Proton and Carbon Ion Radiotherapy for Operable Early-Stage Lung Cancer: 3-Year Results of a Prospective Nationwide Registry

PURPOSE/OBJECTIVE(S)

The purpose of this analysis was to report subset analysis as to progression-free survival (PFS) and overall survival (OS) of particle-beam radiation therapy for operable early-stage lung cancer.

MATERIALS/METHODS

Patients of early-stage lung cancer (T1-T2aN0) who were eligible for radical surgery but did not wish to undergo surgery were treated by proton-ion (PT) or carbon-ion (CT) radiation therapy and enrolled in Japanese prospective registry. In this analysis, PFS and OS by clinical stage, tumor location, pathological confirmation and particle-ion type were evaluated.

RESULTS

A total of 274 patients were enrolled and included in efficacy and safety analyses. Most tumors were adenocarcinoma (44%), and 105 (38%) were not histologically confirmed and diagnosed clinically. 250 (91%) of 274 patients had tumors that were peripherally situated. 138 (50%) and 136 (50%) patients were treated by PT and CT, respectively. The median follow-up time for all censored patients was 42.8 months (IQR 36.7 - 49.0). No grade 3 or severe treatment-related toxicity was observed. 3-year PFS was 81% (95% CI;76-86) and OS was 93% (95% CI;89-96), respectively. As to particle-ion type, 3-year PFS were 79.0% and 81.9% in PT and CT (p = 0.19), and 3-year OS were 93.9% and 91.1% in PT and CT (P = 0.72), respectively. For PFS, pathological confirmation, clinical stage was significant factors but there were no significant differences by tumor location or particle-ion type; for OS, clinical stage was significant factor but there was no significant difference on pathological confirmation, tumor location or particle-ion type (Table1). Table 1. 3-year PFS and OS CONCLUSION: Particle therapy for operable early-stage lung cancer resulted in excellent 3-year OS and PFS on each subset.

Evaluation of the Possibility of Dose Realignment Adaptation by Shifting the Isocenter in Proton Beam Therapy for Pancreatic Cancer

PURPOSE/OBJECTIVE(S)

In pancreatic cancer, a tumor is surrounded by the gastrointestinal (GI) tract, which is subject to changes in location, shape, and contents. Due to these inter-fractional changes, proton beam therapy (PBT) for pancreatic cancer may result in unintentionally high doses to the GI tract. Daily adaptive re-planning can solve this problem, but is not yet established with PBT due to its resource intensive characteristics. This study aims to evaluate the GI tract dose using weekly computed tomography (CTw) and the possibility of dose realignment adaptation by shifting the isocenter (IC) of the PBT plan, which does not require re-planning.

MATERIALS/METHODS

We retrospectively analyzed 6 consecutive patients with unresectable pancreatic cancer treated with real-time-image gated PBT using a fiducial marker. The planning CT was scanned at the natural expiration of respiration and a PBT plan of 60 GyE in 25 fractions (baseline plan, PLANbase) was created. The CTw images were acquired the day before start of PBT and once a week during the PBT course thereafter. The PLANbase was rigidly transferred to the CTw based on the relationship between the three-dimensional coordinates of the fiducial marker and those of the IC in the PLANbase. The PLANeval was created by recalculating the PLANbase on the CTw. We evaluated the doses to the stomach, duodenum, and intestines in the PLANeval according to the following criteria: Dmax of the stomach < 60 GyE, duodenum and intestines < 55 GyE, and D1cc of the stomach < 55 GyE, duodenum and intestines < 54 GyE. In addition, we investigated the GI tract dose realignment adaptation for the PLANeval with its IC shifted 2mm, 4mm, and 6mm in each of 6 directions (right, left, ventral, dorsal, cranial, and caudal), respectively.

RESULTS

A total of 35 PLANeval were created for the CTw. In the PLANbase of the 6 patients, the average of Dmax and D1cc of the stomach, duodenum and intestines were 50.7 GyE (range, 46.7-53.6) and 50.0 GyE (45.0-53.2), 49.2 GyE (44.3-51.7) and 48.8 GyE (43.7-51.5), and 49.2 GyE (44.8-52.0) and 48.9 GyE (44.6-51.8), respectively. In the PLANeval, the average of Dmax and D1cc of the stomach, duodenum, and intestines were 53.3GyE (43.8-61.4) and 52.8 GyE (43.2-61.1), 51.0 GyE (36.1-60.0) and 50.3 GyE (35.4-59.8), and 52.5 GyE (36.6-61.0) and 51.9 (34.4-60.9) GyE, respectively. Twenty-two of the 35 PLANeval (63 %) did not meet at least one of the GI tract dose criteria. In 11 of 22 PLANeval with higher doses to the GI tract, the IC shift resulted in GI dose reductions and all dose criteria were met. The minimum amount of the IC shift required to meet the criteria was 2 mm for 8 plans and 4 mm for 3 plans. The remaining 11 PLANeval did not meet the criteria using dose realignment adaptation by shifting the isocenter.

CONCLUSION

Adaptive replanning is necessary for PBT for pancreatic cancers due to excessive GI tract doses in more than 60% of the plans. Dose realignment adaptation by shifting the IC, which does not require re-planning, may be an option in adaptive treatment strategies.

A Risk Prediction Model for Severe Radiation Induced Lymphopenia in Patients with Pancreatic Cancer Treated with Concurrent Chemoradiotherapy

PURPOSE/OBJECTIVE(S)

In pancreatic cancer, radiation induced lymphopenia (RIL) is associated with a poor prognosis. However, normal tissue complication probability (NTCP) models predicting RIL in pancreatic cancer treated with concurrent chemoradiotherapy (CCRT) have yet to be developed. This study aims to develop a least absolute shrinkage and selection operator (LASSO)-based multivariate NTCP model to predict severe RIL in patients with pancreatic cancer during CCRT and to validate the model internally.

MATERIALS/METHODS

We retrospectively reviewed patients with localized pancreatic cancer who underwent CCRT using three-dimensional conformal radiation therapy from 2013 to 2021. The exclusion criteria were patients with distant metastasis; patients who did not complete RT due to tumor progression; patients who did not have absolute lymphocyte count (ALC) data available before or during RT. An ALC of < 0.5 K/μL during CCRT was defined as severe RIL. A NTCP model of severe RIL was developed by LASSO-based multivariate analysis. We used age, sex, Karnofsky performance status, maximum tumor size, carbohydrate antigen 19-9 level before RT, ALC before RT, volume of planning target volume (PTV), and dosimetric parameters for surrounding organs (including spleen, vertebrae, liver, bilateral kidneys, gastrointestinal tracts) as variables for LASSO. In addition, internal validation was performed by the bootstrap method. The predictive performance of the model was evaluated by the area under the curve (AUC) of the receiver operating characteristic curve and scaled Brier score.

RESULTS

Of the 131 patients included in the study, the median age was 68 years (range, 42-84), and 55% were male. The median ALC before RT was 1.37 K/µL (0.52-3.50). The median PTV volume was 315.4 ml (86.3-1079.3). The median dose of radiotherapy was 50.4 Gy (16.2-50.4), with 1.8 Gy per fraction. Combination chemotherapy was S-1 in 99 cases (75.6%) and gemcitabine in 32 cases (24.4%). Induction chemotherapy before CCRT was performed in 39 patients (29.8%). Severe RIL was observed in 84 (63.6%) patients. The LASSO showed that low baseline ALC (p = 0.0002), large PTV volume (p < 0.0001), and a large kidney V5 defined as the percentage of bilateral kidneys receiving 5 Gy or more (p = 0.0338) were selected as parameters of the prediction model for severe RIL (AUC = 0.917) and scaled Brier score was 0.511. As a result of internal validation by the bootstrap method, the average AUC was 0.918 (95% confidence interval, 0.849-0.954).

CONCLUSION

Severe RIL occurred frequently during CCRT for pancreatic cancer, and a NTCP model for severe RIL developed and validated internally in this study showed good predictive performance. External validation is needed before this NTCP model can be used as a benchmark for treatment planning to reduce the risk of severe RIL and for considering future treatment approaches.

Quality of Palliative Radiation Therapy Assessed Using Quality Indicators: A Multicenter Survey

PURPOSE/OBJECTIVE(S)

Clinical practice is not always performed in accordance with guideline recommendations. Quality indicators (QIs) are valuable tools for evaluating the quality of healthcare systems. We sought to identify potential gaps between clinical practice and evidence using QIs previously developed using a modified Delphi method.

MATERIALS/METHODS

We used seven QIs (Table 1) to assess the quality of radiation therapy for bone (BoM) and brain metastases (BrM) at 29 centers; 13 (45%) were academic (12 university hospitals and 1 cancer center) and 16 (55%) were nonacademic hospitals. Compliance rate was calculated as the percentage of patients for whom recommended medical care was conducted. Random effects models were used to estimate pooled compliance rates. Mixed effects models with a Q test were used to compare compliance rates between academic and nonacademic centers.

RESULTS

The estimates of the compliance rates with 95% confidence intervals are presented in Table 1. For BoM-1, the compliance rate was higher in academic hospitals (100% [100-100%]) than in non-academic hospitals (96% [89-100%]) (P = 0.021). For BrM-3, the compliance rate was lower in academic hospitals (92% [81-99%]) than in nonacademic hospitals (100% [98-100%]) (P = 0.016).

CONCLUSION

A quality assessment based on these seven QIs is feasible. Overall, compliance rates were high; however, for BoM-3, the practice remains to be improved in some centers. Based on BoM-4 compliance rates, steroids are infrequently used concurrently with radiation therapy for malignant spinal cord compression. Extended fractionation for BoM was less frequently performed in academic than in nonacademic centers. The initiation of radiation therapy for brain metastases was more frequently delayed in academic than in nonacademic centers.

Morphological Classification of the Medial Frontal Cortex Based on Cadaver Dissections: A Guide for Interhemispheric Approach

The medial frontal cortex (MFC) is a part of the medial surface of the frontal lobe situated in the rostral portion of the corpus callosum (CC). In a surgical interhemispheric approach (IHA), the MFC covers the anterior communicating artery (Aco) complex until the final stage of dissection. To clarify the anatomical relationship between the MFC and the Aco complex, and to facilitate orientation in IHA, we analyzed the morphological features of the MFC in number, size, and pattern of gyri from the medial surface of the hemisphere in the subcallosal portion using 53 adult cadaveric hemispheres. The mean width of the MFC excluding cingulate gyrus (MFCexcg) was 20.6 ± as mm in the subcallosal portion. MFCexcg consisting of 2, 3, 4, or 5 gyri were observed in 7.5%, 56.6%, 32.1%, or 3.8% of the hemispheres, respectively. Bilateral MFCexcg consisting of >2 gyri were observed in approximately 85% of the hemispheres. Therefore, in many cases, the dissection performed at 2 cm upward from the base of the straight gyrus (SG) or 3–4 gyri of the MFC is sufficient to safely reach the upper portion of the cistern of lamina terminalis located distal to the Aco complex in IHA. The MFC is a good landmark for intraoperative orientation in IHA.

Demonstration of Human Fetal Bone Morphology with MR Imaging: A Preliminary Study

Purpose:

CT is a useful modality for the evaluation of fetal skeletal dysplasia but radiation exposure is unavoidable. The purpose of this study is to compare the usefulness of MRI and CT for evaluating the fetal skeletal shape.

Methods:

This study was approved by our Institutional Review Board. Fetal specimens (n = 14) were scanned on a 3T MRI scanner using our newly-developed sequence. It is based on T2*-weighted imaging (TR, 12 ms; TE for opposed-phase imaging, 6.1 ms, for in-phase imaging, 7.3 ms; flip angle, 40°). The specimens were also scanned on a 320 detector-row CT scanner. Four radiologists visually graded and compared the visibility of the bone shape of eight regions on MRI- and CT-scans using a 5-point grading system.

Results:

The diagnostic ability of MRI with respect to the 5th metacarpals, femur, fibula, and pelvis was superior to CT (all, P < 0.050); there was no significant difference in the evaluation results of observers with respect to the cervical and lumbar spine, and the 5th metatarsal (0.058 ≤ P ≤ 1.000). However, the diagnostic ability of MRI was significantly inferior to CT for the assessment of the bone shape of the thoracic spine (observers A and C: P = 0.002, observers B and D: P = 0.001).

Conclusion:

The MRI method we developed represents a potential alternative to CT imaging for the evaluation of the fetal bone structure.

An in vitro model of region-specific rib formation in chick axial skeleton: Intercellular interaction between somite and lateral plate cells

The axial skeleton is divided into different regions based on its morphological features. In particular, in birds and mammals, ribs are present only in the thoracic region. The axial skeleton is derived from a series of somites. In the thoracic region of the axial skeleton, descendants of somites coherently penetrate into the somatic mesoderm to form ribs. In regions other than the thoracic, descendants of somites do not penetrate the somatic lateral plate mesoderm. We performed live-cell time-lapse imaging to investigate the difference in the migration of a somite cell after contact with the somatic lateral plate mesoderm obtained from different regions of anterior-posterior axis in vitro on cytophilic narrow paths. We found that a thoracic somite cell continues to migrate after contact with the thoracic somatic lateral plate mesoderm, whereas it ceases migration after contact with the lumbar somatic lateral plate mesoderm. This suggests that cell-cell interaction works as an important guidance cue that regulates migration of somite cells. We surmise that the thoracic somatic lateral plate mesoderm exhibits region-specific competence to allow penetration of somite cells, whereas the lumbosacral somatic lateral plate mesoderm repels somite cells by contact inhibition of locomotion. The differences in the behavior of the somatic lateral plate mesoderm toward somite cells may confirm the distinction between different regions of the axial skeleton.

Long-term outcomes of an extracorporeal irradiated autograft for limb salvage operations in musculoskeletal tumours

Aims

We analyzed the long-term outcomes of patients observed over ten years after resection en bloc and reconstruction with extracorporeal irradiated autografts

Patients and Methods

This retrospective study included 27 patients who underwent resection en bloc and reimplantation of an extracorporeal irradiated autograft. The mean patient age and follow-up period were 31.7 years (9 to 59) and 16.6 years (10.3 to 24.3), respectively. The most common diagnosis was osteosarcoma (n = 10), followed by chondrosarcoma (n = 6). The femur (n = 13) was the most frequently involved site, followed by the tibia (n = 7). There were inlay grafts in five patients, intercalary grafts in 15 patients, and osteoarticular grafts in seven patients. Functional outcome was evaluated with the Musculoskeletal Tumor Society (MSTS) scoring system.

Results

There were no recurrences in the irradiated autograft and the autograft survived in 24 patients (88.9%). Major complications included nonunion (n = 9), subchondral bone collapse (n = 4), and deep infection (n = 4). Although 34 revision procedures were performed, 25 (73.5%) and four (11.8%) of these were performed less than five years and ten years after the initial surgery, respectively. The mean MSTS score at the last follow-up was 84.3% (33% to 100%).

Conclusion

Considering long-term outcomes, extracorporeal irradiated autograft is an effective method of reconstruction for malignant musculoskeletal tumours Cite this article: Bone Joint J 2019;101-B:1151–1159

Morphological Pattern and Classification of the Superficial Middle Cerebral Vein by Cadaver Dissections: An Embryological Viewpoint

In this study, we used 45 adult cadaveric cerebral hemispheres to investigate the anatomical classification of the superficial middle cerebral vein (SMCV) based on the number of stems, course, and anastomosis at the distal portion. We classified the SMCVs into five types based on embryological concept. Type A (18 cases, 40.0%) is that the frontosylvian veins (FSVs) merge with the vein of Trolard (VT) and the vein of Labbé (VL) at the distal portion of the sylvian fissure. Type B (5 cases, 11.1%) is that the temporosylvian veins (TSVs) merge with the VT and the VL at the distal portion. Type C (13 cases, 28.9%) is that no vein merge with the VT and the VL at the distal portion. The VT merges with the SMCV from the FSV and the VL merges with the SMCV from the TSV. They course along the sylvian fissure and merge at the proximal portion. In Type D (eight cases: 17.8%), the VT and the VL merge at the distal portion, and the SMCV from the FSV and the SMCV from the TSV join their confluence without merging. Type E (one case, 2.2%) show an undeveloped SMCV. Formation rate of intravenous anastomoses or bridging veins(BVs) at the distal portion between the frontosylvian trunk (FST) and the temporosylvian trunk (TST), between the FST and the temporal lobe, and between the TST and the frontal lobe was very low, because these formation may be difficult to occur during the embryological process in which the SMCV is formed from the telencephalic vein.

Lower grip strength and dynamic body balance in women with distal radial fractures

In this case-control study, we concluded that women with distal radial fractures who were surgically treated showed lower grip strength and dynamic body balancing than those of controls. These results suggest that measurements of grip strength and dynamic body balance may be useful screening tools to assess future fracture risk.

INTRODUCTION

Patients with distal radial fractures (DRFs) are at risk of future fragility fractures. However, their physical characteristics and tendencies for falls remain unclear. We aimed to compare the physical characteristics of women with and without distal radial fractures.

METHODS

We included 128 women with a DRF as their first fragility fracture (fracture group) who underwent surgical treatment. Concurrently, 128 age- and sex-matched participants without a history of fragility fractures were selected as controls (control group). The participants underwent assessments of grip strength and the body balancing ability test. Measurements were taken twice in the fracture group, at 2 weeks and 6 months postoperatively, and once in the control group. The body balancing ability test included the Functional Reach Test, Timed Up and Go test (TUG), 2-Step test (2ST), and Timed Uni-pedal Stance test. The participants also completed questionnaires about their health.

RESULTS

There were no significant differences (p > 0.05) in patient characteristics between the groups. The fracture group showed lower grip strength across all age groups. In the DRF group, prolonged TUG time was observed at 2 weeks postoperatively in all age groups and at 6 months in participants aged 55-74 years; the 2ST score was significantly lower in participants aged between 65 and 74 years.

CONCLUSIONS

Women with DRF demonstrated lower grip strength and dynamic body balancing ability. Lower grip strength and dynamic body balancing ability were identified as significant risk factors in women with DRF, suggesting that these may be useful screening tools to assess fracture risk.

Correction to: Lower grip strength and dynamic body balance in women with distal radial fractures

The article Lower grip strength and dynamic body balance in women with distal radial fractures, written by. K. Fujita, H. Kaburagi, A. Nimura, T. Miyamoto, Y. Wakabayashi, Y. Seki, H. Aoyama, H. Shimura, R. Kato, A. Okawa was originally published electronically on the publisher's internet portal.

Reappraisal of classification of distal cholangiocarcinoma based on tumour depth

Background

In the eighth edition of the AJCC cancer staging classification, the T system for distal cholangiocarcinoma (DCC) has been revised from a layer-based to a depth-based approach. The aim of this study was to propose an optimal T classification using a measured depth in resectable DCC.

Methods

Patients who underwent pancreatoduodenectomy for DCC at 32 hospitals between 2001 and 2010 were included. The distance between the level of the naive bile duct and the deepest cancer cells was measured as depth of invasion (DOI). Invasive cancer foci were measured as invasive tumour thickness (ITT). Log rank χ2 scores were used to determine the cut-off points, and concordance index (C-index) to assess the survival discrimination of each T system.

Results

Among 404 patients, DOI was measurable in 182 (45·0 per cent) and ITT was measurable in all patients, with median values of 2·3 and 5·6 mm respectively. ITT showed a positive correlation with DOI (rs = 0·854, P &lt; 0·001), and the cut-off points for prognosis were 1, 5 and 10 mm. Median survival time was shorter with increased ITT: 12·4 years for ITT below 1 mm, 5·2 years for ITT at least 1 mm but less than 5 mm, 3·0 years for ITT at least 5 mm but less than 10 mm, and 1·5 years for ITT 10 mm or more (P &lt; 0·001). This classification exhibited more favourable prognostic discrimination than the T systems of the seventh and eighth editions of the AJCC (C-index 0·646, 0·622 and 0·624 respectively).

Conclusion

ITT is an accurate approach for depth assessment in DCC. The four-tier ITT classification with cut-off points of 1, 5 and 10 mm seems to be a better T system than those in the seventh and eighth editions of the AJCC classification.