[Interstitial implantation of ¹²5I seed therapy for recurrent ovarian cancer].

OBJECTIVE: To explore the feasibility, short-term efficacies and complications of computed tomography (CT)-guided ¹²5I interstitial implant therapy for recurrent ovarian cancer. METHODS: From October 2009 to November 2010, a total of 25 lesions for 12 patients were diagnosed as recurrent ovarian cancer by positron emission tomography/computed tomography (PET/CT). Among 25 lesions, 21 underwent ¹²5I seed implantation. And 4 lesions of liver and spleen in one patient were treated with microwave ablation. Nine patients underwent 2 - 6 cycles of chemotherapy after seeding. There were 11 lesions with diameter > 2 cm and 10 ≤ 2 cm. According to the area of physiologic 18FDG uptake in lesions, the treatment plans were formulated by computerized treatment planning system (TPS) and Memorial Sloan-Ketterin nomograph. The matched peripheral dose (MPD) was 145 Gy in target mass. A median of 20.5 seeds per patient (range: 9 - 45) were implanted. The efficacies were evaluated by CT and 18F-FDG PET/CT findings. RESULTS: One patient died of renal failure while the other patients survived during a median follow-up of 15 mouths (range: 9 - 19). Ten lesions showed complete remission, 6 partial remission and 5 progressive disease. The effective rate was 76.2% (16/21). Compared with those > 2 cm, the lesions ≤ 2 cm in diameter had a better local control rate by Fisher's exact test (P = 0.035). The hepatic and renal lesions treated by microwave ablation showed inactivation on PET/CT. Only one patient suffered from sciatic nerve injury caused by punctuation and numbness and pain of right lower extremity were persistent. There was no onset of the complications of radiation injury, such as intestinal fistula and proctitis. CONCLUSION: The CT-guided ¹²5I interstitial implant therapy for recurrent ovarian cancer yields excellent short-term efficacies with fewer complications. The combined modality of ¹²5I interstitial implant and chemotherapy may further improve the patient outcomes.

Experimental study of destruction to porcine spleen in vivo by microwave ablation.

AIM: To discuss the safety, feasibility and regularity of destruction to porcine spleen in vivo with congestion and tumescence by microwave ablation (MWA). METHODS: Ligation of the splenic vein was used to induce congestion and tumescence in vivo in five porcine spleens, and microwave ablation was performed 2-4 h later. A total of 56 ablation points were ablated and the ablation powers were 30-100 W. The ablation time (1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 min) was performed at a power of 60 W. After ablation, the ablation size was measured in pigs A, C, D and E and spleen resection. In pig B, the ablation size was measured and 2 ablation points were sent for pathology analysis and all tissues were sutured following ablation. Pig B was killed 1 wk later and the ablation points were sent for pathology analysis. Bleeding, tissue carbonization surrounding electrodes, and pathological changes were observed, and the effect on destruction volume relative to different ablation powers, times and positions was analyzed. RESULTS: The incidence of bleeding (only small am-ounts, < 20 mL) in the course of ablation was 5.4% (3/56) and was attributed to tissue carbonization surrounding electrodes, which also exhibited an incidence of 5.4% (3/56). The destruction volume was influenced by different ablation powers, times and points. It showed that the ablation lesion size increased with increased ablation time, from 1 to 10 min, when the ablation power was 60 W. Also, the ablation lesion size increased with the increase of ablation power, ranging from 30 to 100 W when the ablation time was set to 3 min. A direct correlation was seen between the destruction volume and ablation time by the power of 60 W (r = 0.97542, P < 0.0001, and also between the destruction volume and ablation powers at an ablation time of 3 min (r = 0.98258, P < 0.0001). The destruction volume of zone II (the extra-2/3 part of the spleen, relative to the first or second class vascular branches), which was near the hilum of the spleen, was noteably larger than the destruction volume of zoneI(the intra-1/3 part of the spleen) which was distal from the hilum of the spleen (P = 0.0015). Pathological changes of ablation occurring immediately and 1 wk after MWA showed large areas of coagulation. Immediately following ablation, intact spleen tissues were observed in the areas of coagulation necrosis, mainly around arterioles, and there were no obvious signs of hydropsia and inflammation, while 1 wk following the ablation, the coagulation necrosis was well distributed and complete, as many nuclear fragmentations were detected, and there were obvious signs of hydropsia and inflammation. CONCLUSION: In vivo treatment of congestion and tumescence in the spleen using microwave ablation of water-cooled antenna is a safe and feasible method that is minimally invasive.

Radioablation settings affecting the size of lesions created ex vivo in porcine livers with monopolar perfusion electrodes.

RATIONALE AND OBJECTIVES: To explore the morphological characteristics of ablated lesions and find which combination of duration, temperature, and power was preferable to create largest lesion size with monopolar perfusion electrodes. MATERIALS AND METHODS: Using monopolar perfusion electrodes to create 72 lesions in 30 excised porcine livers with radiofrequency radiation at different durations (5, 10, 15, and 20 minutes), temperatures (83 degrees C, 93 degrees C, 103 degrees C, and 113 degrees C), and powers (20, 30, and 40 W). Lesion volumes were calculated from longitudinal diameters and transverse diameters. Morphological characteristics were assessed microscopically from slides stained with hematoxylin and eosin. RESULTS: Positive correlations were found between duration and longitudinal diameter (r = 0.66; P < .001), transverse diameter (r = 0.66; P < .001), distance of ablation beyond the electrode tip (r = 0.56; P < .001), and volume of lesions (r = 0.66; P < .001). Temperature was also positively correlated with longitudinal diameter (r = 0.70; P < .001), transverse diameter (r = 0.72; P < .001), distance of ablation beyond the electrode tip (r = 0.61; P < .001), and lesion volume (r = 0.711; P < .001). Lesion size did not increase when duration was longer than 15 minutes and temperature was higher than 103 degrees C. Power was not correlated with lesion size. Lesion size did not increase with increasing power. Macroscopically, all lesions were elliptical in cross section and appeared three zones: a central zone (I), a coagulated necrotic zone (II), and a hemorrhagic and edematous zone (III) from inside to outside. Microscopically, cells morphology and the nucleus were irregular or even disappeared in zone I. In zone II and III, cells did not appear deformation. CONCLUSION: Duration and temperature, not power, affected lesion size. The largest lesion size was about 3.5 cm x 2.5 cm x 2.5 cm as temperature and duration was 15 minutes/103 degrees C.