Intra-operative sentinel lymph node identification using a novel receptor-binding agent (technetium-99m neomannosyl human serum albumin, 99mTc-MSA) in stage I non-small cell lung cancer

Detection of metastatic lymph node and sentinel lymph node mapping ​using mannose receptor targeting in in vivo mouse footpad tumor models and rabbit uterine cancer models

BACKGROUND

This study aimed to evaluate the effectiveness of neo-mannosyl human serum albumin-indocyanine green (MSA-ICG) for detecting metastatic lymph node (LN) and mapping sentinel lymph node (SLN) using mouse footpad uterine tumor models. Additionally, the authors assessed the feasibility of MSA-ICG in SLN mapping in rabbit uterine cancer models.

MATERIALS AND METHODS

The authors compared the LN targeting ability of MSA-ICG with ICG. Six mouse footpad tumor models and two normal mice were each assigned to MSA-ICG and ICG, respectively. After the assigned tracers were injected, fluorescence images were taken, and the authors compared the signal-to-background ratio (SBR) of the tracers. A SLN biopsy was performed to confirm LN metastasis status and CD206 expression level. Finally, an intraoperative SLN biopsy was performed in rabbit uterine cancer models using MSA-ICG.

RESULTS

The authors detected 14 groin LNs out of 16 in the MSA-ICG and ICG groups. The SBR of the MSA-ICG group was significantly higher than that of the ICG group. The metastatic LN subgroup of MSA-ICG showed a significantly higher SBR than that of ICG. CD206 was expressed at a high level in metastatic LN, and the signal intensity difference increased as the CD206 expression level increased. SLN mapping was successfully performed in two of the three rabbit uterine cancer models.

CONCLUSIONS

MSA-ICG was able to distinguish metastatic LN for an extended period due to its specific tumor-associated macrophage-targeting property. Therefore, it may be a more distinguishable tracer for identifying metastatic LNs and SLNs during uterine cancer surgery. Further research is needed to confirm these results.

Radioisotope-Guided Excision of Mediastinal Lymph Nodes in Patients with Non-Small Cell Lung Carcinoma: Feasibility and Clinical Impact

BACKGROUND

Intraoperative localisation of nodal disease in non-small cell lung cancer (NSCLC) can be challenging. Lymph node localisation via radiopharmaceuticals is used in many conditions; we tested the feasibility of this approach in NSCLC.

METHODS

NSCLC patients were prospectively recruited. Intraoperative peri-tumoral injections of [99mTc]Tc-albumin nanocolloids were performed, followed by removing the tumour and locoregional lymph nodes. These were examined ex vivo with a gamma probe and labelled sentinel lymph nodes (SLNs) if they showed any activity or non-sentinel lymph nodes (nSLNs) if they did not. Thereafter, the surgical field was scanned with the probe; any further radioactive lymph node was removed and labelled as "extra" SLNs (eSLNs). All specimens were sent to histology, and metastatic status was recorded.

RESULTS

48 patients were enrolled, and 290 nodal stations were identified: 179 SLNs, 87 nSLNs, and 24 eSLNs. A total of 44 nodal metastases were identified in 22 patients, with 36 of them (82%) located within SLNs. Patients with nSLNs metastases had at least a co-existing positive SLN. No metastases were found in eSLNs.

CONCLUSIONS

The technique shows high sensitivity for intraoperative nodal metastases identification. This information could allow selective lymphadenectomies in low-risk patients or more aggressive approaches in high-risk patients.

Clinical translational barriers against nanoparticle-based imaging agents

Nanoparticle based imaging agents (NIAs) have been intensively explored in bench studies. Unfortunately, only a few cases have made their ways to clinical translation. In this review, clinical trials of NIAs were investigated for understanding possible barriers behind that. First, the complexity of multifunctional NIAs is considered a main barrier because it brings uncertainty to batch-to-batch fabrication, and results in sophisticated in vivo behaviors. Second, inadequate biosafety studies slow down the translational work. Third, NIA uptake at disease sites is highly heterogeneous, and often exhibits poor targeting efficiency. Focusing on the aforementioned problems, key design parameters were analyzed including NIAs' size, composition, surface characteristics, dosage, administration route, toxicity, whole-body distribution and clearance in clinical trials. Possible strategies were suggested to overcome these barriers. Besides, regulatory guidelines as well as scale-up and reproducibility during manufacturing process were covered as they are also key factors to consider during clinical translation of NIAs.

Sentinel lymph node biopsy for lung cancer

Sentinel lymph node biopsy is a technique to identify the first lymph node (or nodes) draining a tumor. The underlying principle is that as the first site of cancer spread, evaluation of the sentinel node will be most predictive for wider nodal involvement. The introduction of sentinel node biopsy revolutionized the surgical management of cutaneous melanoma and breast cancer, becoming a key component in the management of such patients. For over 20 years, thoracic surgeons have similarly worked to apply this technique to lung cancer but have thus far not had the same impact on lung surgery. In this review, we will summarize the ongoing discussions on the role of sentinel node biopsy in lung cancer, the methods for identifying the sentinel node, and the techniques for evaluating the sentinel node specimen. We will also highlight some of the pressing questions investigators should consider when designing a trial for sentinel node mapping. This will clarify the current status of sentinel node biopsy in lung cancer and thus highlight important future directions for research.

Phase 0 Clinical Trial Strategies for the Neurosurgical Oncologist

In an era of escalating drug discovery costs, shifting priorities within the pharmaceutical industry, and longstanding challenges in central nervous system drug delivery, surgical trials offer an avenue to identify promising agents with demonstrable tumor penetration and molecular effects. The rise of pharmacodynamic- and pharmacokinetic-driven clinical trials, including phase 0 study designs, creates an opportunity for the neurosurgical oncologist to engage drug development for brain tumor patients directly. Here, we review the phase 0 clinical trial mechanism as well as its current and future applications within neurosurgical oncology.

A prediction model for lymph node metastases using pathologic features in patients intraoperatively diagnosed as stage I non-small cell lung cancer

Background

There is little information on which pattern should be chosen to perform lymph node dissection for stage I non-small-cell lung cancer. This study aimed to develop a model for predicting lymph node metastasis using pathologic features of patients intraoperatively diagnosed as stage I non-small-cell lung cancer.

Methods

We collected pathology data from 284 patients intraoperatively diagnosed as stage I non-small-cell lung cancer who underwent lobectomy with complete lymph node dissection from 2013 through 2014, assessing various factors for an association with metastasis to lymph nodes (age, gender, pathology, tumour location, tumour differentiation, tumour size, pleural invasion, bronchus invasion, multicentric invasion and angiolymphatic invasion). After analysing these variables, we developed a multivariable logistic model to estimate risk of metastasis to lymph nodes.

Results

Univariate logistic regression identified tumour size >2.65 cm (p < 0.001), tumour differentiation (p < 0.001), pleural invasion (p = 0.034) and bronchus invasion (p < 0.001) to be risk factors significantly associated with the presence of metastatic lymph nodes. On multivariable analysis, only tumour size >2.65 cm (p < 0.001), tumour differentiation (p = 0.006) and bronchus invasion (p = 0.017) were independent predictors for lymph node metastasis. We developed a model based on these three pathologic factors that determined that the risk of metastasis ranged from 3% to 44% for patients intraoperatively diagnosed as stage I non-small-cell lung cancer. By applying the model, we found that the values ŷ > 0.80, 0.43 < ŷ ≤ 0.80, ŷ ≤ 0.43 plus tumour size >2 cm and ŷ ≤0.43 plus tumour size ≤2 cm yielded positive lymph node metastasis predictive values of 44%, 18%, 14% and 0%, respectively.

Conclusions

A non-invasive prediction model including tumour size, tumour differentiation and bronchus invasion may be useful to give thoracic surgeons recommendations on lymph node dissection for patients intraoperatively diagnosed as Stage I non-small cell lung cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3273-x) contains supplementary material, which is available to authorized users.

The predictive accuracy of sentinel nodes mapping in the setting of pulmonary metastasectomy

This is the first study to evaluate the feasibility of mediastinal lymph node dissection (MLND) based on sentinel lymph node (SLN) status during pulmonary metastasectomy. A total of 22 patients (16 men, 6 women; age 63.3 ± 7.01 years) who were candidates for metastasectomy through segmentectomy or lobectomy with MLND owing to cancers metastatic to the lung were enrolled in this study. Radiotracer was administered at the peritumoral region before surgery or soon after initiating surgery. During the operation, the radioactivity of the lymph nodes (ex vivo) was counted with a handheld gamma probe after MLND. Lobectomy was performed in 17 patients, and segmentectomy, in 5 patients. The number of dissected lymph nodes per patient was 14.4 ± 8.69 (range, 5–36). In all patients, the SLN could be detected, and the number of SLNs identified was 2.0 ± 1.15 (range, 1–5) per patient. Lymph node metastasis was identified in 3 of the 22 patients (13.6%), and none of the 3 patients with N1 or N2 disease had false-negative SLNs. SLN identification might be an indicator of whether or not MLND should be performed during pulmonary metastasectomy. However, further large-volume and multi-institutional studies are needed.

Macrophage-Targeted Indocyanine Green-Neomannosyl Human Serum Albumin for Intraoperative Sentinel Lymph Node Mapping in Porcine Esophagus

BACKGROUND

The sentinel lymph node (SLN) concept has been proposed to avoid unnecessary invasive LN dissection in surgery for esophageal cancer. This study evaluated a new macrophage-targeting fluorescent agent, indocyanine green-neomannosyl human serum albumin (ICG:MSA), for SLN mapping using a custom-made intraoperative color and fluorescence-merged imaging system (ICFIS) in porcine esophagus.

METHODS

The LN targeting ability of ICG:MSA, indocyanine green-human serum albumin (ICG:HSA), and ICG was examined in vitro using the U937 differentiated monocyte cell line and in vivo in a mouse footpad model using fluorescence imaging. SLN identification in rabbit esophagus was then performed using ICG:MSA, ICG:HSA, and ICG. Finally, intraoperative SLN detection was conducted in porcine esophagus after esophagoscopic injection of ICG:MSA.

RESULTS

The fluorescence signal of U937 cells treated by ICG:MSA was significantly higher than that of ICG or ICG:HSA (ICG: 1.0 ± 0.37; ICG:HSA: 3.4 ± 0.28, ICG:MSA: 6.8 ± 1.61; ICG to ICG:HSA, p = 0.03; ICG:HSA to ICG:MSA, p = 0.04; ICG to ICG:MSA, p = 0.0009). ICG:MSA was retained in popliteal LNs as long as 3 h, while ICG rapidly diffused through the entire mouse lymphatic system within 5 min. Esophageal SLN was detected within 15 min after injection of either ICG or ICG:MSA, but ICG:MSA provided more distinguishable images of LNss than ICG in rabbit esophagus. The SLN was also successfully detected in all porcine esophagus; the mean number of SLNs identified per esophagus was 1.6 ± 0.55.

CONCLUSIONS

ICG:MSA has more specific macrophage-targeting properties, which could overcome the limitation of the low SLN retention of ICG, and could provide more precise real-time SLN detection during esophageal cancer surgery.

Application of albumin-based nanoparticles in the management of cancer

Over the past three decades, tremendous progress has been made in cancer prevention and treatment. Despite these advances, a substantial number of cancer cases experience early recurrence and metastases. Thus, the better management of cancer, especially developing more effective drugs for combating cancer cells, is an arduous task. Albumin-based nanoparticles are emerging as a promising approach to replace the traditional way of carrying therapeutic drugs to a tumor site. In this review, we describe the basic knowledge on albumin-based nanoparticles, recent progress of using albumin-based nanoparticles in the diagnosis and treatment of cancer, and the application of nanoparticle albumin bound (Nab) paclitaxel for the treatment of lung, breast and pancreatic cancer. Last but not least, we try to discuss future goals and perspectives in the field of drug delivery research, thereby facilitating the antitumor activity.

Single-port video-assisted thoracoscopic pulmonary segmentectomy: a report on 30 cases†

OBJECTIVES

This study aimed to evaluate the feasibility of a single-port video-assisted thoracoscopic surgery for pulmonary segmentectomy in patients with malignant or benign lung diseases.

METHODS

Thirty patients (17 women; mean age, 61.7 ± 10.9 years) who underwent a single-port thoracoscopic segmentectomy were consecutively included in this study. A 2- to 4-cm incision was made at the fifth intercostal space on the anterior or posterior axillary line, depending on the tumour location. We investigated the postoperative outcomes according to the size of the incision (2 vs 3-4 cm) or the location of segmentectomy.

RESULTS

Fifteen primary lung cancers, 5 metastatic lung cancers, 1 pulmonary sarcoma, 7 cases of inflammatory lung disease and 2 benign lung tumours were diagnosed. A 3- to 4-cm incision was used in 16 patients (53.3%), and a 2-cm incision in 14 patients. The most frequent segment removed was the left upper division (9 patients, 30%). A single-port thoracoscopic segmentectomy was completed in all of the patients except one (96.7%). This 1 patient underwent lobectomy instead because the lesion was not found in the initial segment removed. The mean operation time was 159 ± 56 min, and no significant difference in the size of incision was observed (P = 0.651). The right middle and superior segments tended to require shorter operation times (97.1 ± 44.9 min) than the other segments (p < 0.001). One patient died (3.3%) because of septic shock. The chest tube drain was removed 4.6 ± 1.6 days after the operation.

CONCLUSIONS

This study results suggest that a single-port thoracoscopic surgery might be a feasible option for pulmonary segmentectomy with acceptable postoperative outcomes in the early stages of lung cancer or for benign lung disease.

Current innovations in sentinel lymph node mapping for the staging and treatment of resectable lung cancer

Despite surgical resectability, early-stage lung cancer remains a challenge to cure. Survival outcomes are hindered by variable performance of adequate lymphadenectomy and the limitations of current pathologic nodal staging. Sentinel lymph node (SLN) mapping, a mainstay in the management of breast cancer and melanoma, permits targeted nodal sampling for efficient and accurate staging that can influence both intraoperative and adjuvant treatment decisions. Unfortunately, standard SLN identification techniques with blue dye and radiocolloid tracers have not been shown to be reproducible in lung cancer. In more recent years, intraoperative near-infrared image-guided lung SLN mapping has emerged as promising technology for the identification of the tumor-associated lymph nodes most likely to contain metastatic disease. Additionally, the clinical relevance of SLN mapping for lung cancer remains pressing, as the ability to identify micrometastatic disease in SLNs could facilitate trials to assess chemotherapeutic response and the clinical effect of occult nodal disease. This review outlines the status of lung cancer lymphatic mapping and techniques in development that may help close the gap between translational research in this field and routine clinical practice.

Needlescopic resection of small and superficial pulmonary nodule after computed tomographic fluoroscopy-guided dual localization with radiotracer and hookwire

PURPOSE

The aim of this study was to evaluate the feasibility of a needlescopic resection for small and superficial pulmonary nodules after dual localization with radiotracer and hookwire.

METHODS

Computed tomography (CT) fluoroscopy-guided dual marking with hookwire and (99m)Tc-phytate was performed on 36 small and superficial pulmonary nodules of 34 patients, just before the needlescopic procedure. This method was carried out through one introducer needle, after an initial single puncture. After detection of the hookwire-marked site through needlescopy, the precise lesion was confirmed using a thoracoscopic gamma probe by calculating the highest radioactivity. The pulmonary nodule was resected and diagnosed by pathologic examination.

RESULTS

The mean size of the nodules was 12.5 ± 5.4 mm (range 3-20), and their mean distance from the pleural surface was 5.6 ± 5.8 mm (range 0-18.7). The time of the dual localization procedure was 10.8 ± 3.6 min (range 5-18). Pneumothorax was developed in 6 of 34 patients (17.6 %) after preoperative localization, but did not require any treatment. Seven hookwires dislodged during the operation. Nevertheless, radiotracer markings detected on a gamma probe guided a successful wedge resection without difficulty in all seven cases. All nodules were successfully resected under needlescopy, except conversion to the 5-mm-sized thoracoscopy in four patients due to pleural adhesion.

CONCLUSIONS

Dual marking with radiotracer and hookwire under CT fluoroscopy is a safe and not time-consuming procedure, and has made needlescopy-assisted lung resection for small and superficial nodules or ground-glass opacity lesions easier, more convenient, and less hazardous.

Thoracoscopic color and fluorescence imaging system for sentinel lymph node mapping in porcine lung using indocyanine green-neomannosyl human serum albumin: intraoperative image-guided sentinel nodes navigation

PURPOSE

This study was performed to validate a newly developed sentinel lymph node (SLN) targeting tracer, indocyanine green-neomannosyl human serum albumin (ICG:MSA), and a thoracoscopic version of the intraoperative color and fluorescence imaging system (ICFIS) for lung cancer SLN mapping.

METHODS

ICG alone or ICG:MSA (5 μg/kg) was injected into the rat thigh, and the results were compared. The fluorescence signal-to-background ratios of SLNs were recorded and evaluated over a 2-h period by using ICFIS. Additionally, a SLN biopsy was performed via video-assisted thoracoscopic surgery with the use of ICG:MSA in porcine lung by using thoracoscopic ICFIS.

RESULTS

The newly developed ICG:MSA showed a significantly improved signal-to-background ratio compared with ICG alone throughout the trials. All SLNs were identified in both rats (ten SLNs in ten rat thighs) and pigs (ten SLNs in ten porcine lungs) under in vivo conditions. All SLNs were dissected successfully by using video-assisted thoracoscopic surgery with the help of thoracoscopic ICFIS.

DISCUSSION

ICG:MSA accumulates in the SLN by uptake and retention through the mannose-specific receptors on macrophages. Thoracoscopic ICFIS successfully assisted SLN mapping despite low near-infrared light transmission in the commercial thoracoscope. On the basis of the results of the thoracoscopic SLN mapping, we anticipate that ICG:MSA and thoracoscopic ICFIS can be translated to clinical trials in the near future.

Sialyl Lewis X as a predictor of skip N2 metastasis in clinical stage IA non-small cell lung cancer

Background

Radical segmentectomy has been performed for small-sized non-small cell lung cancer (NSCLC). However, underestimation of mediastinal lymph node metastasis in the absence of hilar or interlobar metastasis (skip N2) affects surgical strategy. Our aim was to investigate preoperative and intraoperative predictors of skip N2 in clinical stage (c-stage) IA NSCLC.

Methods

From 1998 to 2011, 279 patients (155 men and 124 women) with c-stage IA NSCLC (230 pN0, 17 pN1, 12 skip N2, 20 non-skip N2) underwent systematic lobectomy (R0 resection) at our institute. We compared preoperative serum concentrations of carcinoembryonic antigen, cytokeratin 19 fragment, sialyl Lewis X (SLX), and pre- and intraoperative clinicopathological features of pN0 and skip N2 patients. Receiver operator characteristic (ROC) curve analysis was performed to distinguish between the two patient groups.

Results

The 5-year survival rate of skip N2 patients was 78.6%, higher than that of non-skip N2 patients (44.9%), and not significantly different than that of pN0 (86.7%) or pN1 patients (82.4%). The mean serum SLX concentration in skip N2 patients (28.0 U/ml) was elevated compared to that in pN0 patients (22.9 U/ml). In ROC analysis of SLX, the area under the curve was 0.710, and the optimal cut-off value was 21.4 U/ml (sensitivity, 91.7%; specificity, 51.7%). In multivariate analysis, SLX was an independent predictor of skip N2 in patients with c-stage IA NSCLC (odds ratio, 9.43; p = 0.006).

Conclusions

Skip N2 metastasis is common in patients with c-stage IA NSCLC with high serum SLX, and lobectomy with complete dissection of hilar and mediastinal lymph nodes should remain the standard surgical procedure for these cases.

Intraoperative nodal staging: role of sentinel node technology

In cases of superficial malignancies such as melanoma or breast cancer, intraoperative lymph node mapping with a sentinel lymph node (SLN) biopsy is an effective and minimally invasive alternative to inguinal or axillary lymph node dissection for early-stage tumors. For primary lung cancer, although much effort has been made to investigate a variety of tracers, such as dyes, radioisotopes, magnetite, and iopamidol, for discerning SLNs, an appropriate agent that produces high identification and accuracy rates has yet to be developed. Further studies are needed to find an ideal tracer for practical use in patients with non-small cell lung cancer.

The feasibility of a Two-incision video-assisted thoracoscopic lobectomy

Background

This study is to evaluate the feasibility and safety of video-assisted thoracoscopic (VATS) lobectomy with two incisions.

Methods

A total of 73 patients (male 47, female 26; mean age 61.2 ± 12.00 years old) who underwent major pulmonary resection, through VATS, using two incisions were included in this study. The thoracoscopy port was placed at the 7th or the 8th intercostal space in the mid-axillary line, and the working port, 3~5 cm long, at the 5th intercostal space, on the operator’s side.

Results

The preoperative diagnosis was benign lung disease in 8 patients (11.0%) and malignant lung disease in 65 (89.0%). Two patients (3.1%) needed a third port during surgery due to severe pleural adhesion, and conversion to thoracotomy was needed in 5 (6.8%), due to bleeding at pulmonary arterial branch (n = 3), anthracofibrotic lymph nodes around pulmonary artery (n = 1), and severe pleural adhesion (n = 1). The mean duration of the operation in the 66 patients, completed by a two-incision VATS lobectomy, was 163.4 ± 30.40 minutes. In 56 cases, which were completed by a two-incision VATS lobectomy for primary lung cancer, a total number of dissected lymph nodes per patient were 20.2 ± 11.2. The chest tube was removed on postoperative day 5.4 ± 2.8, and there was no occurrence of major perioperative morbidity and mortality.

Conclusions

Two-incision VATS lobectomy is applicable in the selected cases, and may obtain similar results with the conventional VATS lobectomy, through a certain period of learning curve.

Intraoperative combined color and fluorescent images-based sentinel node mapping in the porcine lung: comparison of indocyanine green with or without albumin premixing

OBJECTIVES

We developed a multimodal optical imaging system for intraoperative visualization of sentinel lymph nodes (SLNs). This study is to validate our system by showing SLNs in the lung through combined optical color and fluorescent image with indocyanine green (ICG) and ICG with human serum albumin (HSA).

METHODS

Identical ICG concentrations of ICG only or ICG:HSA was injected into the rat footpad and porcine lung. Absolute amounts of the fluorescents were scaled on the basis of animal weights. The entire procedures were recorded using color and near-infrared (NIR) charge-coupled device (CCD) cameras simultaneously, and the 2 images were merged by real-time image processing software. All fluorescence intensity signals to background ratio (SBR) and retention rates at SLN for both fluorescents were estimated and compared.

RESULTS

This newly developed intraoperative color and fluorescence optical imaging system successfully visualized the SLNs in animal experiments. The SLNs were identified 100% for both rat and pig under in vivo conditions. Real-time image processing software overcame the low signal of NIR fluorescence images. ICG and ICG:HSA provided no significantly different SBR in the SLN images for both rat thigh and pig lung.

CONCLUSIONS

The intraoperative optical imaging system enabled real-time image-guided surgery during SLN mapping in lung in an animal model. The ICG retention rate was similar to ICG:HSA. ICG alone can be useful for SLN imaging during lung cancer surgery.

Quantitative study of lung perfusion SPECT scanning and pulmonary function testing for early radiation-induced lung injury in patients with locally advanced non-small cell lung cancer

Radiation lung injury is a common side-effect of pulmonary radiotherapy. The aim of this study was to quantitatively assess early changes in lung perfusion single photon emission computed tomography (SPECT) scanning and pulmonary function testing (PFT) prior to and after intensity modulated radiotherapy (IMRT) for patients suffering from locally advanced non-small cell lung cancer (LANSCLC). Twenty patients with LANSCLC received lung perfusion SPECT scanning and PFT prior to IMRT and immediately after IMRT. Lung perfusion index (LPI) was calculated after the quantification of perfusion SPECT images. The LPI of the two groups was analyzed by matched t-test. The radioactive count of each layer of single lung was added to obtain the sum of the irradiated area. The percentage of the irradiated area of single lung was calculated. Linear correlation analysis was carried out between the percentage of the irradiated area and LPI in order to verify the validity of LPI. In this study, LPI and the percentage of the irradiated area of single lung exhibited an excellent correlation either prior to or after IMRT (r=0.820 and r=0.823, respectively; p<0.001). There was no statistically significant difference between pre-IMRT LPI and post-IMRT LPI (p=0.135). LPI in the group receiving a radical dose had no statistically significant difference (p=0.993), however, it showed a statistically significant difference in the group receiving a non-radical dose (p=0.025). In the non-radical dose group, the post-IMRT LPI was larger compared to pre-IMRT. None of the parameters of PFT exhibited a statistically significant difference prior to and after IMRT (p>0.05). The quantitative method of lung perfusion SPECT scanning can be used to evaluate changes in perfusion early in patients receiving a non-radical dose (BED ≤126,500 cGy) IMRT. Evaluating early changes in global lung function using the current method of PFT is difficult, since time can be a contributing factor for radiation-induced lung injury.

Clinical impact of serum proteins on drug delivery

Among serum proteins albumin and transferrin have attracted the most interest as drug carriers in the past two decades. Prior to that, their potential use was overshadowed by the advent of monoclonal antibodies that was initiated by Milstein and Koehler in 1975. Meanwhile intensive pursuit of exploiting transferrin, but above all albumin as an exogenous or endogenous carrier protein for treating various diseases, primarily cancer, rheumatoid arthritis, diabetes and hepatitis has resulted in several marketed products and numerous clinical trials. While the use of transferrin has clinically been primarily restricted to immunotoxins, albumin-based drug delivery systems ranging from albumin drug nanoparticles, albumin fusion protein, prodrugs and peptide derivatives that bind covalently to albumin as well as physically binding antibody fragments and therapeutically active peptides are in advanced clinical trials or approved products. For treating diabetes, Levemir and Victoza that are myristic acid derivatives of human insulin or glucagon-like peptide 1 (GLP-1) act as long-acting peptides by binding to the fatty acid binding sites on circulating albumin to control glucose levels. Levemir from Novo Nordisk has already developed into a blockbuster since its market approval in 2004. Abraxane, an albumin paclitaxel nanoparticle as a water-soluble galenic formulation avoiding the use of cremophor/ethanol, transports paclitaxel through passive targeting as an albumin paclitaxel complex to the tumor site and is superior to conventional Taxol against metastatic breast cancer. INNO-206, an albumin-binding doxorubicin prodrug that also accumulates in solid tumors due to the enhanced permeability and retention (EPR) effect but releases the parent drug through acid cleavage, either intra- or extracellularly, is entering phase II studies against sarcoma. An expanding field is the use of albumin-binding antibody moieties which do not contain the fragment crystallizable (Fc) portion of, conventional immunoglobulin G (IgG) but are comprised of monovalent or bivalent light and/or heavy chains and incorporate an additional albumin-binding peptide or antibody domain. The most advanced antibody of this kind is ATN-103 (Ozoralizumab), a trivalent albumin-binding nanobody that neutralizes the pro-inflammatory tumor necrosis factor alpha (TNF-α) as a causative agent for exacerbating rheumatoid arthritis. ATN-103 is currently in multi-center phase II trials against this debilitating disease. In summary, because albumin as the most abundant circulating protein cannot only be used to improve the pharmacokinetic profile of therapeutically relevant peptides and the targeting moiety of antibodies but also for peptide-based targeting as well as low-molecular weight drugs to inflamed or malignant tissue, it is anticipated that R&D efforts of academia and the pharmaceutical industry in this field of drug delivery will prosper.

Impact of albumin on drug delivery--new applications on the horizon

Over the past decades, albumin has emerged as a versatile carrier for therapeutic and diagnostic agents, primarily for diagnosing and treating diabetes, cancer, rheumatoid arthritis and infectious diseases. Market approved products include fatty acid derivatives of human insulin or the glucagon-like-1 peptide (Levemir(®) and Victoza(®)) for treating diabetes, the taxol albumin nanoparticle Abraxane(®) for treating metastatic breast cancer which is also under clinical investigation in further tumor indications, and (99m)Tc-aggregated albumin (Nanocoll(®) and Albures(®)) for diagnosing cancer and rheumatoid arthritis as well as for lymphoscintigraphy. In addition, an increasing number of albumin-based or albumin-binding drugs are in clinical trials such as antibody fusion proteins (MM-111) for treating HER2/neu positive breast cancer (phase I), a camelid albumin-binding nanobody anti-HSA-anti-TNF-α (ATN-103) in phase II studies for treating rheumatoid arthritis, an antidiabetic Exendin-4 analog bound to recombinant human albumin (phase I/II), a fluorescein-labeled albumin conjugate (AFL)-human serum albumin for visualizing the malignant borders of brain tumors for improved surgical resection, and finally an albumin-binding prodrug of doxorubicin (INNO-206) entering phase II studies against sarcoma and gastric cancer. In the preclinical setting, novel approaches include attaching peptides with high-affinity for albumin to antibody fragments, the exploitation of albumin-binding gadolinium contrast agents for magnetic resonance imaging, and physical or covalent attachment of antiviral, antibacterial, and anticancer drugs to albumin that are permanently or transiently attached to human serum albumin (HSA) or act as albumin-binding prodrugs. This review gives an overview of the expanding field of preclinical and clinical drug applications and developments that use albumin as a protein carrier to improve the pharmacokinetic profile of the drug or to target the drug to the pathogenic site addressing diseases with unmet medical needs.

Sentinel node identification using technetium-99m neomannosyl human serum albumin in esophageal cancer

BACKGROUND

This study is a clinical trial designed to test the reliability and feasibility of sentinel node detection using a new mannose receptor radioactive binding agent in patients with esophageal squamous cell carcinoma.

METHODS

Twenty-three patients (21 men, 2 women; mean age 61.0±8.60 years) who were candidates for esophagectomy with conventional lymph node dissection for thoracic esophageal cancer were enrolled. A total dose of 1 mCi of 99mTc-MSA [technetium-99m neomannosyl human serum albumin] in 0.2 mL was administered at 4 quadrants into the submucosal layer around the primary tumor under esophagoscopic guidance approximately 1 hour before surgery. Intraoperative sentinel node sampling was subsequently followed by esophagectomy. All harvested lymph nodes were cut into 2-mm slices and ultimately diagnosed using formalin-fixed and paraffin-embedded sections with hematoxylin and eosin staining.

RESULTS

The number of dissected lymph nodes per patient was 30.5±9.18 (15-47). Among 23 patients, the sentinel lymph nodes could be identified in 21 patients (91.3%). The sentinel nodes could be identified in all 21 patients with cT1 or T2N0M0 (100%) disease; these patients were candidates for sentinel lymph node navigation surgery for the esophageal cancer. The mean number of sentinel nodes identified was 2.6±1.35 (range, 1-5) per patient. No false-negative sentinel lymph nodes were detected in any of the 8 patients with node-positive disease (0%).

CONCLUSIONS

Intraoperative sentinel lymph node identification using 99mTc-MSA was feasible and reliable in patients with esophageal squamous cell carcinoma.