Optical Surface-guided Radiation Therapy for Upper and Lower Limb Sarcomas: An Analysis of Setup Errors and Clinical Target Volume-To-Planning Target Volume Margins.

Purpose: To assess the clinical benefits of surface-guided radiation therapy (SGRT) in terms of setup error, positioning time, and clinical target volume-to-planning target volume (CTV-PTV) margin in extremity soft tissue sarcoma (STS). Methods and Materials: Fifty consecutive patients treated with radiation therapy were selected retrospectively. Treatment setup was performed with either laser-based imaging only (control group), or with laser-based and daily optical surface-based imaging (SGRT group). Pretreatment cone beam computed tomography images were acquired daily for the first 3 to 5 fractions and weekly thereafter, with the frequency adjusted as necessary. Translational and rotational errors were collected. CTV-PTV margin was calculated using the formula, 2.5Σ + 0.7σ. Results: Each group consisted of 10 and 15 upper and lower limb STSs, respectively. For patients with upper limb sarcomas, the translation errors were 1.64 ± 1.34 mm, 1.10 ± 1.50 mm, and 1.24 ± 1.45 mm in the SGRT group, and 1.48 ± 3.16 mm, 2.84 ± 2.85 mm, and 3.14 ± 3.29 mm in control group in the left-right, supero-inferior, and antero-posterior directions, respectively. Correspondingly, for patients with lower limb sarcomas, the translation errors were 1.21 ± 1.65 mm, 1.39 ± 1.71 mm, and 1.48 ± 2.10 mm in the SGRT group, and 1.81 ± 2.60 mm, 2.93 ± 3.28 mm, and 3.53 ± 3.75 mm in control group, respectively. The calculated CTV-PTV margins of the SGRT group and control group were 5.0, 3.8, 4.1 versus 5.9, 9.1, 10.1 mm for upper limb sarcomas; and 4.2, 4.7, 5.2 mm versus 6.3, 9.6, and 11.4 mm for lower limb sarcomas in the left-right, supero-inferior, and antero-posterior directions, respectively. Conclusions: Daily optical surface guidance can effectively improve the setup accuracy of extremity STS patients, and safely reduce the required CTV-PTV margins.

Application of four-dimensional cone beam computed tomography in lung cancer radiotherapy.

OBJECTIVE: This study explored the application of four-dimensional cone beam computed tomography (4D CBCT) in lung cancer patients, seeking to improve the accuracy of radiotherapy and to establish a uniform protocol for the application of 4D CBCT in radiotherapy for lung cancer. METHODS: 4D CBCT was applied to evaluate tumor volume response (TVR), motion, and center coordinates during radiotherapy in 67 eligible individuals with lung cancer diagnoses. The differences between 4D CBCT and 3D CBCT in different registration methods were compared. RESULTS: TVR was observed during treatment in 41% of patients (28/67), with a mean volume reduction of 41.7% and a median time to TVR of 19 days. Tumor motion was obvious in 16 patients, with a mean value of 0.52 cm (0.22 to 1.34 cm), and in 3 of 6 tumors close to the diaphragm (0.28 to 0.66 cm). Gray value registration based on mean density projection could still achieve close results to the 4D gray value registration. However, when the registration was based on bone alone, partial off-targeting occurred in the treatment in 41.8% of cases. The off-target rate was 19.0% when the tumor motion was ≤ 0.5 cm and 52.2% when the motion was > 0.5 cm. CONCLUSION: Tumor volume and motion of intrapulmonary lesions in individuals diagnosed with lung cancer varied significantly in the third week of radiotherapy. 4D CBCT may be more advantageous for isolated lesions without reference to relative anatomical structures or those near the diaphragm. Grayscale registration based on mean density projection is feasible.

Corrigendum: Superiority of integrated cervicothoracic immobilization in the setup of lung cancer patients treated with supraclavicular station irradiation.

[This corrects the article DOI: 10.3389/fonc.2023.1135879.].

Superiority of integrated cervicothoracic immobilization in the setup of lung cancer patients treated with supraclavicular station irradiation.

Objective: To investigate the superiority of the integrated cervicothoracic immobilization devices (ICTID) on the mobility of the supraclavicular station in lung cancer patients requiring both primary lung lesion and positive supraclavicular lymph nodes irradiation. Methods: One hundred patients with lung cancer were prospectively enrolled in the study. The following four different fixation methods are used for CT simulation positioning: thoracoabdominal flat immobilization device fixation with arms lifting (TAFID group), head-neck-shoulder immobilization device fixation with arms on the body sides (HNSID group), ICTID fixation with arms on the body sides (ICTID arms-down group), and n ICTID fixation with arms lifting (ICTID arms-up group). Cone-beam computed tomography (CBCT) images are taken daily or weekly before treatment, to assess anatomical changes during the radiotherapy course. Results: The translation errors in X (left-right direction), Y (head-foot direction), and Z (abdomen-back direction) directions of the ICTID arms-up, TAFID, ICTID arms-down and HNSID groups were (0.15 ± 0.18) cm, (0.15 ± 0.16) cm, (0.16 ± 0.16) cm, and (0.15 ± 0.20) cm; (0.15 ± 0.15) cm, (0.21 ± 0.25) cm, (0.28 ± 0.23) cm, and (0.27 ± 0.21) cm; (0.13 ± 0.14) cm, (0.15 ± 0.14) cm, (0.17 ± 0.13) cm, and (0.16 ± 0.14) cm, respectively. Among them, the ICTID arms-up group had the minimal setup errors in X direction than those in ICTID arms-down (p=0.001) and HNSID groups (p=0.001), and in Y direction than those in TAFID (p<0.001), and in Z direction than those in ICTID arms-down (p<0.001) and TAFID groups (p=0.034). For the rotational errors of the four groups in the directions of sagittal plane, transverse plane, and coronal plane, the ICTID arms-up group had the smallest setup errors in the sagittal plane than that of TAFID groups and similar rotation setup errors with those of the other three groups. Conclusion: For patients requiring radiation of primary lung lesion and positive supraclavicular lymph nodes, an integrated frame fixation device is preferred the ICTID arms-up methods provide the smallest set up error and satisfied repeatability of body position, compared with TAFID and HNSID.

Comparison of setup errors of immobilization devices for thoracic radiotherapy.

Performance of thoracic radiotherapy may be assisted by the use of thoracoabdominal flat immobilization devices (TAFIDs) and integrated cervicothoracic immobilization devices (ICTIDs). This study was performed to compare setup errors of TAFIDs and ICTIDs. Forty-four patients with lung cancer were retrospectively reviewed; 22 patients were immobilized with a TAFID and 22 with an ICTID. In total, 343 cone-beam computed tomography images of these patients were collected for radiotherapy setup. The 3-dimensional setup errors and the displacement of the acromioclavicular joint against the supraclavicular region were calculated. An independent-samples t-test and rank-sum test were used for statistical analyses. The translational setup errors of the TAFID group vs ICTID group in the left-right (LR), superior-inferior (SI), and anterior-posterior (AP) directions were 0.14 ± 0.17 vs 0.14 ± 0.16 cm (p = 0.364), 0.23 ± 0.26 vs 0.15 ± 0.15 cm (p = 0.000), and 0.16 ± 0.15 vs 0.12 ± 0.14 cm (p = 0.049), respectively. The relative displacement of the acromioclavicular joint against the supraclavicular joint in the LR, SI, and AP directions were 0.10 ± 0.12 vs 0.09 ± 0.10 cm (p = 0.176), 0.13 ± 0.13 vs 0.11 ± 0.12 cm (p = 0.083), and 0.17 ± 0.16 vs 0.12 ± 0.11 cm (p = 0.001), respectively. The overall displacement of the supraclavicular region was 0.28 ± 0.19 vs 0.23 ± 0.15 cm (p < 0.001). The recommended planning target volume margins in the LR, SI, and AP directions were 0.46 vs 0.74 cm, 0.51 vs 0.47 cm, and 0.49 vs 0.41 cm, respectively. For patients with lung cancer, using an ICTID can reduce setup errors in the SI direction and displacements of the acromioclavicular joint and supraclavicular region compared with a TAFID. Therefore, an ICTID is preferred for patients with lung cancer with supraclavicular target volume.

Fractionated stereotactic radiotherapy for 136 patients with locally residual nasopharyngeal carcinoma.

BACKGROUND: To evaluate the efficacy and toxicity of fractionated stereotactic radiotherapy (FSRT) in patients with residual nasopharyngeal carcinoma (NPC). METHODS: From January 2000 to December 2009, 136 NPC patients with residual lesions after primary radiotherapy (RT) were treated by FSRT. The total dose of primary RT was 68.0-78.0 Gy (median, 70.0 Gy). The median time from the primary RT to FSRT was 24.5 days. Tumor volumes for FSRT ranged from 0.60 to 77.13 cm3 (median, 13.45 cm3). The total FSRT doses were 8.0-32.0Gy (median, 19.5 Gy) with 2.0-10.0 Gy per fraction. RESULTS: Five-year local failure-free survival (LFFS), freedom from distant metastasis (FFDM), overall survival (OS), and disease free survival (DFS) rates for all patients were 92.5%, 77.0%, 76.2%, and 73.6%, respectively. No statistical significant differences were found in LFFS, DFS and OS in patients with stage I/II versus stage III/ IV diseases. Nineteen patients exhibited late toxicity. T stage at diagnosis was a significant prognostic factor for OS and DFS. Age was a prognostic factor for OS. CONCLUSION: FSRT after external beam radiotherapy provides excellent local control for patients with residual NPC. The incidence of severe late toxicity is low and acceptable. Further investigation of optimal fractionation regimens will facilitate reduction of long-term complications.

Fractionated stereotactic radiotherapy with vagina carotica protection technique for local residual nasopharyngeal carcinoma after primary radiotherapy.

BACKGROUND: Local failure of nasopharyngeal carcinoma (NPC) after radiotherapy (RT) remains one of the major treatment failures. This study aimed to evaluate the clinical efficacy and complications of fractionated stereotactic radiotherapy (FSRT) with vagina carotica protection technique for local residual of NPC patients after the primary RT. METHODS: From August 2006 to August 2010, FSRT with vagina carotica protection technique was applied to 36 patients in our department, the patients aged between 13 and 76 years with a median of 41.3 years, 25 of them were male and 11 were female. According to 2002 Union for International Cancer Control (UICC) Staging System, the stages before primary radiotherapy were: IIa 2, IIb 5, III 18, IVa 7, IVb 4. In the first course of radiotherapy, 9 patients received conventional RT, 27 patients received intensity modulated radiotherapy (IMRT) and 20 out of the 36 patients received concurrent chemoradiotherapy. The total dose in the first course of RT was 69.96 - 76.90 Gy (median, 72.58 Gy). The intervals between the primary RT and FSRT ranged from 12 to 147 days (median, 39.8 days). Target volumes ranged from 1.46 to 32.98 cm(3) (median, 14.94 cm(3)). The total FSRT doses were 10.0 - 24.0 Gy (median, 16.5 Gy) with 2.0 - 5.0 Gy per fraction. The most common regimen was 15 Gy in 5 fractions of 3 Gy, the irradiation dose to vagina carotica was less than 2 Gy per fraction. RESULTS: The median follow-up time was 34 months (range, 12 - 59 months). The 3-year local control rate was 100%; the 3-year overall survival rate was 94.4%; the 3-year disease-free survival rate was 77.8%. In this study, we had one case of cranial nerve injury, two cases of temporal lobe necrosis, and no nasopharyngeal massive hemorrhage was observed. CONCLUSION: FSRT with vagina carotica protection technique is an effective and safe RT regimen for local residual of NPC with reduction of radiation-related neurovascular lesions.