Organic Nanoparticles Based on D-A-D Small Molecule: Self-Assembly, Photophysical Properties, and Synergistic Photodynamic/Photothermal Effects

Cancer is one of the major diseases threatening human health. Traditional cancer treatments have notable side-effects as they can damage the immune system. Recently, phototherapy, as a potential strategy for clinical cancer therapy, has received wide attention due to its minimal invasiveness and high efficiency. Herein, a small organic molecule (PTA) with a D-A-D structure was prepared via a Sonogashira coupling reaction between the electron-withdrawing dibromo-perylenediimide and electron-donating 4-ethynyl-N,N-diphenylaniline. The amphiphilic organic molecule was then transformed into nanoparticles (PTA-NPs) through the self-assembling method. Upon laser irradiation at 635 nm, PTA-NPs displayed a high photothermal conversion efficiency (PCE = 43%) together with efficient reactive oxygen species (ROS) generation. The fluorescence images also indicated the production of ROS in cancer cells with PTA-NPs. In addition, the biocompatibility and photocytotoxicity of PTA-NPs were evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and live/dead cell co-staining test. Therefore, the as-prepared organic nanomaterials were demonstrated as promising nanomaterials for cancer phototherapy in the clinic.

Combinatorial Therapeutic Approaches with Nanomaterial-Based Photodynamic Cancer Therapy

Photodynamic therapy (PDT), in which a light source is used in combination with a photosensitizer to induce local cell death, has shown great promise in therapeutically targeting primary tumors with negligible toxicity and minimal invasiveness. However, numerous studies have shown that noninvasive PDT alone is not sufficient to completely ablate tumors in deep tissues, due to its inherent shortcomings. Therefore, depending on the characteristics and type of tumor, PDT can be combined with surgery, radiotherapy, immunomodulators, chemotherapy, and/or targeted therapy, preferably in a patient-tailored manner. Nanoparticles are attractive delivery vehicles that can overcome the shortcomings of traditional photosensitizers, as well as enable the codelivery of multiple therapeutic drugs in a spatiotemporally controlled manner. Nanotechnology-based combination strategies have provided inspiration to improve the anticancer effects of PDT. Here, we briefly introduce the mechanism of PDT and summarize the photosensitizers that have been tested preclinically for various cancer types and clinically approved for cancer treatment. Moreover, we discuss the current challenges facing the combination of PDT and multiple cancer treatment options, and we highlight the opportunities of nanoparticle-based PDT in cancer therapies.

Weakening or Structural Strengthening? An Evaluation of Bone Density after MRgFUS Ablation for Treatment of Benign Bone Lesions

Previous studies suggest that interventional ablative procedures on bone lesions may weaken the bone, especially when performed through the needle approach. Our purpose was to evaluate, through Computed Tomography (CT), the effects of Magnetic Resonance guided Focused Ultrasound Surgery (MRgFUS) ablation on painful osteoid osteomas and osteoblastomas in terms of bone density and morphological changes. We retrospectively evaluated patients treated at our institution with MRgFUS for superficial, painful osteoid osteoma or osteoblastoma during the last 9 years. Inclusion criteria were procedural and clinical success, as well as the availability of pre- and postprocedural CT examinations. Imaging features assessed were perilesional/nidus density changes and the occurrence of pathological fractures during the follow-up period. Our study population included 31 osteoid osteomas and 5 intra-articular osteoblastomas in 36 treated patients. We found an increased bone density of the lesions when pre and post-treatment CT- values were compared: these differences were statistically significant, and this finding is consistent with significant bone densification at the post-treatment imaging follow-up. No pathological fractures were observed after ablation during the follow-up. MRgFUS can be considered to be the treatment of choice for benign superficial bone lesions, thanks to its minimal invasiveness, excellent effectiveness, and safety. Pathological fractures, reported in literature as a rare event using needle ablation, never occurred in our MRgFUS treatment series.

Endoscopic Delivery Method Using a Retrieval Net for Patients with Small-Bowel Capsule Endoscopy Stagnation in the Stomach

With the increasing use of capsule endoscopy (CE), screening tests for the small bowel can be performed with minimal invasiveness. However, occasionally, the entire small bowel cannot be observed because of decreased peristalsis of the stomach. For such cases, we perform delivery of CE by an endoscope. We retrospectively examined the usefulness of the endoscopic delivery method using a retrieval net for patients with CE stagnation in the stomach. From 2,270 patients who underwent small-bowel CE at Hiroshima University Hospital from January 2013 to January 2020, 29 consecutive patients (1.3% of the total number) in whom the small bowel could not be observed due to CE stagnation in the stomach at the time of the initial CE underwent the endoscopic delivery method using a retrieval net for secondary small-bowel CE. This study included 16 male (55%) and 13 female (45%) patients with a mean age of 69.2 ± 13.2 years . 11 patients (38%) had a history of gastrointestinal surgical resection. The entire small bowel could be observed in 19 patients (66%), and CE reached the terminal ileum in the remaining patients. A history of gastrointestinal surgical resection was significantly more frequent in the group where the entire small bowel could not be observed. The rate of small-bowel lesion detection was 55% (16/29). There were no adverse events associated with our endoscopic delivery method. Thus, the endoscopic delivery method using a retrieval net for patients with initial CE stagnation in the stomach may be safe and useful for the detection of small-bowel lesions.

The first experience of ultrasound-guided percutaneous microwave ablation for extracranial schwannoma of the cervical vagus nerve in carotid space and treatment response evaluation with contrast-enhanced imaging

Schwannoma is a benign tumor that originates from Schwann cells in the nerve sheathing of cranial, other peripheral, or autonomic nerves. Patients often present with painless mass as the chief complaint. The main symptoms of this tumor are related to its size and specific nerve origin. At present, the pretreatment diagnosis is mainly made by ultrasound, CT, MR, or biopsy, and the main treatment is surgical resection. We reported a new treatment method for cervical schwannoma in a 65-year-old woman with a history of non-small cell lung cancer (NSCLC). When the patient’s neck mass was initially found with hoarseness and severe cough, it was considered as cervical lymph node metastasis of lung cancer due to her medical history. And she was diagnosed with schwannoma by core-needle biopsy after chemotherapy failed and the tumor shrank after the radiotherapy with no improvement of the clinical symptoms. After considering the physical condition, the patients were treated in our department for minimal invasiveness treatment. The patient was definitively diagnosed with cervical vagus schwannoma and was treated with ultrasound-guided microwave ablation of schwannoma under general anesthesia with systematic evaluation and improved preoperative examination. Her condition was stable, and the symptoms of severe cough disappeared after anesthesia resuscitation and the ablation. The tumor continued to shrink after the operation with no recurrence of cough symptoms. Ultrasound-guided percutaneous microwave ablation (MWA) for cervical vagus schwannomas might be a minimally invasive, effective, and relatively safe alternative to conventional treatment for those patients with severe symptoms.

In Situ-Forming Cellulose/Albumin-Based Injectable Hydrogels for Localized Antitumor Therapy

Injectable hydrogels, which are formed in situ by changing the external stimuli, have the unique characteristics of easy handling and minimal invasiveness, thus providing the advantage of bypass surgical operation and improving patient compliance. Using external temperature stimuli to realize the sol-to-gel transition when preparing injectable hydrogel is essential since the temperature is stable in vivo and controllable during ex vivo, although the hydrogels obtained possibly have low mechanical strength and stability. In this work, we designed an in situ fast-forming injectable cellulose/albumin-based hydrogel (HPC-g-AA/BSA hydrogels) that responded to body temperature and which was a well-stabilized hydrogen-bonding network, effectively solving the problem of poor mechanical properties. The application of localized delivery of chemotherapeutic drugs of HPC-g-AA/BSA hydrogels was evaluated. In vitro and in vivo results show that HPC-g-AA/BSA hydrogels exhibited higher antitumor efficacy of reducing tumor size and seem ideal for localized antitumor therapy.

The Use of High-Intensity Focused Ultrasound (HIFU) Plus 150mg Bicalutamide as First Line Salvage Therapy for Local Recurrent Prostate Cancer

Patients with localized prostate cancer (PCa) are often treated with radical prostatectomy (RP). However, more than 30% of such patients have high risk of recurrence. Salvage radiotherapy (SRT), androgen deprivation therapy (ADT) and combination of radiotherapy and ADT are the standard care for recurrent PCa. Recently, high intensity focused ultrasound (HIFU) has gradually applied in the treatment of recurrent PCa. Here, we proposed a hypothesis that combined HIFU and bicalutamide 150mg as first line salvage therapy to treat patients with local recurrent PCa with visible lesions due to the following advantages: (1) HIFU is effective in reducing local tumor load, and bicalutamide 150mg is a feasible and safety option to combine with HIFU. (2) Compared with radiotherapy, HIFU plus 150mg bicalutamide is minimal invasiveness with fewer adverse effects and better quality of life(QOL); (3) Radiotherapy can be preserved as the second-line salvage method in the cases who are failure to HIFU and 150mg bicalutamide combination. More clinical trials are warranted to confirm this hypothesis in treatment with recurrent PCa.

Laser Ablation Treatment of Recurrent Lymph Node Metastases from Papillary Thyroid Carcinoma

(1) Background: The incidence of papillary thyroid cancers is increasing. Papillary neoplasm metastasizes to the central and lateral lymph nodes of the neck. The recurrence rate is less than 30%. The gold standard of treatment for lymph node recurrences is surgery, but surgery is burdened by a high rate of complications. Therefore, laser ablation of recurrent lymph nodes has been recognized as an alternative treatment with minimal invasiveness, a low complication rate and a curative effect. (2) Methods: We analyzed 10 patients who underwent a total thyroidectomy and metabolic radiotherapy and who developed a lymph node recurrence in the laterocervical compartment in the following 12–18 months. (3) Results: Patients developed lymph node recurrence at IV and Vb levels in 70% and 30% of cases, respectively. All patients were treated with a single laser ablative session. Hydrodissection was performed in all patients. The energy delivered was 1120 ± 159.3 Joules and 3–4 Watts in 362 ± 45.7 s. No complications were reported. All patients underwent a 6-month follow-up. A volumetric reduction of 40.12 ± 2.2%, 49.1 ± 2.13% and 59.8 ± 3.05%, respectively at 1-, 3- and 6-months of follow-up was reported. (4) Conclusions: At 6 months, a fine needle aspiration was performed, which was negative for malignant cells and negative for a dosage of Thyroglobulin in eluate. The laser ablation is an effective alternative to surgical treatment.

Progression of Prothrombin Induced by Vitamin K Absence-II in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer-related death worldwide. Due to the lack of efficient tools for early detection, asymptomatic HCC patients are diagnosed at an advanced stage, leading to a poor prognosis. To improve survival, serum biomarker prothrombin induced by vitamin K absence-II (PIVKA-II) was under investigation. PIVKA-II is an abnormal protein produced in HCC. The coagulation function was insufficient due to the lack of Gla residues. Elevated PIVKA-II was associated with bad tumor behavior in terms of proliferation, metastasis, and invasion. Three major signaling pathways were proposed to clarify the mechanism. With the advantages including affordability, minimal invasiveness, convenience, and efficiency, PIVKA-II could improve HCC management consisting of four aspects. First, PIVKA-II was an effective and dynamic tool for improving HCC surveillance in high-risk population. Changes in the serum levels of PIVKA-II provided valuable molecular alteration information before imaging discovery. Second, PIVKA-II offered a complementary approach for HCC early detection. Compared to traditional diagnostic approaches, the combination of PIVKA-II and other biomarkers had better performance. Third, PIVKA-II was an indicator for the assessment of response to treatment in HCC. Preoperative assessment was for selecting personalized therapy, and postoperative measurement was for assessing treatment efficacy. Fourth, PIVKA-II was considered as a prognostic predictor for HCC. Patients with elevated PIVKA-II were more likely to develop microvascular invasion, metastasis, and recurrence.

P125 MANAGEMENT OF PERICAECAL HERNIA CAUSING SMALL BOWEL OBSTRUCTION IN THE EVOLVING ERA OF LAPAROSCOPY. A CASE REPORT AND LITERATURE REVIEW

Introduction “Internal hernias are an unusual cause of intestinal obstruction. Pericaecal hernias are an exceptionally rare type of internal hernia. Laparoscopy for small bowel obstruction was previously considered inappropriate. We present a case of Pericaecal hernia causing small bowel obstruction treated successfully with a laparoscopic approach.” Case-Report “64 year old man presented with abdominal pain, vomiting and constipation for 3 days, no previous surgery. Small bowel obstruction confirmed on PFA and CT. He was treated conservatively for 10 days without settling. A an exploratory laparoscopy revealed a Pericaecal hernia. This was reduced with gentle manoeuvre and the peritoneal folds were divided to prevent recurrence. Recovery was uneventful.” Discussion “Perioperative diagnosis of internal hernia is extremely difficult. Pericaecal hernia is an uncommon type of internal hernia. CT diagnosis of internal hernia remains difficult. Laparoscopy is a valuable tool for diagnosis and treatment with the advantage of minimal invasiveness. However, the laparoscopic manipulation of distended bowel loops remain controversial because of high risk of perforation, reduced space to work in the peritoneal cavity and requirement of advanced laparoscopic skills. Laparoscopic treatment of Pericaecal hernia was reported about 17 years ago but has since been reported more frequently and in recent years there is a move towards laparoscopic diagnosis and management of Pericaecal hernias.” Conclusions “CT diagnosis of internal hernia remains difficult. With the advent of minimal access surgery, diagnostic laparoscopy may be a safe and feasible modality to diagnose and deliver definitive treatment of small bowel obstruction secondary to Pericaecal hernia.”