Preoperative prediction of malignant potential of 2-5 cm gastric gastrointestinal stromal tumors by computerized tomography-based radiomics

BACKGROUND

The use of endoscopic surgery for treating gastrointestinal stromal tumors (GISTs) between 2 and 5 cm remains controversial considering the potential risk of metastasis and recurrence. Also, surgeons are facing great difficulties and challenges in assessing the malignant potential of 2-5 cm gastric GISTs.

AIM

To develop and evaluate computerized tomography (CT)-based radiomics for predicting the malignant potential of primary 2-5 cm gastric GISTs.

METHODS

A total of 103 patients with pathologically confirmed gastric GISTs between 2 and 5 cm were enrolled. The malignant potential was categorized into low grade and high grade according to postoperative pathology results. Preoperative CT images were reviewed by two radiologists. A radiological model was constructed by CT findings and clinical characteristics using logistic regression. Radiomic features were extracted from preoperative contrast-enhanced CT images in the arterial phase. The XGboost method was used to construct a radiomics model for the prediction of malignant potential. Nomogram was established by combing the radiomics score with CT findings. All of the models were developed in a training group (n = 69) and evaluated in a test group (n = 34).

RESULTS

The area under the curve (AUC) value of the radiological, radiomics, and nomogram models was 0.753 (95% confidence interval [CI]: 0.597-0.909), 0.919 (95%CI: 0.828-1.000), and 0.916 (95%CI: 0.801-1.000) in the training group vs 0.642 (95%CI: 0.379-0.870), 0.881 (95%CI: 0.772-0.990), and 0.894 (95%CI: 0.773-1.000) in the test group, respectively. The AUC of the nomogram model was significantly larger than that of the radiological model in both the training group (Z = 2.795, P = 0.0052) and test group (Z = 2.785, P = 0.0054). The decision curve of analysis showed that the nomogram model produced increased benefit across the entire risk threshold range.

CONCLUSION

Radiomics may be an effective tool to predict the malignant potential of 2-5 cm gastric GISTs and assist preoperative clinical decision making.

Development of a novel rat model of heterogeneous hepatic injury by injection with colchicine via the splenic vein

AIM

To develop a novel rat model of heterogeneous hepatic injury.

METHODS

Seventy male Sprague-Dawley rats were randomly divided into a control group (n = 10) and a colchicine group (n = 60). A 0.25% colchicine solution (0.4 mL/kg) was injected via the splenic vein in the colchicine group to develop a rat model of heterogeneous hepatic injury. An equal volume of normal saline was injected via the splenic vein in the control group. At days 3, 7, and 14 and weeks 4, 8, and 12 after the operation, at least seven rats of the colchicine group were selected randomly for magnetic resonance imaging (MRI) examinations, and then they were euthanized. Ten rats of the control group underwent MRI examinations at the same time points, and then were euthanized at week 12. T2-weighted images (T2WI) and diffusion weighted imaging (DWI) were used to evaluate the heterogeneous hepatic injury. The heterogeneous injury between the left and right hepatic lobes was assessed on liver sections according to the histological scoring criteria, and correlated with the results of MRI study.

RESULTS

Obvious pathological changes occurred in the hepatic parenchyma in the colchicine group. Hepatic injury scores were significantly different between the left and right lobes at each time point (P < 0.05). There was a significant difference in apparent diffusion coefficient (ADC) of DWI and liver-to-muscle ratio (LMR) of T2WI between the left and right lobes of rats in the colchicine group (P < 0.05) at each time point, and similar results were observed between the colchicine and control groups. Besides, there was a significant correlation between hepatic injury scores and ADC values or LMR (r = -0.682, P = 0.000; r = -0.245, P = 0.018).

CONCLUSION

Injection with colchicine via the splenic vein can be used to successfully develop a rat model of heterogeneous hepatic injury. DWI and T2WI may help evaluate the heterogeneous injury among liver lobes.

[The treatment of partial CO₂ laser arytenoidectomy for bilateral vocal fold paralysis]

Objective:To assess the efficacy of partial CO₂ laser arytenoidectomy in cases with bilateral vocal fold paralysis. Method:A total number of 11 patients with bilateral vocal fold paralysis who undergone partial CO₂ laser arytenoidectomy was included in this retrospective study. The efficacy of the treatment was evaluated by compare the form of glottis, the scale of dyspnea and the change of voice preoperatively and postoperatively, as well as the occurrence of surgery complications such as dysphonia and dysphagia. Result:①All patients showed alleviation of dyspnea and had the endotracheal tube removed successfully in 1-2 months after the surgery. ②All patients were satisfied with their pronunciation and the objective index showed that all voice grading was between mild and moderate. ③Only two patients had suffered slightly bucking while on a liquid diet or eating too fast, but the symptoms had disappeared after some exercises and eating properly. Conclusion:Unilateral CO₂ laser partial arytenoidectomy is an effective, economic and less-suffering procedure which can not only solve the dyspnea results from bilateral vocal fold abductor paralysis but also can be grasped quickly by the surgeons.

InP-based pseudomorphic InAs/InGaAs triangular quantum well lasers with bismuth surfactant

An InP-based 2.1 μm InAs/In_0.53Ga_0.47As triangular quantum well laser grown with Bi surfactant has shown improved performance in comparison to the device with the same structure but grown without Bi surfactant. Under continuous-wave driving operation, the output light power is increased from 32.6 to 37.5 mW at the same injecting current of 850 mA at 200 K. The external differential and internal quantum efficiencies for the laser with Bi surfactant are 18.4% and 41%, respectively, which are correspondingly higher than 13.1% and 31% for the reference device. Furthermore, a decreased internal loss from 20.9 to 17.6  cm^-1 for the Bi surfactant laser is also observed. These results suggest that Bi surfactant is promising for further enhancing performances of strained quantum well laser diodes.

[Clinical study on treatment of early glottic carcinoma with different cordectomy]

OBJECTIVE

To explore the advantage of KTP laser cordectomy in the treatment of early glottic carcinoma.

METHOD

Follow-up observation on 30 patients who had KTP laser cordectomy and 18 patients who had laryneal split cordectomy was applied, then their postoperative laryngeal structure's change, the quality of voice and the quality of life (QOL) were compared and analyzed.

RESULT

The patient group treated by KTP laser grew out a piece of new cord just at the place where it was excised after half a year, and the quality of voice was obviously improved near to norm, and they had higher QOL. On the contrary, the other group had no newly grown cord, their quality of voice was better in the first half year but was worse last out. Their QOL was lower than the laser group before decannulation and the same as the laser group after the decannulation. There are 2 cases recurrented in the laser group and 1 case recurrented in the laryneal split group, the two groups all had no metastasis and death in laryneal carcinoma by 2-4 years follow up postoperation.

CONCLUSION

On the basis of effecting radical cure, the early glottic carcinoma treated with non-contact KTP laser with suspension laryngoscope can result in good recuperating in laryngeal structure, less injury and high QOL. So it makes micro-injury treatment in laryngeal carcinoma come true and better than the laryngeal split cordectomy.