Efficacy of surgical resection and ultra-reduced tension suture combined with superficial radiation in keloid treatment

BACKGROUND

There are many available treatment options for keloid; however, single treatments are usually less effective. Therefore, more scientifically rational and effective combined treatment methods should be sought to solve the pain associated with keloids.

AIM

To explore the efficacy and safety of surgical resection and ultra-reduced tension suture combined with superficial radiation as keloid treatment.

METHODS

Fifteen keloid patients admitted to Qingdao Eighth People's Hospital from June 2020 to January 2022 were enrolled in this retrospective analysis. All patients underwent a comprehensive treatment approach comprising surgical resection, ultra-reduced tension suture incision, and superficial radiation therapy within 24 h postoperatively. The modified Vancouver Scar Scale (mVSS) and Patient and Observer Scar Assessment Scale (POSAS) were used to evaluate the treatment effect, whereas the efficacy, adverse effects, and recurrence rate were observed according to the 12-mo follow-up after treatment.

RESULTS

The mVSS and POSAS scores at 1 and 6 mo after combination treatment decreased compared to before treatment (P < 0.001), and the overall response rate was 93.3%. Only one case recurred, yielding a 6.7% recurrence rate. The incidence of local chromour sedimentation rate in 1-3 mo after radiotherapy was 33.3% (5 patients), all subsiding after 6-9 mo, without complications, such as delayed wound healing or dermatitis.

CONCLUSION

Surgical resection, super subtraction sutures, and superficial radiotherapy are treatment methods with short courses, low recurrence rates, and good safety profiles.

Synthesis of 225Ac-PSMA-617 for preclinical use

BACKGROUND

The recent approval of radiopharmaceuticals for diagnosis and treatment of cancer is ushering nuclear medicine into a new era of theranostics, and alpha therapy using radiopharmaceuticals labeled with ²²⁵Ac is showing remarkable results in clinical trials. As such, reliable methods for the synthesis and quality control of ²²⁵Ac-radiopharmaceuticals are needed.

OBJECTIVE

²²⁵Ac-PSMA-617 is being used for targeted alpha therapy in patients with prostate cancer, and we aimed to synthesize the agent for preclinical use. However, technology transfer proved cumbersome owing to the paucity of information available on synthesizing and analyzing ²²⁵Ac-radiotherapeutics. To address this need, we describe a straightforward synthesis of ²²⁵Ac-PSMA-617 as well as suitable approaches for quality control analysis using standard equipment in a modern PET Center.

METHODS

PSMA-617 precursor was dissolved in 25 μL metal-free water (0.67 mg/mL), and combined with 500 μL 0.05M Tris buffer, pH 9. Actinium stock solution (~65 μCi in 15 µL) was added and the reaction was heated at 120˚C for 40-50 min. The reaction was cooled and 0.6 mL gentisic acid solution (4 mg/mL in 0.2 M NH₄OAc) was added. To formulate the dose for injection, sterile saline, USP (8 mL) was added and the pH was adjusted by addition of 100 μL 0.05 M Tris buffer (pH 9) to achieve a final pH of ~7.2. The final solution was filtered using a 0.22 µm GV sterile filter into a sterile dose vial. Radiochemical purity was determined by radio-TLC (eluent: 50mM Sodium Citrate, pH 5) and plates were analyzed using an AR2000 scanner.

RESULTS

The method provided ²²⁵Ac-PSMA-617 in high radiochemical yield (57 ± 3 µCi, >99%) and radiochemical purity (98 ± 1%), formulated for preclinical studies (9 mL, pH = 7.2), n=3.

CONCLUSION

A straightforward synthesis of ²²⁵Ac-PSMA-617 is described that will facilitate production for (pre)clinical studies. The approach could also be applicable to the synthesis of other alpha radiotherapeutics incorporating ²²⁵Ac.

[Discussion on the mechanism of anal sphincter insufficiency caused by radiotherapy in patients with rectal cancer]

At present, radiotherapy as an auxiliary treatment for rectal cancer is widely used in clinic. Although radiotherapy has significant effect on reducing tumor stage, improving anus preservation rate and less tumor recurrence, radiotherapy will damage the anal function and seriously affect the quality of life of patients. Anal sphincter plays an important role in anal function. There are three main damage effects of radiotherapy on anal sphincter: first, the increased deposition of collagen in internal anal sphincter (IAS); second, the destroyed ultrastructure of external anal sphincter (EAS); third, degenerative lesions of the perianal nerve. This article reviews these three points, in order to provide a certain theoretical basis for how to reduce the incidence of anal dysfunction caused by radiotherapy.