How to avoid risks for patients in minimal-access trials: Avoiding complications in clinical first-in-human studies by example of the ADBEE study

Contained Power Morcellation in Laparoscopic Uterine Myoma Surgeries: A Brief Review

Uterine fibromas are the most common benign uterine tumors. Although the majority of leiomyomas remain asymptomatic, they can cause serious clinical problems, including abnormal uterine bleeding, pelvic pain, and infertility, which require effective gynecological intervention. Depending on the symptoms as well as patients' preferences, various treatment options are available, such as medical therapy, non-invasive procedures, and surgical methods. Regardless of the extent of the surgery, the preferred option is the laparoscopic approach. To reduce the risk of spreading occult malignancy and myometrial cells associated with fragmentation of the specimen before its removal from the peritoneal cavity, special systems for laparoscopic contained morcellation have been developed. The aim of this review is to present the state-of-the-art contained morcellation. Different types of available retrieval bags are demonstrated. The advantages and difficulties associated with contained morcellation are described. The impact of retrieval bag usage on the course of surgery, as well as the effects of the learning curve, are discussed. The role of contained morcellation in the overall strategy to optimize patient safety is highlighted.

The Future of Minimal-Access Myoma Surgery with In-Bag Contained Morcellation

Contained electromechanical morcellation has emerged as a safety approach for laparoscopic myomatous tissue retrieval. This retrospective single-center analysis evaluated the bag deployment practicability and safety of electromechanical in-bag morcellation when used for big surgical benign specimens. The main age of patients was 39.3 years (range 21 to 71); 804 myomectomies, 242 supracervical hysterectomies, 73 total hysterectomies, and 1 retroperitoneal tumor extirpation were performed. A total of 78.7% of specimens weighed more than 250 g (n = 881) and 9% more than 1000 g. The largest specimens, weighing 2933 g, 3183 g, and 4780 g, required two bags for complete morcellation. Neither difficulties nor complications related to bag manipulation were recorded. Small bag puncture was detected in two cases, but peritoneal washing cytology was free of debris. One retroperitoneal angioleiomyomatosis and three malignancies were detected in histology (leiomyosarcoma = 2; sarcoma = 1); therefore, patients underwent radical surgery. All patients were disease-free at 3 years follow-up, but one patient presented multiple abdominal metastases of the leiomyosarcoma in the third year; she refused subsequent surgery and was lost from follow-up. This large series demonstrates that laparoscopic bag morcellation is a safe and comfortable method to remove large and giant uterine tumors. Bag manipulation takes only a few minutes, and perforations rarely occur and are easy to detect intraoperatively. This technique did not result in the spread of debris during myoma surgery, potentially avoiding the additional risk of parasitic fibroma or peritoneal sarcoma.

Clinical feasibility of absorbable gelatin film adhesion barrier (GM142 "TENALEAF®") in gynecological laparoscopic surgery: Safety assessment for first-in-human use and surgical video

AIM

To evaluate the safety and operability of the GM142 (TENALEAF®, Medical Division, Gunze Limited, Tokyo, Japan) adhesion barrier applied in patients undergoing surgery for benign gynecologic disease.

METHODS

This multicenter open study enrolled 34 patients from November 2018 to October 2019.

RESULTS

The primary outcome was the incidence of adverse events (AE) within 12 weeks postoperatively. None of the 30 patients completing the study experienced a life-threatening AE. Thirteen patients (43.3%) suffered 30 mild or moderate AE in total. No intestinal obstruction (0/30) was observed, with the sample size justified by the AdSpray® trial (8/61 patients with AE). No gelatin-specific Immunoglobulin E (IgE) antibodies were induced in the patients. The adhesion barrier could be easily inserted (even via trocar) and positioned. After malfunctions were reported in six patients, the instructions for use were updated for trocar use.

CONCLUSION

This study showed the safety and clinical feasibility GM142 as an adhesion barrier.

Prevention of postoperative adhesion with a colloidal gel based on decyl group-modified Alaska pollock gelatin microparticles

Postoperative adhesion, bonding of the abdominal wall to damaged organs, causes severe complications after abdominal surgery. Despite the availability of physical barriers (i.e., solutions, films, and hydrogels), adhesion prevention materials that are a single-substance system with stability in wet tissue and ease of use have not been reported. Here, we report a microparticle based, sprayable adhesion prevention material comprising decyl group modified Alaska pollock gelatin (C10-ApGltn). C10-ApGltn microparticles (C10-MPs) were prepared by a coacervation method, freeze drying, and thermal crosslinking. The C10-MPs adhered to and formed a colloidal gel layer on intestinal serosal tissue by hydration without any crosslinking agents. After hydration of the C10-MPs, the resulting colloidal gel layer did not adhere to other tissues. Additionally, the C10-MP colloidal gel layer formed on the stomach serosal tissue showed stability when submersed in saline for 2 days. The colloidal gel layer also showed tissue followability. An in vivo rat adhesion model revealed that C10-MP colloidal gel layer on the cecum and abdominal wall defects effectively reduced postoperative adhesion and induced tissue remodeling, including re-mesothelialization. Therefore, C10-MPs are a potential anti-adhesion material for preventing postoperative adhesion. STATEMENT OF SIGNIFICANCE: We evaluated the postoperative adhesion prevention ability of a colloidal gel based on decyl group modified Alaska pollock gelatin (ApGltn) microparticles (C10-MPs). These microparticles are sprayable and form a colloidal gel with only hydration on the gastrointestinal tissue. We revealed that the modification of the decyl group into ApGltn improved the stability of C10-MP colloidal gel on the tissue by hydrophobic interaction in the in-vitro experiments. The gel prevented postoperative adhesion by being a physical barrier in the in-vivo rat adhesion model.

Advancement of Biomaterial-Based Postoperative Adhesion Barriers

Postoperative peritoneal adhesion (PPA) is a prevalent incidence that generally happens during the healing process of traumatized tissues. It causes multiple severe complications such as intestinal obstruction, chronic abdominal pain, and female infertility. To prevent PPA, several antiadhesion materials and drug delivery systems composed of biomaterials are used clinically, and clinical antiadhesive is one of the important applications nowadays. In addition to several commercially available materials, like film, spray, injectable hydrogel, powder, or solution type have been energetically studied based on natural and synthetic biomaterials such as alginate, hyaluronan, cellulose, starch, chondroitin sulfate, polyethylene glycol, polylactic acid, etc. Moreover, many kinds of animal adhesion models, such as cecum abrasion models and unitary horn models, are developed to evaluate new materials' efficacy. A new animal adhesion model based on hepatectomy and conventional animal adhesion models is recently developed and a new adhesion barrier by this new model is also developed. In summary, many kinds of materials and animal models are studied; thus, it is quite important to overview this field's current progress. Here, PPA is reviewed in terms of the species of biomaterials and animal models and several problems to be solved to develop better antiadhesion materials in the future are discussed.

Prevention of postoperative intrapericardial adhesion by dextrin hydrogel

OBJECTIVE

Postoperative intrapericardial adhesion increases the risk of complications in patients undergoing reoperation. We investigated the effect of a bioabsorbable dextrin hydrogel (DHG) on the formation of intrapericardial adhesions.

METHODS

Intrapericardial adhesion was surgically induced in Japanese white rabbits with DHG treatment (Adh + DHG) or without DHG treatment (Adh). The sham group was not treated with DHG and intrapericardial adhesion was not induced. The extent of intrapericardial adhesion was assessed by adhesion scoring and crystal violet staining of the pericardial cavity. Bromodeoxyuridine (BrdU) uptake assay was performed to assess the proliferative response to the injury in the tissue beneath the intrapericardial adhesion.

RESULTS

The Adh + DHG group showed looser intrapericardial adhesions compared to the Adh group. The adhesion area of the Adh + DHG group was 4.6 ± 2.2%, whereas that of the Adh group was 32.6 ± 6.4% at the end of the 28-day observation period (p < 0.01). The induction of intrapericardial adhesion resulted in a proliferative response mainly in the cardiac tissue just beneath the adhesion. There were 48.6 ± 10.7 cells/0.1 mm² BrdU-positive cells in the Adh + DHG group and 135.7 ± 23.8 cells/0.1 mm² BrdU-positive cells in the Adh group on day 28 (p < 0.05).

CONCLUSION

These findings indicate that DHG effectively prevented intrapericardial adhesion in this model.

Evaluation of adhesion barrier types in a rat hepatectomy-induced adhesion model

Background

Adhesion formation after hepatectomy creates problems for repeat hepatectomy. This study aimed to compare the effectiveness of a spray (AdSpray) and sheet adhesion barrier (Seprafilm) in a rat hepatectomy-induced adhesion model.

Methods

Thirty male Sprague-Dawley rats underwent partial resection of the left lateral liver lobe. They were randomly assigned to control (n = 10), AdSpray (n = 10), and Seprafilm groups. Seven days after surgery, the animals were sacrificed, and adhesions at the hepatic resection surface were blindly evaluated.

Results

In the control group, adhesions were formed in all 10 animals (100%), with a 69% adhesion extent (mean). In the AdSpray group, the incidence of adhesions (40%) and the adhesion extent (mean, 10%) were significantly lower than in the control group (incidence; p = 0.0147, adhesion extent; p = 0.0007). In the Seprafilm group, the incidence of adhesions was 70%. The adhesion extent of Seprafilm (mean, 30%) was significantly lower than in the control group (p = 0.0492). No significant differences were observed between the AdSpray and Seprafilm groups. As for histopathological examination, animals in the AdSpray group showed a similar healing profile to that of the control group without delayed healing and regeneration of mesothelial cells. In contrast, the Seprafilm group showed ongoing foreign body reaction to Seprafilm, and regeneration of mesothelial cells was immature at 7 days.

Conclusions

Both the spray-type gel and sheet adhesion barriers significantly reduced adhesion formation after hepatectomy. The spray-type adhesion barrier caused no adverse events and induced favorable healing. These adhesion barriers may be effective in hepatectomy. Further animal studies and clinical trials are required to determine their benefits in clinical use.

Laparoscopy or laparotomy as the way of entrance in myoma enucleation

PURPOSE

Uterine myomas are the main cause of benign uterine diseases in premenopausal women. Objective of the present paper is to investigate the current best treatment modalities of myomas, depending on age of the patient and her desire to preserve fertility, as well as on clinical presentation of this pathology, such as size, number, and location of fibroids and, furthermore, on surgical experience of the gynecologist.

METHODS

The design of our work is a systematic literature review of existing studies, reviews, and meta-analysis conducted in PubMed and Cochrane Library to identify relevant literature. Commonly, the myomectomy is to be recommended in women desiring to preserve fertility when myomas are associated with symptoms such as excessive bleeding, pelvic discomfort, or palpable abdominally fibroids. The decision of surgical approach for myomectomy should be individualized, depending on size and location, as well as on surgeon's experience. The different modalities of myomectomy, laparoscopic, hysteroscopic, robotic-assisted, or laparotomic are in detail presented in the paper, according to Society of Obstetricians and Gynecologists of Canada (SOGC) clinical practice guidelines and taking into consideration possible concerns of myomectomy such as uterine rupture, development of adhesions, and myomas' recurrence.

The Primary Result of Prospective Randomized Multicenter Trial of New Spray-Type Bio-absorbable Adhesion Barrier System (TCD-11091) Against Postoperative Adhesion Formation

BACKGROUND

Postoperative adhesions are the major cause of postoperative complications including intestinal obstruction, infertility, and chronic pelvic pain. In order to reduce postoperative adhesions, Terumo Corporation (Tokyo, Japan) has developed an adhesion barrier system (TCD-11091) which is easy to use at the treatment site in various surgical procedures including laparoscopic surgeries. We conducted a prospective randomized single-blind study in patients who underwent laparotomy with ileostomy.

METHODS AND RESULTS

One hundred twenty-six patients were randomly assigned to TCD-11091 group (n = 62) or non-treatment group (n = 62). Patient backgrounds were similar between the groups. At the time of ileostomy closure (the second-look surgery), the observation was performed on 55 in the TCD-11091 group and 43 in the control group. The incidence of adhesions observed at the second-look surgery was significantly lower in the TCD-11091 group (52.7 versus 90.7%; p < 0.001). For the secondary endpoints, the incidence of wide extent adhesions (grade 2 or higher) was significantly reduced (38.2 versus 79.1%; p < 0.001). Regarding the severity of adhesions, the incidence of grade 2 or higher adhesions was also significantly lower in the TCD-11091 group (47.3 versus 88.4%; p < 0.001). No differences in the incidence of adverse events were found between the TCD-11091 group and the non-treatment group (85.2 versus 75.4%; p = 0.225).

CONCLUSIONS

Use of TCD-11091 was safe and associated with significantly lower incidence of adhesion and severity of adhesions compared with non-treatment procedure.

Long term follow-up concerning safety and efficacy of novel adhesion prophylactic agent for laparoscopic myomectomy in the prospective randomized ADBEE study

We conducted a prospective randomized single blind - subject study in the University Clinic of Gynecology of Pius-Hospital Oldenburg. The primary objective of the ADBEE study was to assess the safety and manageability of ADBLOCK when used as an adjunct to laparoscopic surgery for the primary of myomas in women wishing to improve pregnancy outcomes. The study population included 32 women aged between 18-45 years, in good general health condition, who have not completed their family planning and who are undergoing primary ('virgin') laparoscopic myomectomy with an aim to improve pregnancy outcomes. The patients were randomized in 2 groups, ADBLOCK arm with 21 patients and surgery only arm with 11 patients. The study was single blind - subject and the investigators were blinded to treatment group assignment until completion of uterine suturing and prior to removal of the endoscope. A vigorous follow-up of subjects was organized, focusing on its two critical characteristics: completeness and duration. Completeness represented the percentage of subjects who returned to every planed follow - up appointments. The patients were evaluated in a specific period of time, which defined the duration of follow-up. Safety of the ADBLOCK was estimated after analyzing and documentation of any adverse events occurred, clinical and physical examination of patients as well as evaluation of laboratory measures. There were 25 adverse events reported in ADBLOCK treatment group and 12 events in NO-ADBLOCK group over the 24-months treatment. All adverse events in both treatment arms were not anticipated, with all events in the ADBLOCK group being resolved. At 28 days, there was no significant difference in proportion of events between the two treatments (p = 0.440). Overall, the number of events reported was low and the severity of events was generally mild with an unlikely or no relationship to treatment. There were no unanticipated device related adverse events seen in both treatment groups over the immediate post-operative period or during the 24 months follow up period. By 12 weeks all patients reported their wound as healing well or healed and at 6 months all wounds were reported as healed. There were no differences between both treatment groups regarding the use of painkillers over 24 months follow up period. This clinical first - in - human study, sustained by a rigorous follow-up of the subjects has demonstrated that ADBLOCK is a safe product, presenting no additional safety risk or burden to the patients over surgery alone. The device was relatively easy to use, with a low device failure rate that had no impact on the surgical procedures.