Intraoperative image-guided surgery for ovarian cancer

Hyperspectral Imaging for Tissue Classification after Advanced Stage Ovarian Cancer Surgery-A Pilot Study

The most important prognostic factor for the survival of advanced-stage epithelial ovarian cancer (EOC) is the completeness of cytoreductive surgery (CRS). Therefore, an intraoperative technique to detect microscopic tumors would be of great value. The aim of this pilot study is to assess the feasibility of near-infrared hyperspectral imaging (HSI) for EOC detection in ex vivo tissue samples. Images were collected during CRS in 11 patients in the wavelength range of 665−975 nm, and processed by calibration, normalization, and noise filtering. A linear support vector machine (SVM) was employed to classify healthy and tumorous tissue (defined as >50% tumor cells). Classifier performance was evaluated using leave-one-out cross-validation. Images of 26 tissue samples from 10 patients were included, containing 26,446 data points that were matched to histopathology. Tumorous tissue could be classified with an area under the curve of 0.83, a sensitivity of 0.81, a specificity of 0.70, and Matthew’s correlation coefficient of 0.41. This study paves the way to in vivo and intraoperative use of HSI during CRS. Hyperspectral imaging can scan a whole tissue surface in a fast and non-contact way. Our pilot study demonstrates that HSI and SVM learning can be used to discriminate EOC from surrounding tissue.

Dual-labeled pertuzumab for multimodality image-guided ovarian tumor resection

Pertuzumab is clinically employed in the treatment of cancers over-expressing human epidermal growth factor receptor 2 (HER2). Herein, we developed dual-labeled pertuzumab with a radionuclide (⁸⁹Zr) and a near-infrared fluorophore (IRDye 800CW) to investigate the feasibility of utilizing dual-labeled monoclonal antibodies (mAbs) with numerous imaging modalities for preoperative imaging and image-guided surgery in ovarian cancer models. MAbs were dually-labeled with ⁸⁹Zr and IRDye 800CW to generate ⁸⁹Zr-Df-pertuzumab-800CW or ⁸⁹Zr-Df-IgG-800CW. Serial positron emission tomography (PET) and near-infrared fluorescence (NIRF) images were acquired up to 72 hours after injection of dual-labeled mAbs to map the tracers' biodistributions. After the last time point, image-guided tumor resection was executed using different modalities (NIRF, Cerenkov luminescence [CL], and β particle imaging) and ex vivo studies including biodistribution assays and histology analysis were performed to confirm the in vivo imaging data. SKOV3 ovarian cancer cells showed high expression of HER2 and pertuzumab conjugated with Df and IRDye 800CW maintained its binding affinity for these cells. For PET imaging in subcutaneous xenograft ovarian cancer models, ⁸⁹Zr-Df-pertuzumab-800CW showed a significantly higher tumor-to-muscle ratio compared to the nonspecific ⁸⁹Zr-Df-IgG-800CW from 24 hours after injection through the last time point (72 h: 30.7 ± 7.4 vs. 7.5 ± 1.8, P < 0.01, n = 3-4). During image-guided surgery, three imaging modalities including NIRF, CL, and β particle imaging could detect ovarian cancer in both subcutaneous and orthotopic models and each exhibited its own imaging characteristics. In addition, ex vivo imaging and biodistribution studies as well as histology analysis corroborated the in vivo imaging results. Therefore, we concluded that this single radiolabeled tracer can provide all-in-one contrast for multiple imaging modalities. The dual-labeled mAbs may hold promise to be employed for image-guided tumor surgery as well as diagnosis and staging through balancing out the strengths and weaknesses of various modalities such as PET/CT, NIRF, CL, and β particle imaging.

Improved Debulking of Peritoneal Tumor Implants by Near-Infrared Fluorescent Nanobody Image Guidance in an Experimental Mouse Model

PURPOSE

Debulking followed by combination chemotherapy is currently regarded as the most effective treatment for advanced ovarian cancer. Prognosis depends drastically on the degree of debulking. Accordingly, near-infrared (NIR) fluorescence imaging has been proposed to revolutionize cancer surgery by acting as a sensitive, specific, and real-time tool enabling visualization of cancer lesions. We have previously developed a NIR-labeled nanobody that allows fast, specific, and high-contrast imaging of HER2-positive tumors. In this study, we applied this tracer during fluorescence-guided surgery in a mouse model and investigated the effect on surgical efficiency.

PROCEDURES

0.5 × 10⁶ SKOV3.IP1-Luc+ cells were inoculated intraperitoneally in athymic mice and were allowed to grow for 30 days. Two nanomoles of IRDye800CW-anti-HER2 nanobody was injected intravenously. After 1h30, mice were killed, randomized in two groups, and subjected to surgery. In the first animal group (n = 7), lesions were removed by a conventional surgical protocol, followed by excision of remaining fluorescent tissue using a NIR camera. The second group of mice (n = 6) underwent directly fluorescence-guided surgery. Bioluminescence imaging was performed before and after surgery. Resected tissue was categorized as visualized during conventional surgery or not, fluorescent or not, and bioluminescent positive or negative.

RESULTS

Fluorescence imaging allowed clear visualization of tumor nodules within the abdomen, up to submillimeter-sized lesions. Fluorescence guidance resulted in significantly reduced residual tumor as compared to conventional surgery. Moreover, sensitivity increased from 59.3 to 99.0 %, and the percentage of false positive lesions detected decreased from 19.6 to 7.1 %.

CONCLUSIONS

This study demonstrates the advantage of intraoperative fluorescence imaging using nanobody-based tracers on the efficiency of debulking surgery.

Survival outcomes after extensive cytoreductive surgery and selective neoadjuvant chemotherapy according to institutional criteria in bulky stage IIIC and IV epithelial ovarian cancer

Objective

To investigate the survival outcomes in patients with bulky stage IIIC and IV ovarian cancer, treated by primary debulking surgery (PDS) and selective use of neoadjuvant chemotherapy (NAC) according to institutional criteria.

Methods

Medical records for advanced ovarian cancer patients who were treated at National Cancer Center (NCC) between December 2000 and March 2009 were retrospectively reviewed in the comprehensive cancer center. Bulky stage IIIC and IV ovarian cancer cases were included. Current NCC indication for NAC is determined based on patients' performance status and/or computerized tomography (CT) findings indicating difficult cytoreduction. After NAC, all traces of regressed metastatic ovarian cancer, potentially including chemotherapy-resistant cancer cells, were surgically removed.

Results

Of the 279 patients with bulky stage IIIC and IV, 143 (51%) underwent PDS and 136 (49%) received NAC. No gross residual and residual tumor measuring ≤1 cm was achieved in 66% and 96% of the PDS group and 79% and 96% of the NAC group, respectively. The median progression-free survival (PFS) and overall survival (OS) time were 20 months and not reached, but might be estimated more than 70 months in the PDS group and 15 and 70 months in the NAC group, respectively.

Conclusion

Extensive cytoreductive surgery to minimize residual tumor and selective use of NAC based on the institutional criteria could result in improved survival outcomes. Until further studies can be done to define the selection criteria for NAC after surgery, institutional criteria for NAC should consider the ability of the surgeon and institutional capacity.

Antigen-responsive molecular sensor enables real-time tumor-specific imaging

Antibody-fluorophore conjugates have high potential for the specific fluorescence detection of target cancer cells in vitro and in vivo. However, the antibody-fluorophore conjugates described to date are inappropriate for real-time imaging of target cells because removal of unbound antibody is required to reduce background fluorescence before quantifiable analysis by microscopy. In addition, clinical applications of the conjugates have been limited by persistent background retention due to their long systemic circulation and nonspecific uptake. Here we report fast and real-time near-infrared fluorescence imaging of target cancer cells using an antigen-responsive molecular “on-off” sensor: the fluorescence of trastuzumab-ATTO680 conjugate is dark (i.e., turned off) in the extracellular region, while it becomes highly fluorescent (i.e., turned on) upon binding to the target antigen HER2 on cancer cell surface. This molecular switch enables fast and real-time imaging of target cancer cells in vitro and in vivo.

Improved Postoperative Pain Control for Cytoreductive Surgery in Women With Ovarian Cancer Using Patient-Controlled Epidural Analgesia

OBJECTIVE

Many studies have compared different methods of postoperative pain management in abdominal laparotomy patients; however, the conclusions have been inconsistent and controversial. This study aimed to compare the pain scores and complications of patients who underwent cytoreductive surgery for ovarian cancer and used either patient-controlled epidural analgesia (PCEA) or patient-controlled intravenous analgesia (PCA) for postoperative pain management. We hypothesized that PCEA would be superior to PCA for postoperative pain management in ovarian cancer surgery.

MATERIALS AND METHODS

The medical records of women who underwent ovarian cancer surgery in 2014 were reviewed retrospectively. Pain scores for postoperative days (PODs) 0 to 5 days and the incidence of complications were examined and compared in patients who received PCEA and PCA. Means were compared using an independent sample t test or Wilcoxon rank sum test, and proportions were compared using Fisher exact test or a χ(2) test at each time point. A mixed-effects model was applied to determine correlations among repeated measurements. A P value less than 0.05 was considered significant.

RESULTS

Of the 105 study patients, 38 received PCEA and 67 received PCA. Pain scores were significantly lower in the PCEA group than the PCA group at POD 0 (2.47 ± 1.75 vs 4.39 ± 1.17; P < 0.001), 1 (2.65 ± 1.02 vs 3.32 ± 1.09; P < 0.001), and 3 (2.17 ± 1.13 vs 2.79 ± 1.08; P = 0.011), and tended to be lower in the PCEA group at PODs 2, 4, and 5. Patient-controlled epidural analgesia provided significantly better pain relief as analyzed by a mixed-effect model. Complications were not significantly different between both groups. There was no significant difference in pain relief between both groups at PODs 4 and 5.

CONCLUSIONS

Patient-controlled epidural analgesia was more effective for postoperative pain management compared with PCA from POD 0 to POD 3 in patients with ovarian cancer who underwent cytoreductive surgery, without increasing the morbidity.

Exponential growth of publications on carbon nanodots by Chinese authors

Publication statistics was retrieved on carbon nanodots (C-dots) from 2004 up till 2014 using the web of Science(TM) search engine. The number of publications from Chinese authors increased exponentially during this period. Till 2014 China mainland authors contributed 47% of the total publications. Publications on pharmacology and toxicology lagged far behind the publications on chemistry and material science, indicating that research is not solidly moving toward the direction of application.

Quality of life and sexuality comparison between sexually active ovarian cancer survivors and healthy women

Objective

compare quality of life (QoL) and sexual functioning between sexually active ovarian cancer survivors and healthy women.

Methods

A cross-sectional study was performed in 103 successfully treated ovarian cancer survivors and 220 healthy women. All women had engaged in sexual activity within the previous 3 months, and ovarian cancer survivors were under surveillance after primary treatment without evidence of disease. QoL and sexual functioning were assessed using three questionnaires; the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), Ovarian Cancer Module (EORTC QLQ-OV28), and the Female Sexual Function Index (FSFI). Propensity score matching was used to adjust covariates between the ovarian cancer survivor and healthy women groups. In total, 73 ovarian cancer survivors and 73 healthy women were compared.

Results

Poorer social functioning (mean, 82.4 vs. 90.9; p=0.010) and more financial difficulties (mean, 16.4 vs. 7.8; p=0.019) were observed among ovarian cancer survivors than among healthy women. Sexuality, both in terms of desire, arousal, lubrication, orgasm, satisfaction, and pain and in terms of interest in sex, sexual activity, and enjoyment of sex (EORTC QLQ-OV28) were similar between the groups. However, vaginal dryness was more problematic in ovarian cancer survivors, with borderline statistical significance (p=0.081).

Conclusion

Sexuality was not impaired in ovarian cancer survivors who were without evidence of disease after primary treatment and having sexual activities, compared with healthy women, whereas social functioning and financial status did deteriorate. Prospective cohort studies are needed.

Near infrared fluorescence for image-guided surgery

Near infrared (NIR) image-guided surgery holds great promise for improved surgical outcomes. A number of NIR image-guided surgical systems are currently in preclinical and clinical development with a few approved for limited clinical use. In order to wield the full power of NIR image-guided surgery, clinically available tissue and disease specific NIR fluorophores with high signal to background ratio are necessary. In the current review, the status of NIR image-guided surgery is discussed along with the desired chemical and biological properties of NIR fluorophores. Lastly, tissue and disease targeting strategies for NIR fluorophores are reviewed.