Heart and Coronary Artery Dose Sparing in Left-sided Breast Cancer: 3D-Conformal Radiotherapy vs. Helical Tomotherapy

BACKGROUND/AIM

To compare heart, left ventricle (LV) and coronary artery dose-sparing with three-dimensional conformal radiotherapy (3D-CRT) vs. helical tomotherapy (HT) in left-sided breast cancer (BC).

PATIENTS AND METHODS

3D-CRT and HT treatments were planned for 20 patients (pts). Computed tomography (CT) scans without and with intravenous contrast (ic) were performed and co-registered. Left breast and organs at risk (OARs) were contoured. Dose-volume histograms (DVHs) for 3D-CRT and HT treatment plans were evaluated in terms of planning target volume for evaluation (PTVeval) coverage and dose to the OARs.

RESULTS

HT provided the best target coverage and significantly reduced D2% and mean dose to the left anterior descending artery (LADA) and to the LADA-planning organ at risk volume (PRV), D2%, V5 and mean dose to the LV and D2% and V25 to the heart. As expected, due to the rotational delivery, the dose to all other coronary arteries and their PRV, contralateral breast and lungs was higher with HT.

CONCLUSION

In left-sided BC, HT provided the best target coverage and significantly reduced LV and LADA doses. Moreover D2% and V25 to the heart were significantly reduced. Further studies are needed to correlate dosimetric findings with in-depth cardiac monitoring.

Salvage radiotherapy in patients affected by oligorecurrent pelvic nodal prostate cancer

PURPOSE

Metastasis-directed therapy (MDT) is an investigational treatment option in patients with oligorecurrent prostate cancer (PCa). The aim of this retrospective study is to report oncologic outcome and toxicity of elective nodal radiotherapy (ENRT) in PCa patients affected by pelvic nodal oligorecurrence.

METHODS

41 consecutive patients were treated with salvage radiotherapy. At biochemical recurrence after primary treatment, oligorecurrent disease was detected by positron emission tomography (PET) in 94% of the patients. Image-guided intensity modulated radiation therapy (IMRT) was delivered using tomotherapy. 83% of the patients received androgen deprivation therapy (ADT) in combination with ENRT. Survival analysis was performed with Kaplan-Meier method, log-rank test was used to analyze associations between survival end-points and clinical parameters. Multivariate analysis was performed using Cox proportional hazards regression models. Toxicity was registered according to Common Terminology Criteria for Adverse Events (CTCAE) v4.0.

RESULTS

The median at follow-up was 33.6 months. At 3 years, overall survival (OS), cancer-specific survival (CSS), and biochemical progression-free survival (b-PFS) were 89%, 92%, and 53%, respectively. At univariate analysis, all survival end-points were correlated with the number of positive pelvic lymph nodes at oligorecurrence (≤ 3 vs > 3). Biochemical-PFS was correlated with PSA (p = 0.034) and PSA doubling time (p = 0.004) at oligorecurrence. At multivariate analysis, no independent variable was statistically significant. No patient experienced grade ≥ 2 late toxicity after radiotherapy.

CONCLUSIONS

The number of metastatic lymph nodes and PSA doubling time seems to be important prognostic factors in the pelvic oligorecurrent setting. Salvage radiotherapy combined with short-course ADT might be a valid treatment strategy.

Impact of Gastrointestinal Side Effects on Patients' Reported Quality of Life Trajectories after Radiotherapy for Prostate Cancer: Data from the Prospective, Observational Pros-IT CNR Study

Radiotherapy (RT) represents an important therapeutic option for the treatment of localized prostate cancer. The aim of the current study is to examine trajectories in patients' reported quality of life (QoL) aspects related to bowel function and bother, considering data from the PROState cancer monitoring in ITaly from the National Research Council (Pros-IT CNR) study, analyzed with growth mixture models. Data for patients who underwent RT, either associated or not associated with androgen deprivation therapy, were considered. QoL outcomes were assessed over a 2-year period from the diagnosis, using the Italian version of the University of California Los Angeles-Prostate Cancer Index (Italian-UCLA-PCI). Three trajectories were identified for the bowel function; having three or more comorbidities and the use of 3D-CRT technique for RT were associated with the worst trajectory (OR = 3.80, 95% CI 2.04-7.08; OR = 2.17, 95% CI 1.22-3.87, respectively). Two trajectories were identified for the bowel bother scores; diabetes and the non-Image guided RT method were associated with being in the worst bowel bother trajectory group (OR = 1.69, 95% CI 1.06-2.67; OR = 2.57, 95% CI 1.70-3.86, respectively). The findings from this study suggest that the absence of comorbidities and the use of intensity modulated RT techniques with image guidance are related with a better tolerance to RT in terms of bowel side effects.

FDG PET and Split-Bolus Multi-Detector Row CT Fusion Imaging in Oncologic Patients: Preliminary Results

PURPOSE

To assess the incremental value of split-bolus multidetector computed tomography (CT) combined with fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) for follow-up of oncologic patients.

MATERIALS AND METHODS

The institutional ethics committee approved the use of this protocol. Thirty-eight oncologic patients who underwent FDG PET/unenhanced multidetector CT and split-bolus multidetector CT for restaging were investigated retrospectively. The split-bolus CT protocol included imaging during the hepatic arterial and portal venous phases in one scan. Software was used for fusion of the independently acquired FDG PET and split-bolus CT data, and fused datasets were compared with FDG PET/unenhanced CT data. The standard of reference for diagnosis of lesions in all patients was a combination of histologic results (if available), clinical results (medical history, physical examination, and laboratory test results), and the results of follow-up imaging (conventional CT, magnetic resonance imaging, and/or ultrasonography) for at least 6 months. Descriptive statistics were used.

RESULTS

Fifty-nine true-positive lesions were identified with fused FDG PET/split-bolus CT; 41 were concordant and detected with both split-bolus CT and PET/unenhanced CT, 16 with split-bolus CT only, and two with PET/unenhanced CT. Two different false-positive lesions were identified with PET/unenhanced CT and PET/split-bolus CT. Furthermore, in 20 of 38 (53%) patients, FDG PET/split-bolus CT allowed detection of important additional findings (n = 40) not detected at FDG PET/unenhanced CT. Both the tumor-related findings (n = 13, 32.5%) and the non-tumor-related findings (n = 27, 67.5%) were important to the clinical treatment of these patients.

CONCLUSION

Fused FDG PET/split-bolus multidetector CT provides additional information compared with FDG PET/unenhanced multidetector CT in oncologic patients.

The dosimetric impact of axillary nodes contouring variability in breast cancer radiotherapy: An AIRO multi-institutional study

AIM

To quantify the dosimetric impact of contouring variability of axillary lymph nodes (L2, L3, L4) in breast cancer (BC) locoregional radiotherapy (RT).

MATERIALS AND METHODS

18 RT centres were asked to plan a locoregional treatment on their own planning target volume (single centre, SC-PTV) which was created by applying their institutional margins to the clinical target volume of the axillary nodes of three BC patients (P1, P2, P3) previously delineated (SC-CTV). The gold standard CTVs (GS-CTVs) of P1, P2 and P3 were developed by BC experts' consensus and validated with STAPLE algorithm. For each participating centre, the GS-PTV of each patient was created by applying the same margins as those used for the SC-CTV to SC-PTV expansion and replaced the SC-PTV in the treatment plan. Datasets were imported into MIM v6.1.7 [MIM Software Inc.], where dose-volume histograms (DVHs) were extracted and differences were analysed.

RESULTS

17/18 centres used intensity-modulated RT (IMRT). The CTV to PTV margins ranged from 0 to 10 mm (median 5 mm). No correlation was observed between GS-CTV coverage by 95% isodose and GS-PTV margins width. Doses delivered to 98% (D98) and 95% (D95) of GS-CTVs were significantly lower than those delivered to the SC-CTVs. No significant difference between SC-CTV and GS-CTV was observed in maximum dose (D2), always under 110%. Mean dose ≥99% of the SC-CTVs and GS-CTVs was satisfied in 84% and 50%, respectively. In less than one half of plans, GS-CTV V95% was above 90%. Breaking down the GS-CTV into the three nodal levels (L2, L3 and L4), L4 had the lowest probability to be covered by the 95% isodose.

CONCLUSIONS

Overall, GS-CTV resulted worse coverage, especially for L4. IMRT was largely used and CTV-to-PTV margins did not compensate for contouring issues. The results highlighted the need for delineation training and standardization.

Does ultrasound provide any added value in breast contouring for radiotherapy after conserving surgery for cancer?

BACKGROUND

Whole breast irradiation after conserving surgery for breast cancer requires precise definition of the target volume. The standard approach uses computed tomography (CT) images. However, since fatty breast and non-breast tissues have similar electronic densities, difficulties in differentiating between them hamper breast volume delineation. To overcome this limitation the breast contour is defined by palpation and then radio-opaque wire is put around it before the CT scan. To optimize assessment of breast margins in the cranial, caudal, medial, lateral and posterior directions, the present study evaluated palpation and CT and determined whether ultrasound (US) provided any added value.

METHODS

Twenty consecutive patients were enrolled after they had provided informed consent to participating in this prospective study which was approved by the Regional Public Health Ethics Committee. Palpation and US defined breast margins and each contour was marked and outlined with a fine plastic wire. Breasts were then contoured on axial CT images using the breast window width (WW) and window level (WL) (401 and 750 Hounsfield Units -HU- respectively), at which setting the plastic wires were invisible. Then, the lung window function (WW 1601 HU; WL -300 HU) was inserted to visualize the plastic wires which were used as guidelines to contour the palpable and US breast volumes. As each wire had a different diameter, both volumes were easily defined on CT slices. Results were analyzed using descriptive statistics, percentage overlap and reproducibility measures (agreement and reliability).

RESULTS

Volumes: US gave the largest and palpation the smallest. Agreement was best between palpation and CT. Reliability was almost perfect in all correlations. Extensions: Cranial and posterior were highest with US and smallest with palpation. Agreement was best between palpation and CT in all extensions except the cranial. Since strong to almost perfect agreement emerged for all comparisons, reliability was high.

CONCLUSIONS

US may be useful in defining the cranial and posterior extensions, mainly when tumours are localized there. This study demonstrates that the now standard radio-opaque wires around the palpable breast may not be needed in breast contouring.

Prostate cancer: contouring target and organs at risk by kilovoltage and megavoltage CT and MRI in patients with and without hip prostheses

OBJECTIVE

In radiotherapy treatment, planning target volume and organs at risk are contoured on kilovoltage CT (kVCT) images. Unlike MR images, kVCT does not provide precise information on target volume extension. Since neither kVCT nor MRI may be suitable for contouring in patients with ferrous hip prostheses, this study evaluated whether megavoltage CT (MVCT) reduced interobserver variability.

METHODS

Two patients without hip prostheses and one patient (Patient 3) with hip prostheses were enrolled. Six radiation oncologists contoured prostate, rectum and bladder on kVCT (Patients 1 and 3), MRI (Patient 2) and MVCT images (Patient 3). MVCT was acquired with fine, normal and coarse modalities. Interobserver variability for each organ was analysed using conformity index (CI) and coefficient of variation (CV).

RESULTS

In patients without hip prostheses, CIs were higher in prostate contouring with MRI than with kVCT, indicating lower interobserver variability with MRI. Very slight variations were seen in rectum and bladder contouring. In the patient with hip prostheses (Patient 3), contouring on kVCT lowered CI and increased CV in the prostate, bladder and rectum. The differences were more marked in the prostate. Only fine modality MVCT reduced interobserver variability and only for the prostate.

CONCLUSION

Even though greater noise and less soft-tissue contrast increase contouring variability with MVCT than with kVCT, lack of artefacts on MVCT could provide better image definition by this modality in hip prosthesis patients in whom MRI is precluded.

ADVANCES IN KNOWLEDGE

We recommend the fine modality MVCT for contouring hip prostheses patients.

Exploring the radiosensitizing potential of AZD8931: a pilot study on the human LoVo colorectal cancer cell line

AIM

To explore the radiosensitizing effect of AZD8931, a novel equipotent and reversible inhibitor of signaling by EGFR (HER1), HER2 and HER3 receptors, focusing on cell cycle progression, apoptosis and clonogenic capacity in the human LoVo colorectal cancer (CRC) cell line, also in comparison with the EGFR-blocking monoclonal antibody Cetuximab or the EGFR tyrosine kinase selective small molecular inhibitor Gefitinib.

MATERIALS AND METHODS

Cells were pretreated with EGFR inhibitors for 5 consecutive days and then exposed or not to ionizing radiation (IR) (2 Gy daily for 3 consecutive days). Cell proliferation, cell cycle progression and apoptosis were evaluated by flow cytometry and enzyme-linked immunosorbent assay (ELISA), clonogenic potential and radiosensitivity were studied by colony formation assay.

RESULTS

AZD8931 induced cell cycle arrest and apoptosis more effectively than Gefitinib and Cetuximab and, more importantly, it was significantly more potent than Gefitinib and Cetuximab in radiosensitizing cells. This radiosensitizing action by AZD8931 mainly occurred by markedly reducing cell cycle progression into S phase, the most radioresistant phase of cell cycle, secondly by inducing apoptosis and reducing clonogenic survival.

CONCLUSIONS

Our results show that AZD8931 increases IR efficacy in LoVo cells, suggesting that it works as a potent radiosensitizer, even more efficient than Gefitinib and Cetuximab, opening new pathways of investigation for further in vitro and in vivo studies aimed at confirming its potential to improve local radiotherapy in CRC.

How radical prostatectomy procedures have changed over the last 10 years in Italy: a comparative analysis based on more than 1500 patients participating in the MIRROR-SIU/LUNA and the Pros-IT CNR study

PURPOSE

Therapeutic strategies for prostate cancer (PCa) have been evolving dramatically worldwide. The current article reports on the evolution of surgical management strategies for PCa in Italy.

METHODS

The data from two independent Italian multicenter projects, the MIRROR-SIU/LUNA (started in 2007, holding data of 890 patients) and the Pros-IT-CNR project (started in 2014, with data of 692 patients), were compared. Differences in patients' characteristics were evaluated. Multivariable logistic regression models were used to identify characteristics associated with robot-assisted (RA) procedure, nerve sparing (NS) approach, and lymph node dissection (LND).

RESULTS

The two cohorts did not differ in terms of age and prostate-specific antigen (PSA) levels at biopsy. Patients enrolled in the Pros-IT-CNR project more frequently were submitted to RA (58.8% vs 27.6%, p < 0.001) and NS prostatectomy (58.4% vs. 52.9%, p = 0.04), but received LND less frequently (47.7% vs. 76.7%, p < 0.001), as compared to the MIRROR-SIU/LUNA patients. At multivariate logistic models, Lower Gleason Scores (GS) and PSA levels were significantly associated with RA prostatectomy in both cohorts. As for the MIRROR-SIU/LUNA data, clinical T-stage was a predictor for NS (OR = 0.07 for T3, T4) and LND (OR = 2.41 for T2) procedures. As for Pros-IT CNR data, GS ≥ (4 + 3) and positive cancer cores ≥ 50% were decisive factors both for NS (OR 0.29 and 0.30) and LND (OR 7.53 and 2.31) strategies.

CONCLUSIONS

PCa management has changed over the last decade in Italian centers: RA and NS procedures without LND have become the methods of choice to treat newly medium-high risk diagnosed PCa.

Fractionated Stereotactic Sequential Boost in a Selected Cohort of Glioblastoma Patients: A Mono-institutional Analysis

AIM

To retrospectively assess toxicity and survival in 15 selected Glioblastoma patients treated with a sequential fractionated stereotactic radiotherapy (FSRT) boost after chemo-radiotherapy (CHT-RT) and compare their survival outcomes with a control group.

PATIENTS AND METHODS

Toxicity was assessed with the CTCAE 3.0 scale. The Kaplan-Meier method was used to design survival curves, log-rank test for bivariate analysis and Cox proportional hazard regression model for multivariate analysis.

RESULTS

The median follow-up was 16 months (range=5-60). One case of headache and one of radionecrosis (RN) occurred. Median overall survival (OS) was 25 months in the boost group vs. 14 in the no-boost group (p=0.004). Median progression-free survival (PFS) was 15 months in the boost group versus 8 in the no-boost group (p=0.046). At multivariate analysis FSRT boost resulted significantly associated with OS and PFS.

CONCLUSION

In our series a sequential FSRT boost resulted in safe outcomes and significantly associated with survival.

Acute and late toxicities after moderate hypo-fractionated radiation therapy to the chest wall/breast and regional lymph nodes: a retrospective observational study

BACKGROUND

Still controversial is the optimal radiotherapy (RT) schedule for high-risk patients after mastectomy or breast conserving surgery (BCS). An alternative to conventional RT schedules is hypo-fractionation (HF) (40.5 Gy or 42.67 Gy in 15-16 fractions). The present observational, retrospective study assessed acute and late toxicities after hypo-fractionation targeting the chest wall/breast and regional lymph nodes, compared with a cohort that had received conventional fractionation. The aim was to establish the safety of hypo-fractionation in wide-field irradiation.

MATERIALS AND METHODS

This study enrolled 80 patients (median age 63 years; range 34-83) who underwent either BCS (9) or mastectomy (71) as well as axillary lymph node dissection. The RT schedule was 40.05 Gy in 15 fractions over 3 weeks. A simultaneous integrated boost (SIB) (49.5 Gy in 15 fractions) was delivered to the tumour bed in 9 patients who received whole breast irradiation (WBI). Acute and late toxicities were graded according to Common Terminology Criteria for Adverse Events (CTCAE v4.02) and compared with outcomes in 51 patients after conventionally fractionated RT to the chest wall/breast and regional nodes. Median follow-up was 16 months (range 2.7-33.8 months).

RESULTS

All patients completed RT with no toxicity-related interruption. No patient developed any cardiac or pulmonary toxicity or ≥ grade 3 acute skin and oesophageal toxicity. Late G1 skin toxicity occurred in 9/75 patients who were eligible for analysis. No patient developed ≥ G2 late toxicity. The incidences of acute toxicity, skin rash and dysphagia were significantly lower after HF (p < 0.001 and 0.040, respectively). No significant differences emerged in late edema and skin toxicity.

CONCLUSIONS

The efficacy and safety of hypofractionated regimens were confirmed in real-life settings. Present evidence supports the use of HFRT as standard treatment, providing patients with the advantages of shorter treatment times and reduced healthcare costs.

The waiting time for prostate cancer treatment in Italy: analysis from the PROS-IT CNR Study

BACKGROUND

Prostate cancer (PCa) is the second most common neoplasm in male patients. To date, there's no certain indication about the maximum waiting time (WT) acceptable for treatment beginning and the impact on oncological and functional outcomes has not been well established.

METHODS

Data from the National Research Council PCa monitoring multicenter project in Italy (Pros-IT CNR) were prospectively collected and analyzed. WT was defined as the time from the bioptical diagnosis of PCa to the first treatment received. Patients were divided in two groups, using a time frame of 90 days. Quality of life was measured through the Italian version of the University of California Los Angeles-Prostate Cancer Index (UCLA-PCI) and of the Short-Form Health Survey (SF-12). The occurrence of upgrading, upstaging, presence of lymph node metastasis and positive surgical margins at the final histopathological diagnosis, and PSA at 12 months follow-up were evaluated.

RESULTS

The overall median WT was 93 days. The logistic multivariable model confirmed that age, being resident in Southern regions of Italy and T staging at diagnosis were significantly associated with a WT>90 days. At 6 months from diagnosis the mean SF-12 score for the emotional-psychological component was significantly lower in WT≥90 days group (P=0.0428). Among patients treated with surgical approach, no significant differences in oncological outcomes were found in the two groups.

CONCLUSIONS

In our study age, clinical T stage and provenance from Southern regions of Italy are associated with a WT>90 days. WT might have no impact on functional and oncological outcome.

Effect of internal port on dose distribution in post-mastectomy radiotherapy for breast cancer patients after expander breast reconstruction

BACKGROUND

In patients with expander-based reconstruction a few dosimetric analyses detected radiation therapy dose perturbation due to the internal port of an expander, potentially leading to toxicity or loss of local control. This study aimed at adding data on this field.

MATERIALS AND METHODS

A dosimetric analysis was conducted in 30 chest wall treatment planning without and with correction for port artifact. In plans with artifact correction density was overwritten as 1 g/cm3. Medium, minimum and maximum chest wall doses were compared in the two plans. Both plans, with and without correction, were compared on an anthropomorphic phantom with a tissue expander on the chest covered by a bolus simulating the skin. Ex vivo dosimetry was carried out on the phantom and in vivo dosimetry in three patients by using film strips during one treatment fraction. Estimated doses and measured film doses were compared.

RESULTS

No significant differences emerged in the minimum, medium and maximum doses in the two plans, without and with correction for port artifacts. Ex vivo and in vivo analyses showed a good correspondence between detected and calculated doses without and with correction.

CONCLUSIONS

The port did not significantly affect dose distribution in patients who will receive post-mastectomy radiation therapy.

The 2024 Assisi think tank on breast cancer: Focus on the use of a tumour bed boost after breast conserving therapy

At the Fifth Assisi Think Tank Meeting (ATTM) on breast cancer, one key topic was the role of tumor bed boost in invasive breast cancer and ductal carcinoma in situ. The need for a tumor bed boost after whole breast irradiation is controversial. A literature review assessed boost indications, target volume definition, techniques, dose fractionation, and ongoing trials. Findings indicated that while a boost halves the risk of local recurrence at 10 years, it also leads to worsened cosmetic outcomes and increased fibrosis without improving overall survival. Therefore, we would recommend to omit the boost if the estimated reduction in local recurrence at 10 years is less than 3 %, and to apply shared decision-making with patients, if the boost is expected to reduce the local recurrence rate with >3 % at 10 years. Future research will focus on identifying patient subgroups that can safely omit the boost and improving boost volume precision.

Single-phase Whole-body 64-MDCT Split-bolus Protocol for Pediatric Oncology: Diagnostic Efficacy and Dose Radiation

PURPOSE

To evaluate the image quality and the diagnostic efficacy by single-phase whole-body 64-slice multidetector CT (MDCT) for pediatric oncology.

PATIENTS AND METHODS

Chest-abdomen-pelvis CT examinations with single-phase split-bolus technique were evaluated for T: detection and delineation of primary tumor (assessment of the extent of the lesion to neighboring tissues), N: regional lymph nodes and M: distant metastasis. Quality scores (5-point scale) were assessed by two radiologists on parenchymal and vascular enhancement.

RESULTS

Accurate TNM staging in term of detection and delineation of primary tumor, regional lymph nodes and distant metastasis was obtained in all cases. On the image quality and severity artifact, the Kappa value for the interobserver agreement measure obtained from the analysis was 0.754, (p<0.001), characterizing a very good agreement between observers.

CONCLUSION

Single-pass total body CT split-bolus technique reached the highest overall image quality and an accurate TNM staging in pediatric patients with cancer.

Integrating stereotactic radiotherapy and systemic therapies

This paper focuses on stereotactic radiotherapy (SRT ) interactions with targeted therapies and immune system modulating agents because SRT inevitably interacts with them in the treatment of oligometastatic patients. Radiation oncologists need to be aware of the advantages and risks of these interactions which can, on one hand, enhance the effect of therapy or, on the other, potentiate reciprocal toxicities. To date, few prospective studies have evaluated the interactions of SRT with new-generation drugs and data are mainly based on retrospective experiences, which are often related to small sample sizes.

Early results of PRO-EPI: PROspective multicenter observational study on elective pelvic nodes irradiation in patients with intermediate/high/very high-risk non-metastatic prostate cancer submitted to radical, adjuvant, or salvage radiotherapy with or without concomitant androgen deprivation therapy

Simple Summary: Although radiotherapy plays a fundamental role in the management of intermediate/high/very high-risk non-metastatic prostatic cancer (IHR-nmPca), there is still no consensus on the optimal treatment strategy in this setting. Remarkably, the role of elective nodal irradiation (ENI) is still highly controversial. The PROspective multicenter observational study on Elective Pelvic nodes Irradiation (PRO-EPI) was designed to provide "real life" data regarding the patterns of care for IHR-nmPca. Forty-three Italian Radiation Oncology centers participated in the PROspective multicenter observational study on Elective Pelvic nodes Irradiation (PRO-EPI) project, with 1029 patients enrolled. In this preliminary analysis, we longitudinally evaluated the impact of Elective Nodal Irradiation (ENI) and radiotherapy features on toxicity and quality of life (QoL). Six months follow-up data were available for 913 patients and 12 months data for 762 patients. Elective Nodal Irradiation was given to 506 patients (48.9%). Volumetric Intensity-Modulated Radiation Therapy (IMRT) was adopted in more than 77% of patients and Image-Guided Radiation Therapy (IGRT) in 84.4%. Androgen deprivation therapy (ADT) was administered to the majority of patients (68.3%), and it was associated to ENI in 408 cases (81.1%). Toxicity was mostly mild and reversible and IGRT resulted in a significant reduction of rectal toxicity, although a non-significant trend toward increased urinary toxicity was observed. No statistically significant differences in QoL and toxicity were seen in patients treated with or without ENI. The adoption of IGRT is widespread and increasing and could reduce treatment toxicity. ENI is not yet the standard treatment, but it is performed in a growing fraction of cases and not resulting into an increase in toxicity or in a deterioration of QoL. Further analyses are needed to clarify the long-term toxicity profile and the impact of ENI on survival.

A systematic review and meta-analysis of intraoperative electron radiation therapy delivered with a dedicated mobile linac for partial breast irradiation in early breast cancer

• PBI is valid alternative to WBI in patients at low-risk of local relapse. • PBI is delivered by means of various techniques, one of which is IOeRT. • After IOeRT, an unexpectedly high LR rate was observed in the only phase III RCT. • Patient selection impacts on LR rates after IOeRT. • With appropriate patient selection IOeRT outcomes overlap with other RT techniques.

The 2022 Assisi Think Tank Meeting: White paper on optimising radiation therapy for breast cancer

The present white paper, referring to the 4th Assisi Think Tank Meeting on breast cancer, reviews state-of-the-art data, on-going studies and research proposals. <70% agreement in an online questionnaire identified the following clinical challenges: 1: Nodal RT in patients who have a) 1-2 positive sentinel nodes without ALND (axillary lymph node dissection); b) cN1 disease transformed into ypN0 by primary systemic therapy and c) 1-3 positive nodes after mastectomy and ALND. 2. The optimal combination of RT and immunotherapy (IT), patient selection, IT-RT timing, and RT optimal dose, fractionation and target volume. Most experts agreed that RT- IT combination does not enhance toxicity. 3: Re-irradiation for local relapse converged on the use of partial breast irradiation after second breast conserving surgery. Hyperthermia aroused support but is not widely available. Further studies are required to finetune best practice, especially given the increasing use of re-irradiation.

MRI-derived radiomics to guide post-operative management of glioblastoma: Implication for personalized radiation treatment volume delineation

BACKGROUND

The glioblastoma's bad prognosis is primarily due to intra-tumor heterogeneity, demonstrated from several studies that collected molecular biology, cytogenetic data and more recently radiomic features for a better prognostic stratification. The GLIFA project (GLIoblastoma Feature Analysis) is a multicentric project planned to investigate the role of radiomic analysis in GB management, to verify if radiomic features in the tissue around the resection cavity may guide the radiation target volume delineation.

MATERIALS AND METHODS

We retrospectively analyze from three centers radiomic features extracted from 90 patients with total or near total resection, who completed the standard adjuvant treatment and for whom we had post-operative images available for features extraction. The Manual segmentation was performed on post gadolinium T1w MRI sequence by 2 radiation oncologists and reviewed by a neuroradiologist, both with at least 10 years of experience. The Regions of interest (ROI) considered for the analysis were: the surgical cavity ± post-surgical residual mass (CTV_cavity); the CTV a margin of 1.5 cm added to CTV_cavity and the volume resulting from subtracting the CTV_cavity from the CTV was defined as CTV_Ring. Radiomic analysis and modeling were conducted in RStudio. Z-score normalization was applied to each radiomic feature. A radiomic model was generated using features extracted from the Ring to perform a binary classification and predict the PFS at 6 months. A 3-fold cross-validation repeated five times was implemented for internal validation of the model.

RESULTS

Two-hundred and seventy ROIs were contoured. The proposed radiomic model was given by the best fitting logistic regression model, and included the following 3 features: F_cm_merged.contrast, F_cm_merged.info.corr.2, F_rlm_merged.rlnu. A good agreement between model predicted probabilities and observed outcome probabilities was obtained (p-value of 0.49 by Hosmer and Lemeshow statistical test). The ROC curve of the model reported an AUC of 0.78 (95% CI: 0.68-0.88).

CONCLUSION

This is the first hypothesis-generating study which applies a radiomic analysis focusing on healthy tissue ring around the surgical cavity on post-operative MRI. This study provides a preliminary model for a decision support tool for a customization of the radiation target volume in GB patients in order to achieve a margin reduction strategy.

Association of 99mTc-MIBI brain SPECT and proton magnetic resonance spectroscopy (1H-MRS) to assess glioma recurrence after radiotherapy

AIM

The aim of this study was to compare 99mTc-MIBI brain SPECT and proton magnetic resonance spectroscopy (1H-MRS) findings and to evaluate their association.

METHODS

Both exams were performed on 30 glioma patients, previously operated and treated with radiotherapy, having MRI doubtful between recurrence and radiotherapy effects. SPECT images were acquired 15 minutes after radiopharmaceutical administration with a dual-head gamma camera. T1/B1 uptake ratio was calculated between a tumor ROI (T1) and a normal mirror symmetric ROI (B1) and T2/B2 ratio was obtained between a ROI in the hottest neoplastic part (T2) and a normal mirror symmetric ROI (B2). 1H-MRS was performed using a 1.5 T system equipped with a spectroscopy package. SPECT and 1H-MRS data were compared with histology after new surgery or with follow-up.

RESULTS

SPECT and 1H-MRS showed recurrence in 18 patients (confirmed by biopsy, coinciding only in 17 cases) and were negative in 10 (1 false negative). SPECT and 1H-MRS disagreed in 2 cases of recurrence (1 diagnosed by brain SPECT, 1 by 1H-MRS). T1/B1 ratio mean value (4.26+/-2.5) was significantly lower than T2/B2 (4.93+/-2.81; P<0.001). SPECT and 1H-MRS sensitivity in detecting recurrence was 90%, specificity 100%, accuracy 93%, negative predictive value (NPV) 83% and positive predictive value (PPV) 100%; the associated exams sensitivity was 95%, specificity 100%, accuracy 96.6%, NPV 90.9%, PPV 100%.

CONCLUSIONS

Brain SPECT and 1H-MRS have equivalent values of diagnostic parameters in differentiating tumor recurrence and radiation effects, and their association might provide additional information.

Biomarker-Directed Radiotherapy in Breast Cancer: A Narrative Review

Importance

Integration of molecular biomarker information into systemic therapy has become standard practice in breast cancer care. However, its implementation in guiding radiotherapy (RT) is slower. Although postoperative RT is recommended for most patients after breast-conserving surgery and, depending on risk factors, following mastectomy, emerging evidence has indicated that patients with low scores on gene expression signatures or selected clinical-pathological features may have very low local recurrence rates. This narrative review explored the potential of biomarker-directed personalized RT approaches, which may optimize treatment strategies and be associated with improved patient outcomes and experiences.

Observations

Distinctions between prognostic and predictive biomarkers were highlighted, emphasizing the importance of analytical and clinical validity in biomarker-based studies. Findings from studies investigating the prognostic and predictive value of various genomic signatures and immunohistochemical markers for guiding breast RT were presented. These included the Adjuvant Radiotherapy Intensification Classifier and the Profile for the Omission of Local Adjuvant Radiation, which have shown potential in predicting RT benefits. The genomic-adjusted radiation dose and role of tumor-infiltrating lymphocytes were also discussed. Ongoing clinical trials exploring the use of biomarkers in ductal carcinoma in situ and invasive breast cancer to refine RT decision-making were illustrated.

Conclusions and Relevance

The results of this narrative review suggest that evidence-based shared decision-making is crucial to optimize treatment according to the individual's predicted benefits and risks along with their personal preferences. Incorporation of biomarker-directed approaches in RT for breast cancer may hold promise for personalized treatment, potentially facilitating omission of RT for patients at low risk of recurrence, while identifying those who may benefit from intensified therapy. This personalized RT approach may be associated with improved clinical outcomes and quality of life and facilitate decision-making for people with breast cancer. However, there remains a need for robust clinical and analytical validation of biomarkers to ensure reliability and clinical utility for RT optimization.