Interstitial CT lymphography-guided localization of breast sentinel lymph node: preliminary results

Top 100 cited classical articles in sentinel lymph nodes biopsy for breast cancer

Background

The sentinel lymph node biopsy (SLNB) takes on a critical significance in breast cancer surgery since it is the gold standard for assessing axillary lymph node (ALN) metastasis and determining whether to perform axillary lymph node dissection (ALND). A bibliometric analysis is beneficial to visualize characteristics and hotspots in the field of sentinel lymph nodes (SLNs), and it is conducive to summarizing the important themes in the field to provide more insights into SLNs and facilitate the management of SLNs.

Materials and methods

Search terms relating to SLNs were aggregated and searched in the Web of Science core collection database to identify the top 100 most cited articles. Bibliometric tools were employed to identify and analyze publications for annual article volume, authors, countries, institutions, keywords, as well as hotspot topics.

Results

The period was from 1998 to 2018. The total number of citations ranged from 160 to 1925. LANCET ONCOLOGY and JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION were the top two journals in which the above articles were published. Giuliano, AE was the author with the highest number of articles in this field with 15. EUROPEAN INST ONCOL is the institution with the highest number of publications, with 35 articles. Hotspots include the following 4 topics, false-negative SLNs after neoadjuvant chemotherapy; prediction of metastatic SLNs; quality of life and postoperative complications; and lymphography of SLNs.

Conclusion

This study applies bibliometric tools to analyze the most influential literature, the top 100 cited articles in the field of SLNB, to provide researchers and physicians with research priorities and hotspots.

Contrast enhanced computed tomography assessment of superficial inguinal lymph node metastasis in canine mammary gland tumors

Mammary gland neoplasms are predominant in dogs. However, sentinel lymph node (SLN) status assessment criteria have not been established for these cases. In this retrospective, secondary analysis, diagnostic case control study, CT images of 65 superficial inguinal SLNs were obtained before and 1, 3, 5, and 10 min after intravenous administration of contrast agent (iopamidol 370 mgI/mL). The presence and degree of postcontrast enhancement were assessed, by means of the median absolute density value and the maximum absolute density value at any time point in the center and in the periphery of each SLN measured in Hounsfield units (HU), before and after contrast agent administration. These values were compared with histopathological findings postsurgical excision. Receiver operating characteristic analysis was conducted. The absolute density values ranged widely at each time point and within each group of nodes (negative, positive, control group). At all time points, the median density value in the center and in the periphery was significantly higher in metastatic than in non-metastatic SLNs (P ≤ .014). Among the parameters tested, the median absolute density value measured in the periphery of the SLN 3 min after injection showed the highest sensitivity, specificity, and accuracy (AUC) (87.5%, 82.1%, and 92.1% respectively), with a cutoff value of 50.9 HU. The maximum absolute density value at any time point in the center and periphery of the SLNs was also significantly higher in metastatic SLNs compared to non-metastatic (P ≤ .001). With a cutoff value of 59.5 HU, the maximum absolute density value in the periphery of the SLN displayed high sensitivity and specificity (87.5% and 89.3%, respectively). The results of this study support the hypothesis that contrast enhanced CT imaging may aid in the assessment of SLN metastasis in dogs with mammary gland neoplasms.

Sentinel lymph node biopsy in breast cancer guided by CT lymphography; History, evolution and current applications

Sentinel lymph node biopsy (SLNB) has efficiently replaced axillary lymph node dissection (ALND) in axillary staging in node-negative breast cancer patients. Dual sentinel lymph node (SLN) localization using radioisotopes and blue dye is the standard technique for SLN mapping. Yet, nuclear medicine facilities are not widely available worldwide. In Japan, Computed tomography lymphography (CTLG) is presented as an SLN mapping technique which was first suggested in 2003 by Suga et al. Multiple subsequent studies confirmed the efficacy of CTLG in SLN mapping in breast cancer. Further applications of the technique followed; such as prediction of SLN metastasis using CTLG, the use of CTLG guided SLN biopsy after neoadjuvant therapy, video-assisted CTLG guided SLN biopsy, the use of real-time virtual sonography with 3-D CTLG, and preoperative localization of the CTLG mapped SLN using either real-time virtual sonography (RVS) guided Indocyanine green (ICG) injection or its marking using liquid charcoal and silver wire and the use of SPIO enhanced magnetic resonance imaging (MRI) for prediction of metastasis in SLNs detected by CTLG. This efficacy and variable applications open the door for conducting wide-scale randomized controlled trials to suggest using CTLG as an efficient alternative for the use of radioisotopes in SLN mapping in breast cancer patients, especially in low and middle-income countries.

New Developments in Imaging for Sentinel Lymph Node Biopsy in Early-Stage Oral Cavity Squamous Cell Carcinoma

Sentinel lymph node biopsy (SLNB) is a diagnostic staging procedure that aims to identify the first draining lymph node(s) from the primary tumor, the sentinel lymph nodes (SLN), as their histopathological status reflects the histopathological status of the rest of the nodal basin. The routine SLNB procedure consists of peritumoral injections with a technetium-99m [^99mTc]-labelled radiotracer followed by lymphoscintigraphy and SPECT-CT imaging. Based on these imaging results, the identified SLNs are marked for surgical extirpation and are subjected to histopathological assessment. The routine SLNB procedure has proven to reliably stage the clinically negative neck in early-stage oral squamous cell carcinoma (OSCC). However, an infamous limitation arises in situations where SLNs are located in close vicinity of the tracer injection site. In these cases, the hotspot of the injection site can hide adjacent SLNs and hamper the discrimination between tracer injection site and SLNs (shine-through phenomenon). Therefore, technical developments are needed to bring the diagnostic accuracy of SLNB for early-stage OSCC to a higher level. This review evaluates novel SLNB imaging techniques for early-stage OSCC: MR lymphography, CT lymphography, PET lymphoscintigraphy and contrast-enhanced lymphosonography. Furthermore, their reported diagnostic accuracy is described and their relative merits, disadvantages and potential applications are outlined.

Development and Themes of Diagnostic and Treatment Procedures for Secondary Leg Lymphedema in Patients with Gynecologic Cancers

Patients with leg lymphedema sometimes suffer under constraint feeling leg heaviness and pain, requiring lifelong treatment and psychosocial support after surgeries or radiation therapies for gynecologic cancers. We herein review the current issues (a review of the relevant literature) associated with recently developed diagnostic procedures and treatments for secondary leg lymphedema, and discuss how to better manage leg lymphedema. Among the currently available diagnostic tools, indocyanine green lymphography (ICG-LG) can detect dermal lymph backflow in asymptomatic legs at stage 0. Therefore, ICG-LG is considered the most sensitive and useful tool. At symptomatic stage ≥1, ultrasonography, magnetic resonance imaging-lymphography/computed tomography-lymphography (MRI-LG/CT-LG) and lymphosintiography are also useful. For the treatment of lymphedema, complex decongestive physiotherapy (CDP) including manual lymphatic drainage (MLD), compression therapy, exercise and skin care, is generally performed. In recent years, CDP has often required effective multi-layer lymph edema bandaging (MLLB) or advanced pneumatic compression devices (APCDs). If CDP is not effective, microsurgical procedures can be performed. At stage 1–2, when lymphaticovenous anastomosis (LVA) is performed, lymphaticovenous side-to-side anastomosis (LVSEA) is principally recommended. At stage 2–3, vascularized lymph node transfer (VLNT) is useful. These ingenious procedures can help maintain the patient’s quality of life (QOL) but unfortunately cannot cure lymphedema. The most important concern is the prevention of secondary lymphedema, which is achieved through approaches such as skin care, weight control, gentle limb exercises, avoiding sun and heat, and elevation of the affected leg.

Anatomical classification of breast sentinel lymph nodes using computed tomography-lymphography

To evaluate the anatomical classification and location of breast sentinel lymph nodes, preoperative computed tomography–lymphography examinations were retrospectively reviewed for sentinel lymph nodes in 464 cases clinically diagnosed with node-negative breast cancer between July 2007 and June 2016. Anatomical classification was performed based on the numbers of lymphatic routes and sentinel lymph nodes, the flow direction of lymphatic routes, and the location of sentinel lymph nodes. Of the 464 cases reviewed, anatomical classification could be performed in 434 (93.5 %). The largest number of cases showed single route/single sentinel lymph node (n = 296, 68.2 %), followed by multiple routes/multiple sentinel lymph nodes (n = 59, 13.6 %), single route/multiple sentinel lymph nodes (n = 53, 12.2 %), and multiple routes/single sentinel lymph node (n = 26, 6.0 %). Classification based on the flow direction of lymphatic routes showed that 429 cases (98.8 %) had outward flow on the superficial fascia toward axillary lymph nodes, whereas classification based on the height of sentinel lymph nodes showed that 323 cases (74.4 %) belonged to the upper pectoral group of axillary lymph nodes. There was wide variation in the number of lymphatic routes and their branching patterns and in the number, location, and direction of flow of sentinel lymph nodes. It is clinically very important to preoperatively understand the anatomical morphology of lymphatic routes and sentinel lymph nodes for optimal treatment of breast cancer, and computed tomography–lymphography is suitable for this purpose.

Multimodal photoacoustic imaging as a tool for sentinel lymph node identification and biopsy guidance

As a minimally invasive method, sentinel lymph node biopsy (SLNB) in conjunction with guidance methods is the standard method to determine cancer metastasis in breast. The desired guidance methods for SLNB should be capable of precise SLN localization for accurate diagnosis of micro-metastases at an early stage of cancer progression and thus facilitate reducing the number of SLN biopsies for minimal surgical complications. For this, high sensitivity to the administered dyes, high spatial and contrast resolutions, deep imaging depth, and real-time imaging capability are pivotal requirements. Currently, various methods have been used for SLNB guidance, each with their own advantages and disadvantages, but no methods meet the requirements. In this review, we discuss the conventional SLNB guidance methods in this perspective. In addition, we focus on the role of the PA imaging modality on real-time SLN identification and biopsy guidance. In particular, PA-based hybrid imaging methods for precise SLN identification and efficient biopsy guidance are introduced, and their unique features, advantages, and disadvantages are discussed.

[Imaging diagnostic methods for identification of sentinel lymph nodes in patients with early squamous cell carcinoma of the oral cavity mucosa: a literature review]

The paper describes properties of clinical visualization approaches which are applied for detection of sentinel lymph nodes in patients suffering from oral cavity squamous cell cancer. Diagnostic efficiency results and technological features of different imaging techniques are discussed.

Superparamagnetic iron oxide-enhanced MRI at 3 T for accurate axillary staging in breast cancer

BACKGROUND

The aim of this study was to evaluate whether MRI at 3 T with superparamagnetic iron oxide (SPIO) enhancement is an accurate and useful method for detecting metastases in sentinel nodes identified by CT-lymphography (CT-LG) in patients with breast cancer. The results were compared with those obtained using CT-LG alone and diagnosing metastasis according to size criteria.

METHODS

Patients with clinically node-negative breast cancer were included. Sentinel nodes identified by CT-LG were evaluated prospectively using SPIO-enhanced MRI at 3 T. Sentinel node size was measured on CT-LG, and a node larger than 5 mm in short-axis diameter was considered metastatic. Sentinel nodes localized by CT-LG were removed, and imaging results and histopathological findings were compared.

RESULTS

Sentinel nodes were identified successfully by CT-LG in 69 (99 per cent) of 70 patients. All 19 patients with a finding of metastasis in sentinel nodes at pathology were also shown to have metastases on MRI. Forty-eight of 50 patients with non-metastatic sentinel nodes diagnosed at pathology were classified as having non-metastatic nodes on MRI. On a patient-by-patient basis, the sensitivity, specificity and accuracy of MRI for the diagnosis of sentinel node metastases were 100, 96 and 97 per cent; respective values for CT-LG were 79, 56 and 62 per cent. The specificity and accuracy of MRI were superior to those of CT-LG (P < 0·001 and P = 0·002 respectively).

CONCLUSION

SPIO-enhanced MRI at 3 T is useful for accurate diagnosis of metastatic sentinel nodes, indicating that sentinel node biopsy may be avoided in patients with breast cancer who have non-metastatic sentinel nodes on imaging.

Sentinel lymph node biopsy using computed tomographic lymphography in patients with early tongue cancer

Conclusions: Because computed tomography (CT) lymphography provides preoperative images of anatomic relationships between a tumor, its associated lymph vessels, and the sentinel lymph node (SLN), it may aid in directing the SLN biopsy for management of early tongue cancer. Objectives: SLN biopsy using a radioisotope (RI) generally has been performed in head and neck cancer. However, this method can be performed only at institutions that are licenced for its use. In this study, we evaluated the utility of performing SLN biopsy in patients with early tongue cancer using the newly developed technique of CT lymphography. Methods: Enrolled in this study were 31 patients with T1N0 or T2N0 tongue cancer. CT images were obtained before and after injection of iopamidol into the peritumoral region and the SLN was identified as the first enhanced lymph node. SLN biopsy was performed using CT lymphographic guidance combined with blue dye injection. Results: The SLN was detected by CT lymphography in 28 cases (90.3%). By intraoperative frozen section examination, metastases to SLNs were found in 4 (14.3%) (T1N0, 1 patient; T2N0, 3 patients) of the 28 patients. Of these four, SLN micrometastases were found in one patient.

Preoperative diagnosis of sentinel lymph node (SLN) metastasis using 3D CT lymphography (CTLG)

BACKGROUND

Sentinel lymph node biopsy (SLNB) became a standard procedure for patients with early breast cancer, however, an indication of SLN navigation to metastatic disease may lead to misdiagnosis for staging. Preoperative CTLG with a water-soluble iodinated contrast medium visualizes the correct primary SLNs and its afferent lymphatic channels surrounding detailed anatomy, therefore it can predict LN metastasis by visualizing the lymph vessel obstruction or stain defect of the SLN by tumor. The current study presents the value of CTLG for preoperative prediction for SLN status.

METHODS

A total of 228 patients with Tis-T2 breast cancer who did not receive primary chemotherapy were studied. SLN metastasis was diagnosed according to the following staining patterns of SLNs and afferent lymphatic vessels: stain defect of SLN, obstruction, stagnation, dilation, and detour of the lymphatic vessels by tumor occupation. The diagnosis was compared with the pathological results to evaluate the accuracy of prediction for SLN metastasis using CTLG.

RESULTS

Twenty-seven of 228 patients had metastatic SLN pathologically. Twenty-five of these were diagnosed as metastatic preoperatively. The accuracy for metastatic diagnosis using CTLG was 89.0%, sensitivity was 92.6%, and specificity was 88.6%. The positive predictive value was 52.1% and negative predictive value was 98.8%.

CONCLUSION

CTLG can select the candidate with truly node negative cases in early breast cancer patients, because it predicts lymph node metastasis preoperatively from natural status of the lymphographic image. It also might omit the SLN biopsy itself.

Current and future lymphatic imaging modalities for tumor staging

Tumor progression is supported by the lymphatic system which should be scanned efficiently for tumor staging as well as the enhanced therapeutic outcomes. Poor resolution and low sensitivity is a limitation of traditional lymphatic imaging modalities; thus new noninvasive approaches like nanocarriers, magnetic resonance imaging, positron-emission tomography, and quantum dots are advantageous. Some newer modalities, which are under development, and their potential uses will also be discussed in this review.

Emerging lymphatic imaging technologies for mouse and man

The lymphatic circulatory system has diverse functions in lipid absorption, fluid homeostasis, and immune surveillance and responds dynamically when presented with infection, inflammation, altered hemodynamics, and cancer. Visualization of these dynamic processes in human disease and animal models of disease is key to understanding the contributory role of the lymphatic circulatory system in disease and to devising effective therapeutic strategies. Longitudinal, non-destructive, and repeated imaging is necessary to expand our understanding of disease progression and regression in basic science and clinical investigations. Herein we summarize recent advances in in vivo lymphatic imaging employing magnetic resonance, computed tomography, lymphoscintigraphy, and emerging optical techniques with respect to their contributory roles in both basic science and clinical research investigations.

Sentinel node mapping of VX2 carcinoma in rabbit thigh with CT lymphography using ethiodized oil

OBJECTIVE

To assess the feasibility of computed tomography (CT) lymphography using ethiodized oil for sentinel node mapping in experimentally induced VX2 carcinoma in the rabbit thigh.

MATERIALS AND METHODS

This experiment received approval from the institutional animal use and care administrative advisory committee. Twenty-three rabbits with VX2 carcinoma in the thigh underwent CT before and after (1 hour, 2 hour) peritumoral injection of 2 mL ethiodized oil. After the CT examination, sentinel nodes were identified by peritumoral injection of methylene blue and subsequently removed. The retrieved sentinel and non-sentinel lymph nodes were investigated with radiographic and pathologic examinations. Based on the comparison of CT findings with those of radiographic and pathologic examinations, the diagnostic performance of CT for sentinel node identification was assessed.

RESULTS

All 23 rabbits showed 53 ethiodized oil retention nodes on post-injection CT and specimen radiography, and 52 methylene blue-stained nodes at the right femoroiliac area. Of the 52 blue-stained sentinel nodes, 50 nodes demonstrated ethiodized oil retention. Thus, the sentinel node detection rate of CT was 96% (50 of 52). On pathologic examination, 28 sentinel nodes in 17 rabbits (nodes/rabbit, mean ± standard deviation, 1.7 ± 0.6) harbored metastasis. Twenty seven of the 28 metastatic sentinel nodes were found to have ethiodized oil retention.

CONCLUSION

Computed tomography lymphography using ethiodized oil may be feasible for sentinel node mapping in experimentally induced VX2 carcinoma in the rabbit thigh.

Sentinel nodes identified by computed tomography-lymphography accurately stage the axilla in patients with breast cancer

BACKGROUND

Sentinel node biopsy often results in the identification and removal of multiple nodes as sentinel nodes, although most of these nodes could be non-sentinel nodes. This study investigated whether computed tomography-lymphography (CT-LG) can distinguish sentinel nodes from non-sentinel nodes and whether sentinel nodes identified by CT-LG can accurately stage the axilla in patients with breast cancer.

METHODS

This study included 184 patients with breast cancer and clinically negative nodes. Contrast agent was injected interstitially. The location of sentinel nodes was marked on the skin surface using a CT laser light navigator system. Lymph nodes located just under the marks were first removed as sentinel nodes. Then, all dyed nodes or all hot nodes were removed.

RESULTS

The mean number of sentinel nodes identified by CT-LG was significantly lower than that of dyed and/or hot nodes removed (1.1 vs 1.8, p <0.0001). Twenty-three (12.5%) patients had ≥2 sentinel nodes identified by CT-LG removed, whereas 94 (51.1%) of patients had ≥2 dyed and/or hot nodes removed (p <0.0001). Pathological evaluation demonstrated that 47 (25.5%) of 184 patients had metastasis to at least one node. All 47 patients demonstrated metastases to at least one of the sentinel nodes identified by CT-LG.

CONCLUSIONS

CT-LG can distinguish sentinel nodes from non-sentinel nodes, and sentinel nodes identified by CT-LG can accurately stage the axilla in patients with breast cancer. Successful identification of sentinel nodes using CT-LG may facilitate image-based diagnosis of metastasis, possibly leading to the omission of sentinel node biopsy.

Computed tomographic lymphography for sentinel lymph node biopsy in male breast cancer: report of two cases

Male breast cancer is rare, accounting for less than 1% of breast cancers. Because of its rarity evidence of the usefulness sentinel lymph node biopsy (SLNB) for male breast cancer has not been established. Moreover, a navigation system which can easily determine the incision site of SLNB is needed because a second incision for SLNB is necessary in most cases. We report successful computed tomographic lymphography (CTLG)-guided SLNB in two male breast cancer cases: the first patient was a 79-year-old man and the second was a 64-year-old man. Both had presented with a lump behind the nipple. Clinical diagnoses were early breast carcinoma in both cases. The second patient took tamoxifen 20 mg daily as neoadjuvant endocrine therapy. SLNs were clearly visualized by CTLG, allowing mastectomies with SLNB to be performed. Both SLNB were negative, such that axillary lymph node dissection was not needed. Preoperative CTLG is useful for visualizing lymph flow and detecting SLN in male breast cancer.

Early gastric cancer: feasibility of CT lymphography with ethiodized oil for sentinel node mapping

PURPOSE

To evaluate the feasibility of CT lymphography with ethiodized oil for sentinel node mapping in porcine stomachs and in patients with early gastric cancer.

MATERIALS AND METHODS

Approval for the animal study was obtained from the authors' institutional animal use and care administrative advisory committee, the clinical study was approved by the institutional review board, and informed consent was obtained from each participant. Five pigs underwent CT lymphography 1 hour after gastric subserosal injection of 1 mL ethiodized oil and sentinel node mapping with injection of 1 mL methylene blue. Ethiodized oil retention nodes were identified on the radiographic images of the gastric specimen and removed for histopathologic examination. In addition, 10 patients with early gastric cancer underwent CT lymphography with peritumoral injection of 1 mL ethiodized oil, followed by sentinel basin extirpation with CT and routine nodal dissection. The removed sentinel basins were examined by radiography. Histopathologic examination was performed for dissected nodes, including sentinel nodes.

RESULTS

In each of the five pigs, CT showed one perigastric ethiodized oil retention node. After harvesting the ethiodized oil retention node, blue-stained areas were identified in the five removed nodes and intranodal ethiodized oil was detected on histopathologic examination. In all 10 patients, CT lymphography with ethiodized oil successfully defined the sentinel basin with ethiodized oil retention nodes. CT lymphography revealed 20 ethiodized oil retention nodes. After basin extirpation, 28 and 46 nodes were detected on radiographic and histopathologic examinations. Histopathologic examination revealed that one patient had micrometastases at two sentinel nodes and another patient had isolated tumor cells at one sentinel node. No patient had metastasis in nonsentinel nodes.

CONCLUSION

CT lymphography with ethiodized oil may be a feasible method for sentinel node mapping in patients with early gastric cancer.

The lingual lymph node identified as a sentinel node on CT lymphography in a patient with cN0 squamous cell carcinoma of the tongue

We performed CT lymphography on an 81-year-old female patient with a histologically confirmed squamous cell carcinoma of the tongue with no clinical or radiological evidence of cervical lymph node involvement. The lateral lingual lymph node was identified as a sentinel node, which is the first lymph node to receive drainage from a primary tumour. CT lymphography also showed draining lymphatics passing through the sublingual space, the medial side of the submandibular gland and near the hyoid bone and connected with the middle internal jugular node. Although metastasis to the lateral lingual lymph node is known as one of the crucial events in determining survival outcome in cancer of the tongue and floor of the mouth, very few reports are available on the imaging of the lateral lingual lymph node metastasis. This is the first report regarding the lateral lingual lymph node identified as a sentinel node demonstrated on CT lymphography.

Preclinical lymphatic imaging

Noninvasive in vivo imaging of lymphatic vessels and lymphatic nodes is expected to fulfill the purpose of analyzing lymphatic vessels and their function, understanding molecular mechanisms of lymphangiogenesis and lymphatic spread of tumors, and utilizing lymphatic molecular markers as a prognostic or diagnostic indicator. In this review, we provide a comprehensive summary of in vivo imaging modalities for detecting lymphatic vessels, lymphatic drainage, and lymphatic nodes, which include conventional lymphatic imaging techniques such as dyes and radionuclide scintigraphy as well as novel techniques for lymphatic imaging such as optical imaging, computed tomography, magnetic resonance imaging, ultrasound, positron emission tomography using lymphatic biomarkers, photoacoustic imaging, and combinations of multiple modalities. The field of lymphatic imaging is ever evolving, and technological advances, combined with the development of new contrast agents, continue to improve the research of lymphatic vascular system in health and disease states as well as to improve the accuracy of diagnosis in the relevant diseases.

Advances in lymphatic imaging and drug delivery

Cancer remains the second leading cause of death after heart disease in the US. While metastasized cancers such as breast, prostate, and colon are incurable, before their distant spread, these diseases have invaded the lymphatic system as a first step in their progression. Hence, proper evaluation of the disease state of the lymphatics which drain a tumor site is crucial to staging and the formation of a treatment plan. Current lymphatic imaging modalities with visible dyes and radionucleotide tracers offer limited sensitivity and poor resolution; however, newer tools using nanocarriers, quantum dots, and magnetic resonance imaging promise to vastly improve the staging of lymphatic spread without needless biopsies. Concurrent with the improvement of lymphatic imaging agents, has been the development of drug carriers that can localize chemotherapy to the lymphatic system, thus improving the treatment of localized disease while minimizing the exposure of healthy organs to cytotoxic drugs. This review will focus on the use of various nanoparticulate and polymeric systems that have been developed for imaging and drug delivery to the lymph system, how these new devices improve upon current technologies, and where further improvement is needed.

High rate of solitary sentinel node metastases identification by fluorescence-guided lymphatic imaging in breast cancer

BACKGROUND

The lymph node status was shown to be an important prognostic factor for breast cancer, but controversial issues remain. There has been increased focus on optimizing the visualization of lymph nodes for an accurate and selective approach to axillary lymph nodes. Fluorescence-guided lymphatic imaging is a potential candidate for further research on remaining controversies.

METHODS

Forty-seven patients were subject to injection of indocyanine green for navigation to the SLN based on fluorescent dye retention detection. In two groups, patients either received intended axillary lymph node dissection (ALND) and sentinel lymph node biopsy (SLNB) for superstaging or isolated SLNB for minimal-invasive staging. The prospective study was designed to evaluate the technical feasibility with focus on solitary positive SLN.

RESULTS

Visualization of lymphatic vessels with bright fluorescence of the SLN was feasible in 46 of 47 patients. Eighteen of 19 nodal positive patients were correctly identified with a sensitivity of 94.7% in all patients after ALND. After immunohistochemistry, in 19 of 25 overall nodal positive patients (76%) the SLN was the only positive lymph node.

CONCLUSION

Fluorescence-guided imaging using fluorescence retention detection allows transcutaneous navigation with a high rate of solitary positive SLN identification as an alternative technique for further research.

Clinical efficacy and problems with CT lymphography in identifying the sentinel node in breast cancer

BACKGROUND

Combining a radioisotope with a dye-guided method is the best method for identification of the sentinel lymph nodes (SNs) in breast cancer. However, some institutions are limited to use of a dye-guided method alone. Recently, computed tomographic lymphography (CTLG) employing a nonionic contrast medium has achieved SN identification.

PATIENTS AND METHODS

218 patients with primary breast cancer and no clinical evidence of lymph node metastasis were studied. SN identification was performed by CTLG and a dye-guided method. The SN identification rate was analyzed for correlations with the clinicopathological findings.

RESULTS

The SN identification rates were 96% with CTLG, 92% with the dye-guided method and 99% with both methods combined. The identification rates with CTLG and the combined method were significantly lower in node-positive patients compared to node-negative patients, and significantly lower with the combined method in vascular invasion-positive patients compared to negative patients. In addition, the SN identification rate with the dye-guided method was significantly lower in patients with a body mass index (BMI) of > or = 25, whereas the BMI did not affect the identification rate with CTLG or the combined method. Multiple SNs were detected in approximately 20% of the patients.

CONCLUSION

Combined performance of CTLG and a dye-guided method enables identification of SNs prior to breast cancer surgery. That SN identification is easier compared with by the dye-guided method alone, and the identification rate is improved compared with either method alone. The combination of methods was especially useful in obese patients. For patients with multiple SNs, the combination has the further advantage of enabling accurate SN biopsy. CTLG may yield false-negative findings in node-positive patients and patients with lymph vessel obstruction.

Evaluation of sentinel lymph node metastasis alone guided by three-dimensional computed tomographic lymphography in video-assisted breast surgery

BACKGROUND

Detailed relations between lymph nodes and lymph flow can be clarified by three-dimensional computed tomographic (3D-CT) lymphangiography. Systematic collection of lymph nodes based on 3D-CT lymphangiography can decrease unnecessary lymph node dissection and attendant complications.

METHODS

To mark the sentinel lymph node (SLN) on the skin, 3D-CT lymphangiography was performed the day before the surgery. Iopamiron 300 (2 ml) was injected subcutaneously. A 16-channel multidetector-row helical CT scan image was reconstructed to produce a 3D image of lymph ducts and lymph nodes. Biopsy of SLN was performed by a dye-staining method using Visiport-aided endoscopy. Stained lymph nodes were located by following the dye in the lymph ducts on a video monitor. For SLN-metastasis-positive patients, standard axillary lymph node dissection (levels 1 and 2) was performed with video assistance.

RESULTS

Since December 2001, video-assisted breast surgery has been performed for 180 patients, SLN biopsy for 150 patients, and 3D-CT lymphangiography for 110 patients. Findings show that SLN-positive metastasis (n = 31) was accompanied by SLN metastasis alone in 14 patients. One-node metastasis, except for SLN, was observed in seven patients, two-node metastasis in three patients, and metastasis involving more than three nodes in seven patients. Review of the lymphoid path using 3D-CT lymphangiography confirmed that metastasis occurred in order of lymph flow.

CONCLUSIONS

Absence of metastasis in the second and third SLNs, even in patients with SLN metastasis, obviates the need for dissection of more nodes.

Video-assisted breast surgery and sentinel lymph node biopsy guided by three-dimensional computed tomographic lymphography

BACKGROUND

Video-assisted breast surgery (VABS) is a less invasive and aesthetically better option for benign and malignant breast diseases and for sentinel lymph node biopsy (SLNB). The authors have performed 150 VABS procedures since December 2001. They have examined the usefulness of three-dimensional computed tomographic (3D-CT) lymphography for detecting sentinel lymph nodes (SLNs) precisely, as well as the cosmetic and treatment results of VABS.

METHODS

In this study, VABS was performed with a 2.5-cm skin incision in the axilla or periareola (1 cm in the axilla for SLNB), using a retraction method, for mammary gland resection, SLNB, axillary lymph node dissection, and breast reconstruction under video assistance. On the day before the surgery, 3D-CT lymphography was performed to mark SLN on the skin. Above the tumor and near the areola, 2 ml of Iopamiron 300 was injected subcutaneously. A 16-channnel multidetector-row helical CT scan image was taken after 1 min and reconstructed to produce a 3D image. Sentinel lymph node biopsy was performed by the VABS technique using the Visiport.

RESULTS

The VABS procedure was performed for 19 benign and 131 malignant diseases, and 115 SLNBs (74 with 3D-CT) were performed. The SLNs were shown precisely by 3D-CT lymphography, as proved by a case of lymph node metastasis, in which accurate relationships between lymph ducts and SLNs were shown. These were classified into four patterns: a single duct to single node (40 cases), multiple ducts to a single node (13 cases), a single duct to multiple nodes (1 case), and multiple ducts to multiple nodes (12 cases). The SLNB procedure can be performed safely by 3D-CT lymphography and less invasively by VABS.

CONCLUSIONS

The findings show that 3D-CT lymphography is useful for performing precise SLNB using VABS.

Endoscopic video-assisted breast surgery: procedures and short-term results

BACKGROUND

We devised a new endoscopic operation for breast diseases. We report the aesthetic and treatment results of this procedure.

METHODS

A 2.5-cm axillary skin incision was made for a single approaching port, and a working space was created by retraction. Under video assistance, we resected the mammary gland partially or totally, and in the case of malignant diseases we also performed a sentinel lymph node biopsy and dissected axillary lymph nodes (levels I and II).

RESULTS

From December 2001 through April 2005, we performed endoscopic video-assisted breast surgery (VABS) in 100 patients with breast diseases. The diseases were benign in 18 patients and malignant in 82 patients. Of the malignant diseases, 80 underwent breast-conserving surgery and 2 underwent skin-sparing mastectomy. There was no significant difference in operation time, blood loss, or blood examinations related with the acute phase reaction between VABS and conventional breast-conserving procedures. All surgical margins were negative on examination of permanent histological preparations. The wounds healed without noticeable scarring. The original shapes of the breast were preserved. All patients expressed their great satisfaction with VABS.

CONCLUSIONS

VABS can be considered as a surgical option and can provide aesthetic advantages for patients with breast disease.

CT lymphography-navigated sentinel lymph node biopsy in patients with superficial esophageal cancer

BACKGROUND

To evaluate experimentally and clinically the feasibility of a newly developed technique of endoscopic computed tomography (CT) lymphography with endoscopic submucosal injection of iopamidol for esophageal sentinel lymph node (SLN) mapping and biopsy examination.

METHODS

Nine anesthetized dogs underwent CT after endoscopic submucosal injection of 2 mL iopamidol; 1.25-mm thick CT images were obtained before and at 1, 3, 5, 7, and 10 minutes after contrast injection. Clinically, 12 patients with superficial esophageal cancer (preoperative imaging stage: cT1, cN0) underwent CT lymphography in a similar fashion at 1, 5, and 10 minutes after peritumoral injection, followed by radical esophagectomy and regional lymph node dissection under CT lymphography guidance.

RESULTS

CT lymphography visualized the draining lymphatic vessels and SLNs within 5 minutes after contrast injection. All 14 SLNs in dogs (average, 1.5 nodes per animal; range, 1-2) and 28 SLNs in patients (average, 2.3 nodes per patient; range, 1-4) were found intraoperatively at the correct location under CT lymphography guidance. Lymph node metastasis could be detected with excellent sensitivity and accuracy in this small number of patients with no false-negative findings; metastasis was positive only in the preoperatively identified SLNs in 4 patients and in both SLNs and distant nodes in 1 patient, and was negative in all resected nodes in the remaining 7 patients.

CONCLUSIONS

Endoscopic CT lymphography appears to allow accurate identification of direction and locations of lymph flow and SLNs, and has the potential clinical applicability for esophageal SLN mapping and biopsy examination, but will require a large study to determine its accuracy and usefulness.

Lymphatic drainage from esophagogastric tract: feasibility of endoscopic CT lymphography for direct visualization of pathways

PURPOSE

To evaluate the feasibility of an endoscopic computed tomographic (CT) lymphography technique with submucosal injection of iopamidol for direct visualization of lymphatic drainage pathways in dogs and in patients with operable esophageal cancer.

MATERIALS AND METHODS

With institutional animal committee approval, a total of 2 mL of undiluted iopamidol was injected into the esophageal (n = 6) or gastric (n = 3) submucosa in nine dogs by using a flexible endoscope. Multi-detector row CT images (section thickness, 1.25 mm) were obtained before contrast material injection and during the 10 minutes after injection. The animals were euthanized so that their lymphatic anatomy could be examined. With ethical committee approval and patient informed consent, nine patients with esophageal cancer also underwent CT lymphography with peritumoral injection of 2 mL of iopamidol, followed by esophagectomy and regional lymph node dissection with CT lymphographic guidance. The histopathologic features of dissected nodes, including sentinel lymph nodes (SLNs), were examined.

RESULTS

CT lymphography depicted the direct connection of lymphatic drainage vessels with enhanced and/or unenhanced nodes (ie, SLNs) as early as within 5 minutes after contrast material injection in all subjects. All 13 SLNs in dogs (1.4 nodes per animal) and 18 SLNs in patients (two nodes per patient) were found and dissected at the correct location by using CT lymphographic guidance. In patients, histopathologic examination revealed the high predictive value of CT lymphographic-guided SLN biopsy: Only one of the preoperatively identified SLNs in three patients and both SLNs and adjacent nodes in two patients were positive for metastasis; all resected nodes in the remaining four patients were negative.

CONCLUSION

Endoscopic CT lymphography is a feasible method for visualizing the direct connection between and the accurate anatomic location of SLNs and lymphatic drainage vessels.

Video-Assisted Breast Surgery: Reconstruction after Resection of More than 33% of the Breast

BACKGROUND

Improvements in reconstructive mammoplasty methods have made it possible to resect more of the mammary gland while achieving good esthetic results in breast-conserving surgery. We report the esthetic results of extended wide resection of the breast with reconstruction procedures.

METHODS

Breast-conserving surgery was performed using a video-assisted breast surgery (VABS) technique. Breast reconstruction was simultaneously performed using the following three methods: mobilization of the remnant mammary gland, transplantation of the lateral tissue flap, and filling with an absorbent synthetic fiber mesh or cotton. The cosmetic results were evaluated with an original five-item-by-four-step scoring system: ABNSW-assessing asymmetry, breast shape, nipple shape, skin condition, and wound scar.

RESULTS

From December 2001 through March 2006, we performed endoscopic VABS in 130 patients with breast diseases. The candidates were 29 patients with breast cancer who required resection of more than 33% of the mammary gland because of ductal carcinoma in situ (1 patient), multiple cancers (6 patients), widely extended lesions (20 patients), and lesions after preoperative systemic therapy (2 patients). Twenty-one patients underwent resection of 33% to 50% of the breast, and 8 underwent resection of more than 50% of the breast. All surgical margins were negative on examination of permanent histological preparations. The original shape of the breast was preserved. There was no local recurrence after follow-up times of 33 months (maximum) and 19 months (average).

CONCLUSIONS

The newly devised reconstruction methods with VABS can markedly increase the mammary gland resection volume while achieving a good esthetic outcome, ensuring a precise disease-free surgical margin, and expanding the indications for breast-conserving therapy.

Breast Sentinel Lymph Node Navigation With Three-Dimensional Interstitial Multidetector-Row Computed Tomographic Lymphography

OBJECTIVE

Three-dimensional multidetector-row computed tomographic lymphography (3D MDCT-LG) with interstitial injection of a widely available nonionic monometric contrast medium iopamidol was used for navigation of breast sentinel lymph node (SLN) biopsy.

METHODS

3D MDCT-LG was obtained after massage of the interstitially injection sites of a total of 4-5 mL undiluted iopamidol at periareolar and peritumoral areas in 68 consecutive patients with early-stage breast cancer, using a 4 detector-row CT scanner. Drainage lymphatic patterns and SLN anatomy were assessed on 3D MDCT-LG images. 3D MDCT-LG-navigated SLN biopsy with combined use of blue dye was followed by backup axillary lymph node dissection to evaluate accuracy of SLN biopsy.

RESULTS

The 3D MDCT-LG images clearly localized primary SLNs by visualizing the direct connection between these nodes and their afferent lymphatic vessels on detailed anatomy of the surrounding structures in all patients. Drainage lymphatic pathways on these images were classified into 4 patterns: single route/single SLN (39 cases, 57%), multiple routes/multiple SLNs (10 cases, 15%), single route/multiple SLNs (9 cases, 13%), and multiple routes/single SLN (10 cases, 15%). Under 3D MDCT-LG navigation, SLNs was found at the accurate location in all patients. With backup axillary lymph node dissection, metastasis was found in 14 (20%) patients, and 8 of these patients had metastasis only in the preoperatively identified SLNs. In other 5 positive patients, metastasis was found both in the SLN and non-SLNs. However, micrometastasis eventually was found only in non-SLN in an elderly patient. Overall, the sensitivity, false-negative rate, and accuracy of 3D CT-L-navigated SLN biopsy were 92% (13/14 patients), 7% (1/14 patients), and 98% (67/68 patients), respectively.

CONCLUSIONS

Topographic 3D interstitial MDCT-LG can be a widely available and reliable navigator for breast SLN biopsy.

Preoperative imaging of the lung sentinel lymphatic basin with computed tomographic lymphography: a preliminary study

BACKGROUND

Preoperative localization of the sentinel node basin would guide selective lymph node dissection. We tried to identify these nodal stations with indirect computed tomographic lymphography using a conventional extracellular contrast agent, iopamidol.

METHODS

Eleven consecutive patients scheduled to undergo anatomic resection of suspected lung cancer, without lymphadenopathy, were given a peritumoral injection of undiluted iopamidol under computed tomography guidance, and lymphatic migration was assessed by multidetector-row helical computed tomography.

RESULTS

There were no complications such as bleeding, pneumothorax, or allergic reactions. Enhanced nodes were detected in all but 1 patient who had diffuse lymph nodal calcification. Enhanced nodes were identified at 32 ipsilateral intrathoracic nodal stations (20 hilar stations and 12 mediastinal stations). The average length of the longer axis of the enhanced nodes was 4.8 mm (range, 3 to 8 mm), and the average attenuation of the enhanced nodes was 132 (range, 46 to 261) Hounsfield units. In 9 patients with confirmed lung cancer, enhanced nodes appeared at 26 nodal stations, and all apparent enhanced nodes were identified as actual lymph nodes at appropriate position during lymphadenectomy. None of the resected lymph nodes had metastatic involvement.

CONCLUSIONS

Indirect computed tomographic lymphography with the peritumoral injection of iopamidol effectively depicts the drainage nodes unless they are diffusely calcified. Although further study is required, this method could guide selective lymph node dissection.

3-Dimensional Computed Tomography Lymphography–Guided Identification of Sentinel Lymph Nodes in Breast Cancer Patients Using Subcutaneous Injection of Nonionic Contrast Medium

OBJECTIVE

Simple and reliable identification methods for sentinel lymph nodes (SLNs) which do not use radioisotope are essential for early breast cancer patients in community hospitals in Japan. The purpose of this paper is to demonstrate the feasibility and efficacy of computed tomography (CT) lymphography for SLN detection.

METHODS

The study included 15 cases with T1 or T2 breast cancer. After subcutaneous injection of 1 mL of iopamidol in 1 subareolar area of the affected breast, CT scanning was carried out and 3-dimensional (3D) CT images were created. SLNs predicted from images and CT values were assessed as to whether they were identical to those identified by the dye method.

RESULTS

An enhanced lymph vessel draining into SLN was demonstrated in 11 cases (73%) and an enhanced SLN in 10 cases (67%). 3D images clearly revealed the anatomic relationship between lymph vessels, SLN, and the surrounding structures. In addition, SLN could be predicted by the change of CT value in the time-course in another case. In total, SLN in 13 cases (87%) could be predicted. All SLNs suggested from CT lymphography were identified by the dye method. No significant adverse effect was noted in any case.

CONCLUSIONS

The present clinical trial indicated that subcutaneous injection of nonionic contrast medium with CT scanning seems to be a promising method for the demonstration of a draining lymph vessel and SLN. The CT value time-course may also provide some important information. Further trials will be needed for the successful establishment of this CT lymphography-guided method for SLN identification.

Breast sentinel lymph node mapping at CT lymphography with iopamidol: preliminary experience

PURPOSE

To evaluate sentinel lymph node (SLN) mapping with interstitial computed tomographic (CT) lymphography with small volumes of iopamidol for direction of SLN biopsy in breast cancer.

MATERIALS AND METHODS

Thin-section transverse and three-dimensional CT images that included the breast and axilla were acquired at multi-detector row helical CT in 17 patients with operable breast cancer before subcutaneous injection of 2 mL of undiluted iopamidol into peritumoral and periareolar areas and 1-5 minutes after massage of injection sites. Location and size of SLNs were assessed at CT lymphography and were compared with SLNs at standard axillary lymph node dissection with blue dye staining.

RESULTS

CT lymphography allowed localization of SLNs in all patients by means of visualization of a direct connection between an SLN and its afferent lymphatic vessels draining from the injection sites. Afferent vessels were joined and drained into a single axillary SLN, except in four patients with two or three SLNs, including a parasternal one. SLNs did not enhance because of rerouting of lymph flow in four patients. At surgery, SLNs that were stained or not stained with blue dye were easily found with CT lymphographic guidance. Tumoral infiltration was not evident in any resected nodes, except for infiltration in one patient with micrometastasis in SLN alone and infiltration in four patients with massive metastasis in both SLN and distant nodes.

CONCLUSION

Because preoperative CT lymphography-guided SLN mapping provides SLN position with detailed lymphatic anatomy, it may be useful for the direction of breast SLN biopsy.