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Objective:To compare the efficacy and safety of standard treatment with or without adjuvant chemotherapy in patients with highly malignant non-metastatic prostate cancer.Methods:In this prospective non-randomized controlled study, consecutive non-metastatic prostate cancer patients with pathologically proven Gleason score of 9-10 or Gleason score of 5 admitted to Peking University First Hospital were enrolled. Four to six cycles of chemotherapy using docetaxel ± carboplatin regimen were added or not after standard radical therapy. The primary end point was 5-year event-free survival (EFS), and the secondary end points were distant metastasis-free survival (MFS), overall survival (OS), and treatment-related adverse events. The survival curve was drawn by Kaplan-Meier method. The differences between two groups were analyzed by log-rank test.Results:A total of 176 patients were consecutively enrolled from November 2019 to January 2022 of which 138 patients received only standard radical therapy (control group), and 38 patients received adjuvant chemotherapy after standard radical therapy (chemotherapy group). The median follow-up time was 13.4 (2.0-34.0) months. All patients survived. The 30-month EFS rates in the chemotherapy and control groups were 100% and 85.6%, respectively ( P=0.064). There were no events in the chemotherapy group, while there were 12 cases of events in the control group, including 6 cases of biochemical recurrence and 6 cases of imaging progression. The 30-month MFS rates in two groups were 100% and 91.9%, respectively ( P=0.205). After the 1 vs. 2 propensity score matching, the EFS and MFS rates in two groups were 100% vs. 85.7% ( P=0.056), and 100% vs. 92.2% ( P=0.209), respectively. The incidence rates of grade 2 and above urinary toxicity in the chemotherapy and control groups were 2.6% and 7.2% ( P=0.354), respectively. The incidence rates of grade 2 and above rectal toxicity were 5.3% and 5.1% ( P=0.711), respectively. Grade 3 and above chemotherapy-related toxicity in the chemotherapy group were leukopenia (31.6%), thrombocytopenia (2.6%) and alopecia (13.2%). Conclusion:The addition of adjuvant chemotherapy after standard radical therapy tends to improve the overall EFS of patients with highly malignant prostate cancer, and the adverse effects are tolerable, which should be confirmed by long-term follow-up results.
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Objective:To investigate the advantage of three dimensional(3D)-printed tissue compensators in radiotherapy for superficial tumors at irregular sites.Methods:A subcutaneous xenograft model of prostate cancer in nude mice was established. Mice were randomly divided into no tissue compensator group( n=6), common tissue compensator group( n=6), and 3D-printed tissue compensator group( n=6). Computed tomography (CT) images of nude mice in the 3D-printed tissue compensator group were acquired. Compensator models were made using polylactic acid, and material properties were evaluated by measuring electron density. CT positioning images of the three groups after covering the corresponding tissue compensators were acquired to delineate the gross tumor volume (GTV). Nude mice in the three groups were irradiated with 6 MV X-rays at the prescribed dose. The prescribed dose for the three groups was 1 500 cGy. The dose distribution in the GTV of the three groups was calculated and compared using the analytical anisotropic algorithm in the Eclipse 13.5 treatment planning system. The metal-oxide-semiconductor field-effect transistor was used to verify the actual dose received on the skin surface of nude mice. Results:The air gap in the 3D-printed tissue compensator group and the common tissue compensator group was 0.20±0.07 and 0.37±0.07 cm 3, respectively ( t=4.02, P<0.01). For the no tissue compensator group, common tissue compensator group, and 3D-printed tissue compensator group, the D95% in the target volume was (1 188.58±92.21), (1 369.90±146.23), and (1 440.29±45.78) cGy, respectively ( F=9.49, P<0.01). D98% was (1 080.13±88.30), (1 302.76±158.43), and (1 360.23±48.71) cGy, respectively ( F=11.17, P<0.01). Dmean was (1 549.08±44.22), (1 593.05±65.40), and (1 638.87±40.83) cGy, respectively ( F=4.59, P<0.05). The measured superficial dose was (626.03±26.75), (1 259.83±71.94), and (1 435.30±67.22) cGy, respectively ( F=263.20, P<0.001). The percentage variation in tumor volume growth after radiation was not significantly different between the common tissue compensator group and the 3D-printed tissue compensator group ( P>0.05). Conclusions:3D-printed tissue compensators fit well to the body surface, which reduces air gaps, effectively increases the dose on the body surface near the target volume, and provides ideas for radiotherapy for superficial tumors at some irregular sites.
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Objective:Partial stereotactic ablative boost radiotherapy(P-SABR)is a method to deliver SABR boost to the gross tumor boost volume(GTVb), followed by conventionally fractionated radiotherapy to the whole tumor area(GTV). GTVb is the max volume receiving SABR while ensuring the critical organ-at-risk(OAR)falloff to 3 GyE/f. We investigated the potential advantage of proton therapy in treating bulky non-small cell lung cancer(the tumor length greater than 8 cm).Methods:Nine patients with bulky NSCLC treated with photon P-SABR in our institute were selected. For the treatment planning of proton therapy, the GTVb target area was gradually outwardly expanded based on the photon GTVb target area until the dose to critical OARs reached 3 GyE/f. The GTV and CTV areas remained the same as photon plan. A proton intensity-modulated radiation treatment plan(proton-IMPT), a photon intensity-modulated radiation treatment plan(photon-IMRT)and a photon volumetric modulated arc therapy(photon-VMAT)were created for each patient, respectively. The dosimetric parameters of different treatment plans were compared.Results:The volume ratio of GTVb-photon and GTVb-proton to GTV was(25.4±13.4)% and(69.7±30.0)%,respectively( P<0.001). In photon-IMRT, photon-VMAT, and proton-IMPT plan groups, the mean dose of CTV was(76.1±4.9)Gy, (78.2±3.6)Gy, and(84.7±4.9)Gy, respectively; the ratio of tumor volume with Biologic Effective Dose(BED)≥ 90 Gy to GTV volume was(70.7±21.7)%, (76.8±22.1)%,and(97.9±4.0)%,respectively. The actual dose and BED to the tumor area of the proton-IMPT plan group were significantly higher than those of the photon plan group(both P<0.05). Besides, the OARs dose was significantly decreased in the proton-IMPT group, with(49.2±22.0)%, (56.8±19.0)% and(16.1±6.3)% of the whole lung V5 for photon-IMRT, photon-VMAT and proton-IMPT, respectively(all P<0.001). Conclusions:Larger GTV boost target volume, higher BED and reduced OARs dose can be achieved in proton plans compared with photon plans. Proton P-SABR is expected to further improve the local control rate of bulky NSCLC with fewer adverse effects.
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Objective:To investigate the efficacy and safety of radiotherapy for all metastases in patients with metachronous oligo-metastatic prostate cancer after radical treatment.Methods:From October 2011 to February 2021, 41 patients with prostate cancer with less than 5 metastases after radical treatment were retrospectively analyzed in a single center. The median age at radiotherapy was 68 (57-81) years. Forty patients (98%) received androgen deprivation therapy (ADT). There were 28 patients in the hormone sensitive (HSPC) group and 13 patients in the hormone resistant (CRPC) group. The median initial PSA was 24.4 (7.4-399.0) ng/ml. Tumor stage: T 2 stage 11 patients, T 3 stage 27 patients, T 4 stage 3 patients.30 patients were in N 0 stage and 11 patients in N 1 stage. Gleason score was 7 in 12 patients, 8 in 9 patients, 9 in 18 patients, and 10 in 2 patients.33 patients were treated with surgery, and 8 patients were treated with radiotherapy. The time span from diagnosis to metastasis was 3.1 (0.2-1.8) years. Conventional imaging examination (CT/ MRI/bone scan) before radiotherapy was used in 7 patients, and PSMA PET/CT examination was used in 34 patients.The median PSA before radiotherapy was 1.3(0.1-33.8) ng/ml. There were 62 metastases in 41 patients, including 1 lesion in 28 patients, 2 lesions in 9 patients, 3 lesions in 2 patients, and 5 lesions in 2 patients. Fifty-four patients had bone metastases and eight had retroperitoneal lymph node metastases. Twenty-two bone metastases were located in the pelvis, 18 in the vertebral body, 12 in the ribs, one in the femur and one in the sternum.The median metastatic volume was 5.8(0.2-81.7) cm 3.Daily image-guided rotational intensity modulated radiotherapy was used to cover all metastases.Dose segmentation modes include 37.5Gy/7.5Gy/5F, 60Gy/3Gy/20F, 65-70Gy/2.6-2.8Gy/25F.The median biological effective dose (BED 3) was 120 (67-147) Gy. The primary endpoint was biochemical progression-free survival (BPFS), the secondary endpoints were acute and late toxic side effects, local relapse-free survival (LPFS), and overall survival (OS). Results:The median follow-up time was 21 months (range 5-72 months). All patients completed radiotherapy, and 16 patients had grade 1 to 2 acute toxicity and side effects, and no grade 3 or above acute and late stage side effects. 1-year LPFS was 97.1%.The 1-year and 2-year BPFS were 77.5% and 59.2%, respectively. The median BPFS time was 29 months (range 13.9-44.2 months). Univariate analysis showed that the HSPC group ( P<0.001) and the group with total metastatic volume ≤ 5.8cm 3 ( P=0.010) had higher BPFS. The median BPFS time was 37 months in the retroperitoneal lymph node metastases subgroup and 17 months in the bone metastases subgroup ( P=0.141). In the HSPC group, the median BPFS was 30(22-38) months. After radiotherapy, PSA decreased in all 28 patients, and increased in 6 patients. The median BPFS was 12(4-18) months. In the CRPC group, the median BPFS was 4(0-8) months. PSA decreased in 10 patients (76.9%) after radiotherapy, and PSA decreased in 6 patients. The median BPFS was 5(3-28) months. Three patients’PSA did not decrease after radiotherapy, and they were treated with new endocrine therapy drugs, chemotherapy, immunotherapy and other systemic therapy. Conclusions:For patients with metachronous metastases after radical treatment, full coverage radiotherapy has good safety and high local control rate. HSPC patients and patients with low tumor load could be recommended to receive radiotherapy for all metastatic lesions preferentially, and patients with only retroperitoneal lymph node metastases may have better prognosis after radiotherapy than patients with bone metastases.
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Objective:To evaluate the dosimetric properties of intensity-modulated proton therapy (IMPT) plans for simulated treatment planning in patients with ventricular tachycardia (VT) using stereotactic ablative body radiotherapy (SABR), in comparison with the volumetric-modulated arc therapy (VMAT).Methods:A total of 25 gross target volume (GTV) of the apical, anterior, septal, inferior and lateral wall of the left ventricle (LV) were delineated on the CT simulation images of 5 patients with complete data. An additional 5 mm GTV margin was added to the internal target volume (ITV), and an additional 3 mm ITV margin was added to the planning target volume (PTV). VMAT and IMPT plans were designed in each target area. Dose prescription was 25 Gy (RBE) in a single fraction. The dosimetric differences of ITV and organ at risk (OAR) were compared between VMAT and IMPT.Results:The median volume of ITV was 45.40 cm 3(26.72-67.59 cm 3). All plans had adequate target coverage(V 95%Rx≥99%). Compared with the VMAT plans, IMPT reduced the D mean of whole heart, pericardium and non-target cardiac tissues (relative difference) by 44.52%, 44.91% and 60.16%, respectively, which also reduced D 0.03 cm 3 of the left anterior descending artery by 17.58%( P<0.05). After stratified analysis according to the lesion sites, IMPT could still reduce the dose of most OAR. However, the D 0.03 cm 3 of LAD and LCX for the lesions in the anterior wall of LV, the D 0.03 cm 3 of LCX in the inferior wall and D 0.03 cm 3 of LAD in the apical wall did not significantly differ (both P>0.05). Conclusions:Both VMAT and IMPT plans can meet the clinical dosimetric requirements when SABR is simulated in patients with VT. However, IMPT can lower the dose of normal heart tissues, which has the potential benefit of reducing the risk of complications, such as ischemic heart disease, pericarditis/pericardial effusion, etc.
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Objective To compare the toxicity between different dose fractionation regimens in postoperative radiotherapy for prostate cancer. Methods Patients with prostate cancer who received postoperative radiotherapy with moderate hypo-fractionation ( 62. 75 Gy in 25 fractions, 2. 51 Gy per fraction) or conventional fractionation (72 Gy in 36 fractions, 2 Gy per fractions) in our hospital from 2011 to 2017 were enrolled as subjects.All patients received intensity-modulated radiotherapy and daily cone-beam computed tomography image-guided radiotherapy. According to the propensity score matching ( PSM ) method, 35 patients treated with moderately hypo-fractionated radiotherapy were matched to 35 patients treated with conventionally fractionated radiotherapy based on age, irradiated volume, hormonal therapy, interval between surgery and radiotherapy, and comorbidities ( diabetes and hypertension). Toxicity was evaluated according to Radiation Therapy Oncology Group criteria. Comparison was made by the Fisher's exact probability test. Results One hundred and thirteen patients, consisting of forty-one in moderate hypo-fractionation group and seventy-two in conventional fractionation group, were enrolled as subjects. The median follow-up time in the two groups was 5. 6 and 45. 0 months, respectively. There were no significant differences in incidence rates of grade 2 acute gastrointestinal (GI) or genitourinary (GU) toxicity between the two groups ( 7% vs. 7%, P＝ 1. 000; 15% vs. 17%, P＝ 0. 847). After PSM, there were still no significant differences in incidence rates of grade 2 acute GI or GU toxicity between the two groups (9% vs. 11%, P＝0. 814; 14% vs. 11%, P＝ 0. 670). None of patients reported ≥grade 3 GI or GU toxicity. Conclusions Preliminary results show that moderate hypo-fractionation, compared with conventional fractionation, does not increase the risk of acute GI or GU toxicity in patients undergoing postoperative radiotherapy for prostate cancer.
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Objective To assess the acute toxicity of a hypo-fractionated regimen of intensity-modulated radiotherapy to the prostatic bed after prostatectomy.Methods From February to August 2017,twenty cases with prostate adenocarcinoma after prostatectomy were recruited.The prescribed dose to the whole pelvis and the prostatic bed was 45 Gy delivered in 1.8 Gy per fraction and 62.75 Gy delivered in 2.51 Gy per fraction,respectively.Acute toxicity was recorded and graded according to Radiation Therapy Oncology Group (RTOG) criteria and Common Terminology Criteria for Adverse Events (CTCAE) 4.0.Results The median follow-up was 7.5 months.Grade 2 acute genitourinary and gastrointestinal toxicity was observed respectively in two cases (10％) and one (5％),respectively.Two cases (10％) complained of grade 2 urinary incontinence during radiation therapy,but recovered to grade 0 or grade 1 after the first month of follow-up.Conclusions After prostatectomy,moderately hypo-fractionated radiotherapy (2.51 Gy × 25) compared with conventional fractionated radiotherapy previously reported did not increase the risk of acute toxicity.The incidence of urinary incontinence did not increase during short-term of follow-up.