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Objective:To analyze the feasibility of hippocampal-avoidance (HA) prophylactic cranial irradiation (PCI) in small cell lung cancer patients (SCLC)(limited stage) after chemotherapy and thoracic radiation.Methods:From June 2016 to March 2019, 40 eligible SCLC patients were recruited and randomly divided into the routine PCI ( n=22) and hippocampal-avoidance PCI (HA-PCI) groups ( n=18). The HA zone was contoured according to the criteria of RTOG 0933. Volumetric-modulated arc therapy (VMAT) was adopted in the HA-PCI group. After radiotherapy, Hopkins verbal learning test (HVLT) and MRI were performed. Results:The average hippocampus volume was (4.01±1.57) cm 3, the average HA volume was (20.13±4.14) cm 3, HA D 100% was (7.19±0.38) Gy and HA D max was (14.38±1.18) Gy. During HVLT, 1-month-after-PCI vs. before-PCI (trial3, trial4, learning, percent retained), 1-month-after-PCI vs. after-PCI (trial3, learning), HA-PCI cohort showed advantages over PCI in HVLT scores. The average follow-up time was (17.00±8.47) months. Two patients with brain metastases which were out of the HAZ received routine PCI. Conclusions:PCI using VMAT technology to protect hippocampus is feasible in dosimetry. The test results indicate that the protective effect of hippocampus protection on memory is worthy of further promotion in clinical practice.
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Background and purpose: The technique of dynamic contrast-enhanced MRI (DCE-MRI) is widely applied in differential diagnosis between benign and malignant tumor and therapeutic estimation of neoadjuvant chemotherapy in clinic. However, there is no standard quantitative measurement method. This study aimed to assess the variability of different region of interest (ROI) selections for tumor bed of breast cancer using DCE-MRI, and to ascertain the optimal ROI delineation. Methods: We retrospectively analyzed DCE-MRI of 30 patients diagnosed with breast cancer by pathology. The ROIs were delineated by 2 different observers using iCAD software with 4 methods, including whole tumor (Whole), the slice containing the most enhancing voxels (SliceMax), 3 slices centered in SliceMax (Partial) and the 5％ most enhancing contiguous voxels within SliceMax (5Max), to generate the volume transfer constant (Ktrans), the extracellular volume fraction (Ve) and rate constant (Kep). And the reproducibilities of the measurements were assessed using the Bland-Altman method. Results: In the analysis of ROIs delineation, the Ktrans, Ve and Kep reported by different observers were 1.26±0.54 vs 1.25±0.53, 0.75±0.23 vs 0.73±0.22 and 1.93±1.46 vs 1.95±1.51 (P＞0.05) using the method of Whole, and 1.28±0.43 vs 1.26±0.43, 0.74±0.21 vs 0.80±0.27, 1.95±1.53 vs 1.93±1.43 (P＞0.05) using the method of Partial, and 1.30±0.33 vs 1.32±0.33, 0.77±0.20 vs 0.73±0.24, 1.82±1.53 vs 1.87±1.45 (P＞0.05) using the method of SliceMax, and 1.31±0.35 vs 1.35±0.33, 0.77±0.20 vs 0.98±0.25, 1.97±1.36 vs 1.73±1.55 using the method of 5Max (P＜0.05). Using the methods of ROI delineation except 5Max, there was no significant difference between Ktrans, Ve and Kep reported by different observers. The bias vs limits of agreement were 0.002 vs-0.013 to 0.012,-0.003 vs-0.023 to 0.017, 0.006 vs-0.018 to 0.029,-0.035 vs-0.054 to 0.018 measured with Whole method, SliceMax, Partial and 5Max respectively using the Bland-Altman method. Conclusion: It may be reliable to measure functional parameters of primary tumors in breast cancer using DCE-MRI according to the methods of Whole, Partial and SliceMax.
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Objective The ovarian cancer is a common malignant tumor of gynaecology,and it is lack of early specific differential diagnosis.This study is to investigate the application of MR-DWI and ADC values in diagnosis of ovarian tumors,and to provide reference for clinical diagnosis.Methods 124 patients with ovarian tumors were selected as observation group,and 45 normal women were selected as the control group during the same period.MRI was performed before operation,the lesions from and image signal of MR-DWI was analyzed,and the value of ADC was measured.Results The ovarian tissues in the observation group had high or equal signal,with round or circular ovarian tumor,and uneven cystic wall spaces,while ovarian tissues in the control group had no clear boundary,with multiple follicles and low signal.The value of ADC in the observation group was (1.49±0.23)×10-3mm2/s,higher than that of the control group ((0.97±0.18)×10-3mm2/s).The difference had statistical significance (P＜0.05).The values of ADC were lower in benign tumors than in the malignant ovarian tumors,and the difference had statistical significance (P＜0.05).For patients in the observation group,the values of ADC were higher for patients in level Ⅲ than for patients in level Ⅱ,and it was higher for patients in level Ⅱ than for patients in level Ⅰ,and the difference had statistical significance (P＜0.05).The values of ADC was posi tively correlated to ovarian tumor type (r=0.763,P＜0.05),and negatively correlated to pathological classification of ovarian tumor (r=-0.947,P＜0.05).Conclusion MR-DWI and ADC values can be used to diagnose ovarian tumors.The values of ADC are positively correlated to ovarian tumors' classification,ie,the higher the ADC values,the higher classification the ovarian tumors.
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Objective To analyze the exposed dose of hippocampus(HC)of T3,T4nasopharyngeal carcinoma patients treated with intensity modulated radiotherapy(IMRT). Methods The bilateral HCs were delineated and were divided into head(HH),body(HB)and tail(HT)for 62 nasopharyngeal carcinoma patients treated with IMRT.The dose parameters of HC were then analyzed. Results The mean dose of left and right HC was(1 127±704)cGy,(1 173±762)cGy. The mean dose of left HH,HB and HT was(1 732±1029)cGy,(820±632)cGy,(423±366)cGy(P=0.000);while the mean dose of right HH, HB and HT was(1 985±1101)cGy,(837±531)cGy,(432±343)cGy(P=0.000).The exposed dose and the volume exposed in different dose of HH were obviously higher than those of HB and HT.The dose parameters of HH,HB and HT decreased in turn. The involvement of sphenoid sinus,ethmoid sinus and cavernous sinus correlated with high exposed dose of HC. Conclusions The exposed dose of HH,HB and HT was different in nasopharyngeal carcinoma patients treated with IMRT.The exposed dose of HH was the highest,which should be emphasized especially. The involvement of sphenoid sinus,ethmoid sinus and cavernous sinus suggest high exposed dose of HC.
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Objective To analyse the memory function and MRI changes in local-advanced nasopharyngeal carcinoma patients before-and after-radiation.Methods Clinical data,dosimetric data,digital span score and MRI of 14 cases with nasopharyngeal carcinom treated in Zhejiang Cancer Hospital from November 2015 to August 2016 were retrospectively analysed.There were 1 case at T2 stage,7 cases at T3 and 6 at T4.They received IMRT or TOMO therapy concurrent with 2 cycles Nedaplatin after 2-3 cycles PF/TP induction chemotherapy.Results The IMRT dosimetric data of 9 cases were available.For hippocampus and temporal lobe,the mean volume was (15.17 ± 2.17) and (95.07 ± 12.26) cm3,respectively,while the mean dose was (1 154.06 ±771.63) and (1 306.61 ±603.69) Gy,and the max dose (3 797.61 ± 1 450.98) and (5 394.17 ± 982.28) Gy,respectively.The equivalent uniform dose (EUD) was (2 233.28 ±872.73) Gy for hippocampus and (3 113.11 ±603.69) Gy for temporal lobe.10 patients received digit span score before-and 3 months after-radiotherapy.The mean score of forward digit span was 8.8 ± 1.8 before radiation and 8.1 ± 1.59 at 3 months after radiation(P ＞ 0.05),while thatof backward digit span decreased from 6.2 ± 1.04 before radiation to 5.3 ± 2.36 at 3 months after radiation (t =3.25,P ＜ 0.05).9 patients' MRI were available.Volume reduction of temporal lobe was observed (t =4.57,P ＜ 0.01) by voxel-based morphometry (VBM).Conclusions Radiation-induced injury to hippocampus and temporal lobe is inevitable in local-advanced nasopharyngeal carcinoma patients.There might be some connection between memory loss and temporal lobe volume atrophy after radiotherapy.Enrollment of larger sample analysis is expected.
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Objective To analyze the radiation doses to the head, body, and tail of the hippocampus in intensity-modulated radiotherapy(IMRT)for nasopharyngeal carcinoma(NPC). Methods Ten NPC patients treated with IMRT were selected,and the head, body, and tail of both hippocampi were delineated on T1-weighted images. The doses to the hippocampus were then analyzed. WAIS-CR speech test results were tested by paired sample t-test. Results The mean doses to left and right hippocampi were 1 147±976 cGy and 1 011±602 cGy, respectively. The mean doses to the head, body, and tail of the left hippocampus were 1 739± 1 317 cGy, 890± 982 cGy, and 547± 688 cGy, respectively(P=0.042);the mean doses to the head,body,and tail of the right hippocampus were 1 691±942 cGy,744±483 cGy,and 531±603 cGy,respectively(P=0.002).The dose to the hippocampus decreased from the head to the tail, and the irradiated volume also decreased as the dose varied. Conclusions The dose to hippocampus decreases from the head to the tail in NPC patients treated with IMRT,which is worthy of attention.