with indocyanine green dye gives better statistically significant overall and bilateral detection than methylene blue.

Can We Define the Risk of Lymph Node Metastasis in Early-Stage Cervical Cancer Patients? A Large-Scale, Retrospective Study

BACKGROUND

Sentinel lymph node (SLN) biopsy has emerged as one of the most appreciated techniques for reducing the rate of complete lymph node dissection (LND) performed in patients with early-stage cervical cancer (ECC). However, its performances are still a matter of debate and, to improve them, international guidelines recommend performing at least unilateral LND in case of SLN mapping. In a prior study, we identified a group of patients without evidence of lymph node metastasis (LNM). Our objective is to define a precise risk of LNM for each ECC patient in order to significantly tailor surgery for ECC.

METHODS

Clinical and pathological data of ECC patients were retrospectively collected by eight Italian institutions. Chi-square test or Fisher's exact test along with logistic regression analysis was used to determine the association of each variable between patients with or without LNM. Results of logistic regression have been used as a basis to calculate the probability to harboring LNM.

RESULTS

A total of 463 ECC patients were identified. No LNM was detected among the 161 (34.8%) patients who met the criteria and were defined as Very Low Risk. In the other 302 patients, the precise risk of LNM was calculated, and it was <1% in 31 (10.3%) patients.

CONCLUSIONS

Defining the precise risk of LNM could lead to proper selection of patients in whom any lymph nodal procedure, including SLN, could be avoided.

Indocyanine Green versus Radiotracer with or without Blue Dye for Sentinel Lymph Node Mapping in Stage >IB1 Cervical Cancer (>2 cm)

STUDY OBJECTIVE

To compare sentinel lymph node (SLN) mapping in women with cervical cancer stage >IB1 (tumor size >2 cm) using indocyanine green (ICG) versus the standard technique using radioisotope technetium 99m radiocolloid (Tc99^m) radiotracer with or without blue dye.

DESIGN

European multicenter, retrospective observational study (Canadian Task Force classification II-2).

SETTING

Four academic medical centers.

PATIENTS

Ninety-five women with stage IB1 cervical cancer (>2 cm) who underwent SLN mapping with Tc99^m with or without blue dye or ICG and radical hysterectomy.

INTERVENTION

The detection rate and bilateral mapping rate were compared between ICG and standard Tc99^m radiotracer with or without blue dye. Lymphadenectomy was performed, and the false-negative rate was assessed.

MEASUREMENTS AND MAIN RESULTS

Forty-seven patients underwent SLN mapping with Tc99^m with or without blue dye, and 48 did so with ICG. All patients underwent radical hysterectomy with or without bilateral salpingo-oophorectomy between 2008 and 2016. The overall detection rate of SLN mapping was 91.5% for Tc99^m with or without blue dye and 100% for ICG. A 91.7% rate of bilateral migration was achieved for ICG, significantly higher than the 66% obtained with Tc99^m with or without blue dye (p = .025). Nine of the 23 SLN-positive patients (39.1%) were diagnosed exclusively as a result of the ultrastaging used to identify micrometastases or isolated tumor cells only.

CONCLUSIONS

In advanced cervical cancer (stage IB1 >2 cm), the detection rate and bilateral migration rate on real-time fluorescent SLN mapping were higher with ICG than with Tc99^m radiotracer with or without blue dye. SLN mapping and ultrastaging can provide additional information for nodal staging in advanced cervical cancer. In this setting, ICG is a promising tool for mapping, appearing less affected by higher disease stage compared with traditional methods.

Value of Sentinel Lymph Node (SLN) Mapping and Biopsy using Combined Intracervical Radiotracers and Blue Dye Injections for Endometrial Cancer

Background:

Lymphadenectomy, as part of the initial surgical staging of patients with endometrial carcinoma, remains a controversial topic in gynecologic oncology. Sentinel lymph node (SLN) mapping has become a well-accepted procedure for melanomas and breast cancer; a number of investigators have begun to explore the utility and accuracy of this technique with regard to endometrial cancer.

Aim:

This study was conducted to evaluate SLN mapping of early stage endometrial cancer with blue dye in conjunction with a radioactive tracer.

Subjects and methods:

In this prospective cross-sectional study, patients with stage I and II endometrial cancer who were candidates for systemic lymph node dissection during surgery were enrolled, some underwent lymph node mapping and SLN biopsy using combined intra cervical radiotracer and blue dye injections and some applying only an intra cervical radiotracer. SLNs and other lymph nodes were sent for pathological assessment. Sensitivity, specificity, the positive predictive value, and the negative predictive value were calculated as predictive values for the radiotracer and blue dye.

Results:

Pre-operative lymph node mapping showed SLN in 29 out of 30 patients. Intra operations in 29/30 patients, SLNs were harvested by gamma probe; in 13 out of 19 patients SLNs were detected by blue dye. The median number of SLNs per patient was 3 and the total number of SLNs detected was 81. Four patients had positive pelvic lymph nodes. All of the positive nodes were SLNs. Using this technique (radiotracer and blue dye) an overall detection rate of 96.7%, an NPV of 100%, a sensitivity of 100% and a specificity of 3.85% were achieved.

Conclusion:

Results of SLN research for endometrial cancer are promising and make feasible the possibility of avoiding unnecessary aggressive surgical procedures in near future by advances in SLN mapping.

The detection of sentinel lymph nodes in laparoscopic surgery for uterine cervical cancer using 99m-technetium-tin colloid, indocyanine green, and blue dye

OBJECTIVE

Our objective was to determine the feasibility and detection rates and clarify the most effective combination of injected tracer types for sentinel lymph node (SLN) mapping in uterine cervical cancer in patients who have undergone laparoscopic surgery or neoadjuvant chemotherapy (NAC).

METHODS

A total of 119 patients with cervical cancer underwent SLN biopsy at radical hysterectomy using three types of tracers. The various factors related to side-specific detection rate, sensitivity, and false negative (FN) rate were analyzed.

RESULTS

The SLN detection rates using 99m-technetium ((99m)Tc)-tin colloid, indigo carmine, and indocyanine green (ICG) were 85.8%, 20.2%, and 61.6%, respectively. The patients with ≥2-cm-diameter tumors and those who received NAC had lower detection rates than those with <2-cm-diameter tumors (75.7% vs. 91.5%, p<0.01) and those who did not receive NAC (67.9% vs. 86.3%, p<0.01), respectively. Laparoscopic procedures had a higher detection rate than laparotomy (100.0% vs. 77.1%, p<0.01). No factors significantly affected the sensitivity; however, the patients with ≥2-cm-diameter tumors (86.0% vs. 1.4%, p<0.01), NAC (19.4% vs. 2.2%, p<0.01), and those who underwent laparotomy (7.4% vs. 0%, p<0.01) had an unfavorable FN rate.

CONCLUSION

Among the examined tracers, (99m)Tc had the highest detection of SLN mapping in patients with uterine cervical cancer. Patients with local advanced cervical cancer with/without NAC treatment might be unsuited for SLN mapping. SLN mapping is feasible and results in an excellent detection rate in patients with <2-cm-diameter cervical cancer. Laparoscopic surgery is the best procedure for SLN detection in patients with early-stage disease.

Fertility-sparing surgery for uterine cervical cancer

The standard treatment for early cervical cancer of the uterus (CC) is radical hysterectomy with resection of the parametrium and pelvic lymphadenectomy. At least 40% of patients develop early-stage CC during child-bearing age, therefore preserving the uterus to maintain fertility has been an important consideration. Several surgical procedures including conization and vaginal or abdominal radical trachelectomy have been reported. These procedures are safe for removing lymph node negative CC tumors with <2 cm diameter. Recently, less radical surgical procedures that maintain fertility, such as conization, simple trachelectomy, minimally invasive surgery and neoadjuvant chemotherapy, have been indicated for tumors greater than 2 cm in diameter. In this review, we discuss the currently accepted surgical approaches for treating CC while maintaining fertility.

Lymphatic mapping and sentinel node biopsy in ovarian tumors: a study using intra-operative Tc-99m-Phytate and lymphoscintigraphy imaging

Background

Experience on sentinel node mapping in ovarian tumors is very limited. We evaluated the sentinel node concept in ovarian tumors using intra-operativeTc-99m-Phytate injection and lymphoscintigraphy imaging.

Methods

Thirty-five patients with a pelvic mass due to an ovarian pathology were included in the study. The radiotracer was injected just after laparotomy and before removal of the tumor either beneath the normal cortex (10 patients) or in the utero-ovarian and suspensory ligaments of the ovary just beneath the peritoneum two injections of the radiotracer (25 patients). For malignant masses, the sentinel nodes were identified using a hand held gamma probe. Then standard pelvic and para-aortic lymphadenectomy was performed. In case of benign pathologies or borderline ovarian tumors on frozen section, lymphadenectomy was not performed. The morning after surgery, all patients were sent for lymphoscintigraphy imaging of the abdomen and pelvis.

Results

Sentinel node was identified only in 4 patients of the cortical injection group. At least one sentinel node could be identified in 21 patients of the sub-peritoneal group. Sentinel nodes were identified only in the para-aortic area in 21, pelvic/para-aortic areas in 2, and pelvic only area in 2 patients. Three patients had lymph node involvement and all had involved sentinel nodes (no false negative case).

Conclusion

Sentinel node mapping using intra-operative injection of the radiotracer (in the utero-ovarian and suspensory ligaments of the ovary just beneath the peritoneum) is feasible in ovarian tumors. Technical aspects of this method should be explored in larger multicenter studies in the future.

Sentinel lymph node detection rates using indocyanine green in women with early-stage cervical cancer

OBJECTIVE

Our study objective was to determine feasibility and mapping rates using indocyanine green (ICG) for sentinel lymph node (SLN) mapping in early-stage cervical cancer.

METHODS

We performed a retrospective review of all women who underwent SLN mapping with ICG during primary surgical management of early-stage cervical cancer by robotic-assisted radical hysterectomy (RA-RH) or fertility-sparing surgery. Patients were treated at two high-volume centers from 10/2012 to 02/2016. Completion pelvic lymphadenectomy was performed after SLN biopsy; additionally, removal of clinically enlarged/suspicious nodes was part of the SLN treatment algorithm.

RESULTS

Thirty women with a median age of 42.5 and BMI of 26.5 were included. Most (90%) had stage IB disease, and 67% had squamous histology. RA-RH was performed in 86.7% of cases. One patient underwent fertility-sparing surgery. Median cervical tumor size was 2.0cm. At least one SLN was detected in all cases (100%), with bilateral mapping achieved in 87%. SLN detection was not impacted by tumor size and was most commonly identified in the hypogastric (40.3%), obturator (26.0%), and external iliac (20.8%) regions. Five cases of lymphatic metastasis were identified (16.7%): three in clinically enlarged SLNs, one in a clinically enlarged non-SLN, and one case with cytokeratin positive cells in an SLN. All metastatic disease would have been detected even if full lymphadenectomy had been omitted from our treatment algorithm, CONCLUSIONS: SLN mapping with ICG is feasible and results in high detection rates in women with early-stage cervical cancer. Prospective studies are needed to determine if SLN mapping can replace lymphadenectomy in this setting.

Cervical cancer: what's new?

Cervical cancer is the most common gynecological cancer in Brazil. Among women, it is the second most frequent, second only to breast cancer. It is the fourth leading cause of cancer death in the country, with estimated 15,590 new cases (2014) and 5,430 deaths (2013). In order to update information to improve outcomes, reduce morbidity and optimize the treatment of this cancer, this article will address the advancement of knowledge on cervical cancer. The topics covered include the role of surgery in different stages, treatment of locally advanced carcinomas, fertility preservation, the role of the sentinel lymph node technique, indications and techniques of radiotherapy and chemotherapy, and some special situations.

The sentinel node approach in gynaecological malignancies

This review discusses the state-of-the-art of sentinel lymph node mapping in gynaecological malignancies, including cervical cancer, endometrial cancer, and vulvar cancer, with an emphasis on new technological advances. For this objective, PubMed/MEDLINE was searched for relevant studies about the sentinel lymph node procedure in gynaecology. In particular, the use of preoperative lymphatic mapping with lymphoscintigraphy and single photon emission tomography/computed tomography (SPECT/CT) was identified in 18 studies. Other recent advances as hybrid tracers (e.g. ICG-^99mTc-nanocolloid) and intraoperative tools (portable γ-camera and 3D navigation devices) appear to also represent a useful guide for the surgeon during the operation. Concerning vulvar and cervical cancers, the sentinel lymph node procedure has been incorporated to the current guidelines in Europe and North America, whereas for endometrial cancer it is considered investigative.

Beyond sentinel node algorithm. Toward a more tailored surgery for cervical cancer patients

Nowadays cervical cancer is frequently diagnosed at early stage. For these patients lymph node metastasis (LNM) is considered the most important prognostic factor. During the last decade many efforts have been made to reduce rate of complications associated with lymphadenectomy (LND). A great interest has arisen in sentinel lymph node (SLN) biopsy as a technique able to decrease number of LND performed and, at the same time, to assess lymph nodal status. High diagnostic performances have been reached thanks to SLN surgical algorithm. However, despite the efforts, about 25% of these patients undergo at least unilateral LND to meet NCCN recommendations. Data of women with International Federation of Gynecology and Obstetrics stage IA1‐IB1/IIA1 cervical carcinoma were retrospectively collected by six Italian institutions. All patients underwent complete preoperative staging workup and were primarily treated by radical hysterectomy and pelvic bilateral LND. A total of 368 patients with early‐stage cervical cancer were identified. Among them 333 (90.5%) showed no suspicious enlarged nodes at the preoperative magnetic resonance imaging (MRI). In this subset, tumor diameter ≥20 mm was the only independent predictor of LN status (P = 0.003). None of the 106 patients with negative MRI nodal assessment, with squamous and adenosquamous histotype and a tumor diameter less than 2 cm had LNM. Based on these results we propose a new modified SLN surgical algorithm that could safely reduce LND performed in patients with very low‐risk early‐stage cervical cancer.

From Conventional Radiotracer Tc-99(m) with Blue Dye to Indocyanine Green Fluorescence: A Comparison of Methods Towards Optimization of Sentinel Lymph Node Mapping in Early Stage Cervical Cancer for a Laparoscopic Approach

BACKGROUND

The credibility of sentinel lymph node (SLN) mapping is becoming increasingly more established in cervical cancer. We aimed to assess the sensitivity of SLN biopsy in terms of detection rate and bilateral mapping in women with cervical cancer by comparing technetium-99 radiocolloid (Tc-99(m)) and blue dye (BD) versus fluorescence mapping with indocyanine green (ICG).

METHODS

Data of patients with cervical cancer stage 1A2 to 1B1 from 5 European institutions were retrospectively reviewed. All centers used a laparoscopic approach with the same intracervical dye injection. Detection rate and bilateral mapping of ICG were compared, respectively, with results obtained by standard Tc-99(m) with BD.

RESULTS

Overall, 76 (53 %) of 144 of women underwent preoperative SLN mapping with radiotracer and intraoperative BD, whereas 68 of (47 %) 144 patients underwent mapping using intraoperative ICG. The detection rate of SLN mapping was 96 % and 100 % for Tc-99(m) with BD and ICG, respectively. Bilateral mapping was achieved in 98.5 % for ICG and 76.3 % for Tc-99(m) with BD; this difference was statistically significant (p < 0.0001).

CONCLUSIONS

The fluorescence SLN mapping with ICG achieved a significantly higher detection rate and bilateral mapping compared to standard radiocolloid and BD technique in women with early stage cervical cancer. Nodal staging with an intracervical injection of ICG is accurate, safe, and reproducible in patients with cervical cancer. Before replacing lymphadenectomy completely, the additional value of fluorescence SLN mapping on both perioperative morbidity and survival should be explored and confirmed by ongoing controlled trials.

Evaluation of sentinel lymph nodes in vulvar, endometrial and cervical cancers

Sentinel lymph node (SLN) biopsies are a sensitive tool in evaluating lymph nodes for multiple cancers, and in some diseases they decrease morbidity in both the short- and long-term. SLN detection in gynecologic malignancies has been studied extensively over the past decade. We review the current literature on SLN dissection in vulvar, endometrial and cervical cancers. Large, well-designed trials in each of the three types of cancer have demonstrated high sensitivity and low false-negative rates when SLN biopsy is performed in the correct patients and with an appropriate technical approach. In all of these cases the addition of ultra-staging to conventional pathology yields increased detection of micrometastatic disease. Biopsy of the sentinel nodes is feasible and safe in early vulvar malignancies, with multiple studies describing low recurrence rates in those women who have with negative SLNs. There does not appear to be a survival benefit to lymphadenectomy over SLN biopsy and quality of life is improved in women undergoing SLN biopsy. Optimal treatment strategies for women with positive nodal biopsies, particularly in cases with micrometastatic disease, remain unclear. Multiple large studies investigating the utility of SLN biopsy in endometrial malignancy have found that sentinel nodal status is a reliable predictor of metastases in women with low-risk disease. Prospective studies are ongoing and suggest sentinel nodal detection may soon become widely accepted as an alternative standard of care for select cases of endometrial cancer. In cervical cancer, SLN biopsy is accurate for diagnosing metastatic disease in early stage tumors (≤ 2 cm diameter or stage ≤ IB2) where the risk of metastasis is low. It is unknown if women who undergo SLN biopsy alone will have different survival outcomes than women who undergo complete lymphadenectomy in these cases. In a specific population of women with vulvar cancer, SLN dissection is an effective and safe alternative to complete dissection. It can be offered as an alternative management strategy in these women. In women who do undergo SLN biopsy, it is associated with improved quality of life. Promising evidence supporting the utility of SLN dissection in endometrial and cervical cancer continues to emerge, and it may soon become a reasonable option for select patients. However, continued research and refinement of appropriate patient selection and long-term follow-up are necessary.

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.

Symptomatic Lymphocele Formation After Sentinel Lymph Node Biopsy for Early Stage Cervical Cancer

In early stage cervical cancer, nodal status is the most important prognostic factor, and execution of retroperitoneal lymphadenectomy is currently an integral part of surgical therapy. Sentinel lymph node biopsy has been progressively incorporated with surgical therapy and could reduce morbidity. However, the current incidence of complications exclusively related to the procedure is unknown. We report on a 29-year-old woman affected by cervical cancer (Fédération Internationale de Gynécologie et d'Obstétrique Stage 1b1), who underwent sentinel lymph node biopsy in combination with radical vaginal trachelectomy, and who later developed a symptomatic pelvic lymphocele that required surgical therapy. Conservative procedures in the pelvic lymph nodes are not free of complications, especially with regard to the formation of symptomatic lymphoceles. This report brings to light an important discussion about the exact magnitude of the complications associated with the procedure.

Advances in research of fluorescence imaging for detection of gastrointestinal tumors

Fluorescence imaging, which has a high sensitivity, produces images by capturing fluorescence signal from the inside of organisms. Over the past few years, notable development of fluorescence imaging technique has been made in the field of gastrointestinal cancer. Imaging instruments and fluorescent probes for fluorescence imaging are being improved and innovated, making it a promising technique for broad clinical applications in the near future. Future clinical applications of fluorescence imaging include aiding diagnosis and surgical treatment of gastrointestinal tumors, which are important development directions of this technique. However, increasing the safety and the accuracy for tumor detection is a challenge for fluorescence imaging. Besides, in order to acquire better diagnostic effects, the combination of fluorescence imaging and other imaging modalities which require novel imaging probes for tumor is also an important trend for fluorescence imaging development.