Daily Fractions Research Articles

Daily Head and Neck Treatment Assessment for Optimal Proton Therapy Planning Robustness.

Robust optimization in proton therapy ensures adequate target coverage; however, validation of fractional plan quality and setup uncertainty in patients has not been performed. We aimed to assess plan robustness on delivered head and neck proton plans classified into two categories: (1) primary only (PO) and (2) primary and neck nodal (PNN) coverage. Registration at the machine was utilized for daily CBCT to generate a synthetic CT. The dose for the clinical target volume (CTV) and organs at risk (OAR) was compared to the expected robustness bands using 3.5% range uncertainty and 3 mm vs. 5 mm setup uncertainty. The fractional deviation was defined as D95% and V100% outside of uncertainty constraints. About 203 daily fractions from 6 patients were included for analysis. The percentage of fractions that exceeded robustness calculations was greater in 3 mm as compared to 5 mm setup uncertainty for both CTV and OAR volumes. PO plans had clinically insignificant average fractional deviation, less than 1%, in delivered D95% and V100%. In comparison, PNN plans had up to 2.2% average fractional deviation in delivered V100% using 3 mm robustness. Given the need to balance dose accuracy with OAR sparing, we recommend the utilization of 3 mm setup uncertainty as an acceptable simulation of the dose delivered.

Efficacy of stereotactic radiation therapy for the treatment of confirmed or presumed canine glioma.

Intracranial gliomas are the second most common brain tumour in dogs. Radiation therapy provides a minimally invasive treatment option for this tumour type. Earlier publications reporting on the use of non-modulated radiation therapy suggested a poor prognosis for dogs with glioma, with median survival times ranging between 4 and 6 months; more recent literature utilizing stereotactic radiation therapy (SRT) demonstrates that the prognosis for canine gliomas may be more promising, with survival times closer to 12 months. A single institution retrospective study was performed between 2010 and 2020 investigating the outcomes of dogs with biopsy-confirmed glioma or a presumptive diagnosis of intra-cranial glioma based on MRI characteristics that were treated with SRT. Twenty-three client-owned dogs were included. Brachycephalic breeds were overrepresented, totalling 13 dogs (57%). SRT protocols included 16 Gy single fraction (n = 1, 4%), 18 Gy single fraction (n = 1, 4%), 24 Gy in 3 daily fractions (n = 20, 91%), or 27 Gy in four daily fractions (n = 1, 4%). Twenty-one dogs (91%) had improvement of their presenting clinical signs following SRT. Median overall survival time (MST) was 349 days (95% CI, 162-584). Median disease specific survival time was 413 days (95% CI, 217-717). When SRT is incorporated into the management plan for dogs with confirmed or presumed intracranial glioma, a median survival time of approximately 12 months may be achievable.

Radioterapija raka dojke - promjene u shemama frakcioniranja kroz desetljeća

Traditionally, as a standard dose fractionation schedule, adjuvant radiotherapy for breast cancer has been performed using prescribed doses of 46–50 Gy divided into daily fractions of 1.8–2 Gy. Overall, radiotherapy treatment took 5 weeks. In the 1990s, schedules using higher daily doses (2.5–3 Gy), a smaller number of fractions (hypofractionation), and a reduced overall prescribed dose started in the context of clinical trials. First results revealed an equivalent cosmetic effect of hypofractionated protocols compared to standard fractionation, and after longer follow-up, hypofractionation was connected with better control of the disease. Hypofractionation started to be considered the new treatment standard. Results of newer clinical trials confirm the efficacy and safety of adjuvant breast cancer radiotherapy lasting 5 working days using daily fractions of 5.2 Gy in certain subgroups of breast cancer patients.

Optimizing surface mould brachytherapy for treatment of nasal basal cell carcinoma using customized applicators

PURPOSESurface mould brachytherapy (SMBT) is ideal in treating superficial skin cancer over the curved surface of the nasal ala. We describe the process of initiating and optimizing SMBT treatment at our institution including clinical workflow, generation of three dimensional (3D) printed custom applicators, and clinical outcomes. METHODS AND MATERIALSPlanning CT scans were used to acquire images for delineating target volumes. The applicator was designed with customized catheter positioning (3–5mm from target) to cover target volume while sparing dose to organs at risk (OAR) such as adjacent skin and nasal mucosa. Applicators were 3D printed, with transparent resin to aid visualization of underlying skin. Dosimetric parameters evaluated included CTV D90, CTV D0.1cc, and D2cc to OARs. Clinical outcomes assessed were local control, acute and late toxicity (Common Terminology Criteria for Adverse Events v5.0 [CTCAEv5.0]), and cosmesis (Radiation Therapy Oncology Group [RTOG]). RESULTSTen patients were treated with SMBT with a median followup of 17.8 months. Dose prescription was 40 Gy in 10 daily fractions. Mean CTV D90 was 38.5 Gy (range 34.7–40.6), mean CTV D0.1cc 49.2 Gy (range 45.6–53.5), which was <140% of the prescription dose in all patients. Treatment was well tolerated, with acceptable Grade 2 acute, Grade 0–1 late skin toxicity, and good-excellent cosmesis for all patients. Two patients experienced local failure, and both underwent surgical salvage. CONCLUSIONSSMBT was successfully planned and delivered for superficial nasal BCC using 3D printed custom applicators. Excellent target coverage was achieved while minimizing dose to OAR. Toxicity and cosmesis rates were good-excellent.

Short-course radiotherapy for rectal cancer: real-world evidence in Argentina.

Short-course radiotherapy (SCRT) of 25 Gy in five daily fractions is a recommended strategy in the neoadjuvant setting for resectable locally advanced rectal cancer (LARC), as well as in cases of metastatic disease for local control. There is scarce information regarding the use of SCRT for patients who have received nonoperative management. To describe the characteristics of patients who received treatment with SCRT for LARC and metastatic rectal cancer, toxicity, and the approach after radiation treatment. This is a retrospective analysis of all patients who underwent SCRT for rectal cancer at the Alexander Fleming Institute from March 2014 to June 2022. In total, 44 patients were treated with SCRT. The majority were male (29, 66%), with a median age of 59 years (interquartile range 46-73). Most patients had stage IV disease (26, 59.1%), followed by LARC (18, 40.9%). Most lesions were located in the middle rectum (30, 68%). The majority of LARC patients underwent SCRT followed by consolidation chemotherapy (ChT) (16/18, 89%), while most patients with metastatic disease underwent SCRT followed by consolidation ChT (14/26, 53.8%). A clinical complete response (cCR) was documented in 8/44, 18.2% of patients. Most patients with LARC and cCR were managed by a watch and wait approach (5/18, 27.7%). Local recurrence was observed in LARC cases (2/18, 11.1%). Patients who underwent SCRT following consolidation ChT were more likely to have adverse events (AEs) than those undergoing induction ChT following SCRT (11/30, 36.7% versus 3/12, 25%, p = 0.02). In a subgroup of patients diagnosed with LARC and treated with SCRT followed by ChT, surgical treatment could be omitted after they achieved a cCR. Local recurrence was similar to that reported in a previous study. SCRT is a reasonable option for local disease control in stage IV disease, yielding low toxicity rates. Therefore, decisions must be made by a multidisciplinary team. Prospective studies are necessary to reach further conclusions.

Stereotactic body radiation therapy with sequential immunochemotherapy as neoadjuvant therapy in resectable non-small cell lung cancer (SACTION-01 study).

8540 Background: Neoadjuvant PD-1 inhibitor plus chemotherapy increases pathological response for resectable non-small cell lung cancer (NSCLC) compared with chemotherapy alone. Previous phase II trial indicated that stereotactic body radiation therapy (SBRT) served as an immunomodulator and enhanced the effect of preoperative immuno-monotherapy. However, whether SBRT would further increase the efficacy of immunochemotherapy for NSCLC remains unknown. Methods: In this phase II trial, patients with resectable EGFR wild-type stage IIA to IIIB NSCLC were recruited to receive SBRT (24 Gy in 3 daily fractions) to the primary tumor followed by two cycles of PD-1 inhibitor tislelizumab (200 mg) plus platinum-based doublet chemotherapy (Q3W) before surgical resection. The primary endpoint was major pathological response (MPR) defined as no more than 10% of viable tumor cells in the specimen. Simon’s optimal two-stage design was used for conducting the trial. The null hypothesis was that the MPR rate is 0.30, and the alternative hypothesis was that the true MPR rate was 0.50. More than 4 MPRs were needed in stage 1 (n=15) to continue, and if there were 19 or more MPRs in 46 patients by the end of stage 2, the null hypothesis can be rejected. The design controls the type I error rate at 0.05 and yields the power of 0.80. (NCT05319574). Results: Between May 2022 and Jan 2023, 32 patients were enrolled with 31 (96.9%) male and 19 (59.4%) having squamous cell lung cancer. Twenty-six (81.3%) patients had stage IIIA/B disease. All patients received at least one cycle of immunochemotherapy; 23 of the 25 patients (92.0%) who completed treatment had undergone R0 resections, except for one patient who had disease progression and the other one that unable to tolerate surgery because of grade 4 neutropenia. Twenty-two patients underwent minimally invasive approaches and 3 of them (13.6%) converted to thoracotomy. The median percentage of the viable tumor was 0 (interquartile range: 0-4.0%). Twenty patients achieved MPR, which surpassed the prespecified required number to reject the null hypothesis, resulting in the MPR rate of 80.0% (20/25) in the intention-to-treat population, and 87.0% (20/23) in the per-protocol population. Pathological complete response (pCR) was found in 14 patients (56.0% in the intention-to-treat population and 60.9% in the per-protocol population). Nodal clearance status (pN0) was found in 20 of 23 cN1/2 cases (87.0%). Grade 3-4 adverse events related to neoadjuvant treatment included neutropenia (13.0%), anemia (4.3%), and pneumonia (4.3%). No 30-day or 90-day mortality was observed. Conclusions: Neoadjuvant SBRT followed by immunochemotherapy yields unprecedently high MPR and pCR rates in NSCLC without EGFR mutation. The trial will continue to recruit 14 more patients to reach a final sample size of 46 participants. Clinical trial information: NCT05319574 .

Pre-pubertal accelerometer-assessed physical activity and timing of puberty in British boys and girls: the Millennium Cohort Study.

Early puberty timing is associated with adverse health outcomes. We aimed to examine prospective associations between objectively measured physical activity and puberty timing in boys and girls. In the UK Millennium Cohort Study, physical activity volume and intensities at 7 years were measured using accelerometers. Status of several pubertal traits and age at menarche were reported at 11, 14 and 17 years. Age at menarche in girls was categorized into tertiles. Other puberty traits were categorized into earlier or later than the median ages calculated from probit models, separately in boys and girls. Multivariable regression models, with adjustment for maternal and child characteristics including body mass index (BMI) at age 7 years as potential confounders, were performed to test the associations of total daily activity counts and fractions of activity counts across intensities (in compositional models) with puberty timing, separately in boys (n = 2531) and girls (n = 3079). Higher total daily activity counts were associated with lower risks for earlier (vs later) growth spurt, body hair growth, skin changes and menarche in girls, and more weakly with lower risks for earlier skin changes and voice breaking in boys (odds ratios = 0.80-0.87 per 100 000 counts/day). These associations persisted on additional adjustment for BMI at 11 years as a potential mediator. No association with puberty timing was seen for any physical activity intensity (light, moderate or vigorous). More physical activity regardless of intensity may contribute to the avoidance of earlier puberty timing, independently of BMI, particularly in girls.

Hypofractionated radiotherapy for invasive squamous cell carcinoma of the scalp in the elderly: Efficacy and tolerance, preliminary results

PurposeSkin squamous cells carcinomas (SCC) are frequently tumor, especially in the elderly population. Surgical excision is the standard treatment. But for patients suffering large tumor or/with comorbidity, a conservative approach with irradiation can be proposed. The hypofractionated schedule is used to shorten the overall treatment time with same results and without compromising therapeutic outcomes. The aim of this study is to assess the efficacy and tolerance of hypofractionated radiotherapy for invasive SCC of the scalp in elderly. Patients and methodsWe included patients suffering from SCC of the scalp and treated by hypofractionated radiotherapy at the Institut de cancérologie de Lorraine or centre Émile-Durkeim d’Épinal, from January 2019 to December 2021. Characteristics of patients, size of the lesion and side effects were collected retrospectively. Tumor size at 6 months corresponded to the primary endpoint. Toxicity was collected for the secondary endpoint. ResultsTwelve patients with a median age of 85 years old were included. The mean size was 4,5cm with a bone invasion in 2/3 of cases. Radiotherapy was delivered after surgical excision for half of the patient. The dose delivered was 54Gy in 18 daily fractions size. Six months after irradiation: 6/11 patients had no residual lesion, 2/11 had a partial response with a residual lesion of about 1cm. 3 patients presented local recurrence. One patient died within 6 months of radiotherapy because of another comorbidity. In total, 25% had presented a grade 3 acute radiation dermatitis, no grade 4 toxicity. ConclusionShort term of moderately hypofractionated schedule radiotherapy was a success with complete or partial response for more than 70% of the patients in squamous cell carcinomas. There is no major side effect.

Stereotactic body radiotherapy for spine metastases: a review of 24 Gy in 2 daily fractions.

Stereotactic body radiotherapy (SBRT) has proven to be a highly effective treatment for selected patients with spinal metastases. Randomized evidence shows improvements in complete pain response rates and local control with lower retreatment rates favoring SBRT, compared to conventional external beam radiotherapy (cEBRT). While there are several reported dose-fractionation schemes for spine SBRT, 24 Gy in 2 fractions has emerged with Level 1 evidence providing an excellent balance between minimizing treatment toxicity while respecting patient convenience and financial strain. We provide an overview of the 24 Gy in 2 SBRT fraction regimen for spine metastases, which was developed at the University of Toronto and tested in an international Phase 2/3 randomized controlled trial. The literature summarizing global experience with 24 Gy in 2 SBRT fractions suggests 1-year local control rates ranging from 83-93.9%, and 1-year rates of vertebral compression fracture ranging from 5.4-22%. Reirradiation of spine metastases that failed prior cEBRT is also feasible with 24 Gy in 2 fractions, and 1-year local control rates range from 72-86%. Post-operative spine SBRT data are limited but do support the use of 24 Gy in 2 fractions with reported 1-year local control rates ranging from 70-84%. Typically, the rates of plexopathy, radiculopathy and myositis are under 5% in those series reporting mature follow up, with no cases of radiation myelopathy (RM) reported in the de novo setting when the spinal cord avoidance structure is limited to 17 Gy in 2 fractions. However, re-irradiation RM has been observed following 2 fraction SBRT. More recently, 2-fraction dose escalation with 28 Gy, with a higher dose constraint to the critical neural tissues, has been reported suggesting improved rates of local control. This regimen may be important in those patients with radioresistant histologies, high grade epidural disease, and/or paraspinal disease. The dose-fractionation of 24 Gy in 2 fractions is well-supported by published literature and is an ideal starting point for centers looking to establish a spine SBRT program.

OCCIPITAL BONE METASTASIS REVEALING A PAPILLARY THYROID CARCINOMA: CASE REPORT

A 45-years-old manwas diagnosed with occipital bone metastasis of papillary thyroid carcinoma. He presented an eight cm occipital bone mass with two years of evolution. The CT scan showed an81,3 x 52,7 x 61 mmtumour of occipital bone with meningeal, brain and soft tissue invasion. The biopsy confirmed thyroid origin of the mass.Three other osteolytic lesions were noted: left ischium, D4 and L1 with medullary canal invasion.He received a total dose of 20Gy of conformal 3D radiotherapy in 5 fractions, at a daily dose fraction of 4Gy over one week to the four lesions.

Abstract 2412: MET inhibition enhances the effect of radiation in MET dysregulated non-small cell lung cancer models

Abstract Objective: Alterations in the MET receptor are seen in up to 10% of patients with non-small cell lung cancer (NSCLC). A mutation in exon 14, which results in deletion of the intracellular juxtamembrane domain of the receptor, leading to enhanced signaling, is the most common MET mutation in NSCLC. MET is involved in multiple pathways associated with apoptosis and radiation response. We investigated the effects of inhibiting MET with capmatinib, a potent and clinically relevant ATP-competitive kinase inhibitor, in combination with radiation in MET-dependentNSCLC models. Methods: MET exon 14 mutated and MET amplified NSCLC cell lines treated with radiation or capmatinib were assessed with proliferation, clonogenic survival, apoptosis, and DNA damage signaling and repair assays. MET signaling proteins were evaluated by Western blotting. In vivo growth responses to the MET inhibitor capmatinib with and without radiation were evaluated in patient derived xenograft (PDX) models established from both MET amplified and MET exon 14 skipping mutation containing patient tumors. Radiation was delivered in 10 daily fractions of 2 Gy and capmatinib was administered by oral gavage daily 1 hour prior to radiation at a dose 20 mg/kg for capmatinib. Immunohistochemistry (IHC) was performed to evaluate MET signaling and proliferation. Results: Radiation increased the expression and capmatinib inhibited phospho-AKT, phospho-s6,phospho-ERK, and phospho-STAT3 in our MET-driven NSCLC cell lines. Combination of capmatinib and radiation in clonogenic assays increased sensitivity to radiation in MET dysregulated cell lines. No radiation-enhancing effect was observed in MET wild-type and human bronchial epithelial cell lines. Campatinib alone significantly inhibited tumor growth in both ourMET exon 14 mutated and MET amplified xenograft models (p&amp;lt;0.01). Combination of capmatinib and radiation significantly delayed growth compared to vehicle control, capmatinib alone or radiation alone (p&amp;lt;0.01). IHC demonstrated inhibition of phospho-MET and phospho-S6 and a decrease in Ki67 with inhibition of MET. A significant decrease Ki67 proliferation was observed in the combination arm compared to radiation along or drug alone. Conclusion:Inhibition of MET enhanced the effect of radiation in multiple MET-altered NSCLC PDX models.Additional studies are currently underway evaluating the mechanisms of radiation sensitization with a focus on MET-induced apoptosis. Citation Format: Shrey K. Ramesh, Saahil N. Javeri, Kwangok P. Nickel, Ahmet Cifci, Rachel L. Minne, Randall J. Kimple, Andrew M. Baschnagel. MET inhibition enhances the effect of radiation in MET dysregulated non-small cell lung cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2412.

Abstract 2817: Combining the RCAS/TVA retrovirus system and a conditional oncohistone H3.3K27M allele to investigate radiosensitization strategies in primary mouse models of diffuse midline glioma

Abstract Diffuse midline gliomas (DMGs) are deadly brain tumors characterized by inactivating TP53 mutations and oncohistone H3.3K27M mutations. One potential strategy to improve outcomes for DMG patients is to inhibit Ataxia-telangiectasia mutated kinase (ATM), an orchestrator of the cellular response to the DNA double-strand breaks. Previous research showed that Atm inactivation strongly enhanced the efficacy of radiation therapy for primary mouse models of p53-inactivated DMG. However, it remained unclear whether Atm inactivation would also radiosensitize DMGs driven by both p53 loss and by H3.3K27M mutation. To induce primary DMGs driven by p53 deletion and H3.3K27M expression in a lineage-controlled manner, we leveraged the RCAS/TVA retrovirus system and a conditional loxP-Stop-loxP-H3f3a-K27M-Tag allele. We delivered retroviruses carrying (i) the oncogene platelet-derived growth factor B (PDGFB), (ii) Cre recombinase, and (iii) luciferase into the brainstems of pups with genotype Nestin-TVA, p53-FL/FL, loxP-Stop-loxP-H3f3a-K27M-Tag/+; Atm-FL/FL. In these mice, RCAS retroviruses specifically transduce TVA-expressing Nestin+ neural stem cells to drive primary brain tumors in which Cre recombinase induces H3.3K27M-Tag and inactivates both p53 and Atm. Mice were imaged bi-weekly through in vivo luciferase imaging until a tumor signal was detected. Mice then received 3 daily fractions of 10 Gy focal brain irradiation. Mice were monitored for survival and immunohistochemistry (IHC) was used to confirm appropriate expression or loss of different gene products. Preliminary analyses revealed similar time to tumor formation for these mice compared to littermate controls with intact ATM expression in their tumors (Atm-FL/+). Additionally, Kaplan-Meier survival analysis revealed a significant increase in post-radiation median overall survival for these mice compared to the controls with intact tumoral ATM expression. Overall, these data suggest that (i) the RCAS/TVA system can be combined with a unique conditional allele to generate primary DMGs bearing H3.3K27M in mice, (ii) Atm loss in the tumor cells does not appreciably affect tumor formation in these models, and (iii) Atm loss still significantly radiosensitizes p53-mutant tumors even in the presence of H3.3K27M. These results nominate ATM-directed therapies for further investigation as radiosensitizers in patients with TP53/H3.3K27M-mutant DMG. Citation Format: Sophie R. Wu, María E. Guerra Garcia, Harrison Liu, Nerissa T. Williams, Lixia Luo, Yan Ma, David G. Kirsch, Zachary J. Reitman. Combining the RCAS/TVA retrovirus system and a conditional oncohistone H3.3K27M allele to investigate radiosensitization strategies in primary mouse models of diffuse midline glioma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2817.

Effects of drought stress treatment on phytochemical contents of strawberry varieties

Drought is nowadays a significant environmental factor limiting plant quality and production. Strawberry (Fragaria x ananassa) is among the most widely grown and consumed fruit species in the world, and it is also extremely sensitive to drought stress. We investigated the effect of mild drought stress (MDS) on phytochemical contents in the strawberry varieties (cv. Festival, Benicia and Monterey). We applied two irrigation regimes (control and MDS). A control irrigation regime was applied to the daughter plant for the first two weeks followed by applying fertigation at the end of the second week by allowing daily drainage fraction of 30%. In MDS regime, half of the water given in the control treatment was applied, and the drainage fraction was kept at around 15%. MDS resulted in an increased content of amino acids (Protein, l-alanin, l-Aspartic acid, l-methionin, l-Glutamic acid, Fenilalanin, Lizin, Histidin, Triozin, Glisin, Valin, Leucine, Threonine, Serin, Prolin and Arjinin) but just IsoLeucine rate was not increased. DS also showed increased contents of total phenolic and total anthocyanin but DPPH level decreased.

A roadmap for implementation of kV-CBCT online adaptive radiation therapy and initial first year experiences.

Online Adaptive Radiation Therapy (oART) follows a different treatment paradigm than conventional radiotherapy, and because of this, the resources, implementation, and workflows needed are unique. The purpose of this report is to outline our institution's experience establishing, organizing, and implementing an oART program using the Ethos therapy system. We include resources used, operational models utilized, program creation timelines, and our institutional experiences with the implementation and operation of an oART program. Additionally, we provide a detailed summary of our first year's clinical experience where we delivered over 1000 daily adaptive fractions. For all treatments, the different stages of online adaption, primary patient set-up, initial kV-CBCT acquisition, contouring review and edit of influencer structures, target review and edits, plan evaluation and selection, Mobius3D 2nd check and adaptive QA, 2nd kV-CBCT for positional verification, treatment delivery, and patient leaving the room, were analyzed. We retrospectively analyzed data from 97 patients treated from August 2021-August 2022. One thousand six hundred seventy seven individual fractions were treated and analyzed, 632(38%) were non-adaptive and 1045(62%) were adaptive. Seventy four of the 97 patients (76%) were treated with standard fractionation and 23 (24%) received stereotactic treatments. For the adaptive treatments, the generated adaptive plan was selected in 92% of treatments. On average(±std), adaptive sessions took 34.52±11.42min from start to finish. The entire adaptive process (from start of contour generation to verification CBCT), performed by the physicist (and physician on select days), was 19.84±8.21min. We present our institution's experience commissioning an oART program using the Ethos therapy system. It took us 12 months from project inception to the treatment of our first patient and 12 months to treat 1000 adaptive fractions. Retrospective analysis of delivered fractions showed that the average overall treatment time was approximately 35min and the average time for the adaptive component of treatment was approximately 20min.

COMPLETE RESPONSE AFTER HYPOFRACTIONATEDRADIOTHERAPY TREATMENT OF A RECURRENT CUTANEOUS SQUAMOUS CELL CARCINOMA OF THE AMPUTATED FINGER

Cutaneous squamous cell carcinoma is a relatively uncommon type of skin cancer that occurs most frequently on the hands. An 84-year-oldright-handedwomenpresented a recurrent cSCC of the 3rd finger four months following amputation and after declining adjuvant radiotherapy indicated given insufficient limits. Salvage hypofractionated Radiotherapy was performed with the 3D technique (60 Gy of RT in 20 fractions, at a daily dose fraction of 3 Gy over four weeks), with complete response and good aesthetic results.

Efficacy of Cryotherapy in Comparison to Standard Oral Care to Prevent Oral Mucositis during Concurrent Chemoradiotherapy in Head and Neck Cancer Patients

A quasi-experimental study was conducted at Radiation Oncology Department of National Institute of Cancer Research &amp; Hospital (NICRH), Dhaka, Bangladesh, between November 2020 and October 2021, to determine the efficacy of cryotherapy in comparison to standard oral care to prevent oral mucositis in head and neck cancer patients during receiving CCRT. A total 100 Patients (50 patients in each arm) were included in this study according to inclusion and exclusion criteria by purposive sampling technique. All patients in Arm A and Arm B received total 66 Gray in 33 daily fractions, 1 fraction per day, 5 fractions per week and inj. Cisplatin 40mg/m² was given intravenously 2/3 hours before radiotherapy on 1st day and then weekly. Arm A received cryotherapy and Arm B received standard oral care. Intervention started from the 1st day of CCRT up to the end of CCRT. WHO oral mucositis grading and visual analogue scale (VAS) were employed to determine the effects. All the information was recorded in a pre-tested semi-structured questionnaire. Total 100 patients (50 patients in each arm) were enrolled. Mean age of the patients of Arm A and Arm B was 55.28±7.82 and 55.92±8.33 respectively. Male and female ratio was 6.14:1 in two Arms. Other demographic profile, baseline characteristics were statistically not significant in both arms (P&gt;0.05). The grade-3 mucositis appeared after 5th week in Arm B and after 6th week in Arm A. The incidence of grade- 3 mucositis after 5th week during CCRT to 4 weeks after completion of therapy was 6% vs 0%, 14% vs 6%, 22% vs 10%, 14% vs 6%, 8% vs 2%, respectively for arm B and Arm A (P&lt;0.05). Total number of patients suffering from grade 3 mucositis was 6 (12%) and 12 (24%) for Arm A and Arm B respectively (p value was &lt;0.05). The mean duration of grade-3 or more mucositis between Arm A and Arm B was 2.04±1.78 and 10±1.72 days respectively (P&lt;0.05). The difference of median pain intensity between two arms was not statistically significant for 1st and 2nd week (P&gt;0.05). However, it was significant after 3rd week during CCRT to 4 weeks after completion of CCRT (P&lt;0.05). Cryotherapy during CCRT may be beneficial to prevent oral mucositis and pain than maintaining standard oral care.&#x0D; CBMJ 2023 January: vol. 12 no. 01 P: 03-11

Long-term outcomes and effects of hypofractionated radiotherapy in microinvasive breast cancer: Analysis from a randomized trial

PurposeThe natural history of microinvasive (T1mi) breast cancer is uncertain. The objective was to evaluate long-term local and distant recurrence rates following breast conserving surgery (BCS) in a prospective cohort of patients with T1mi compared to T1a-2 disease who received whole breast irradiation (WBI) in the context of a randomized trial of hypofractionation. Methods1234 patients with T1-2 N0 breast cancer were randomized to receive adjuvant WBI of 42.5Gy in 16 daily fractions, or 50Gy in 25 daily fractions after BCS. An analysis of patients with T1mi tumors compared with T1a-2 disease was performed. Kaplan-Meier estimates of local recurrence (LR), distant recurrence, and overall survival (OS) were compared using the log-rank test. ResultsMedian follow-up was 12 years. T1mi was found in 3% (n = 38) of patients. The 10-year LR rate was 22.6% in T1mi vs. 6.9% in T1a-2 breast cancer [hazard ratio (HR) = 3.73; 95% confidence interval (CI): 1.93, 7.19; p < 0.001]. The 10-year risk of distant recurrence was 5.1% for T1mi, and 12.1% for T1a-2 disease (HR = 0.56; 95% CI: 0.19, 1.84; p = 0.36). Ten-year OS was 91.5% in T1mi and 84.4% in T1a-2 disease, (HR = 0.48; 95% CI: 0.18, 1.30; p = 0.14). Rates of LR did not differ whether treated by hypofractionation or conventional fractionation (HR = 1.21; 95% CI: 0.35, 4.18; p = 0.77). ConclusionsThe risk of LR was considerably higher in patients with T1mi compared to T1a-2 tumors, but OS remained very good. Future research should evaluate the utility of wider local excision and boost radiation to optimize local control for microinvasive breast cancer.

Dosimetry comparison with helical tomotherapy, volumetric modulated arc therapy, and intensity-modulated radiotherapy for grade II gliomas: A single‑institution case series.

Radiotherapy is an essential postoperative treatment for grade II gliomas. However, comparative dosimetric studies of different radiotherapy plans for grade II gliomas are still lacking. Therefore, we conducted this case series analysis to compare the dosimetric differences among helical tomotherapy (TOMO), volumetric modulated arc therapy (VMAT), and intensity-modulated radiotherapy (IMRT) for grade II gliomas. To achieve that, seven diagnosed postoperative patients with grade II gliomas were analyzed by computed tomography and then planned with TOMO, VMAT, and IMRT. The plan target volume (PTV) prescribed dose was 50 Gy (daily fraction of 2.0 Gy, 5 days/week). The expected treatment efficiency was measured by monitor units (MUs) scoring. Treatment plans of the patients were compared in the quality of target volumes dosage coverage, the efficiency of dosage delivery, and the dosage exposure of normal adjacent organs at risk (OAR). Differences in each method were measured by utilizing the Nonparametric ANOVA. The study shows that TOMO achieved a significantly higher PTV-D98% (doses received by 98% of the PTV volume) than VMAT and IMRT (50.30 ± 0.13 vs 49.21 ± 0.19, p = 0.006; 50.30 ± 0.13 vs 49.78 ± 0.18, p = 0.014), while there was no difference in PTV-D2% (doses received by 2% of the PTV volume). IMRT achieved a conformity index (CI) preferably, and TOMO generated a favorable homogeneity index (HI) (p < 0.05 for both). The MUs were fewer for VMAT than IMRT and TOMO (294 ± 19, 572 ± 24, 317 ± 97, respectively). IMRT achieved better protection for the lens and brain stems. Our case series study indicated that TOMO, VMAT, and IMRT achieved a comparatively good target dosimetric coverage, and most OARs were protected well. IMRT is not inferior to TOMO and VMAT and is still very suitable for treating most grade II glioma patients.

Malignant Pleural Mesothelioma: Preliminary Toxicity Results of Adjuvant Radiotherapy Hypofractionation in a Prospective Trial (MESO-RT).

Malignant Pleural Mesothelioma (MPM) is a rare malignancy with an overall poor prognosis. The standard therapeutic strategy in early-stage disease is trimodality therapy. In this publication, we report the preliminary toxicity results of the first 20 patients treated with accelerated hypofractionated radiotherapy. Between July 2017 to June 2019, 20 MPM patients were enrolled and treated with accelerated hypofractionated radiotherapy using helical tomotherapy and intensity-modulated arc therapy. The prescription dose was 30 Gy in five daily fractions, while an inhomogeneous dose escalation to 40 Gy was prescribed based solely upon the presence of gross residual tumor. Only one case of G3 toxicity was reported, which was a bilateral pneumonitis that occurred two years after treatment probably due to superinfection. Median Time to Progression reached 18.2 months while one- and three-year Overall Survival rates were 85% (95% CI:60.4-94.9) and 49.5% (95% CI:26.5-68.9), respectively. Treatment of the intact lung with pleural intensity-modulated arc irradiation is a novel treatment strategy that appears to be safe, feasible, and without a high grade of lung toxicity. Survival rates and Time to Progression are encouraging.

Thoracic Radiation in Limited Stage Small Cell Lung Cancer: Trends in Radiation Fractionation

IntroductionThoracic radiotherapy (TRT) is standard of care for limited-stage small cell lung cancer (LS-SCLC). Although initial data supported the use of twice-daily (BID) radiation to a dose of 45 Gy, recent trials have suggested similar efficacy with daily fractionation (QD) to a dose of 60 to 70 Gy. This study evaluates trends in treatment regimen in patients treated with TRT for LS-SCLC. Materials and MethodsThe National Cancer Database (NCDB) was queried for patients with LS-SCLC treated with TRT between 2004 to 2017 grouped by RT fractionation QD vs. BID. Exclusion criteria were unknown stage, and unknown RT dose. Multivariable (MVA) analyses using logistic regression were performed to investigate factors associated with receipt of a specific fractionation schedule. ResultsA total of 17,453 patients met inclusion criteria, with 4,996 receiving BID treatment and 12,457 receiving QD treatment. The most common QD dose was 60 Gy (48.9%). Overall, QD fractionation has increased (1.3%/year). In 2004, 45 Gy BID treatment (41.4%) was the dominant fractionation. By 2017, 60 Gy QD (45.2%) increased (1.9%/y) to be the dominant fractionation, while 45 Gy BID (24.8%) decreased (-1.4%/y) to be the second most common fractionation. On MVA, factors that affect 1 treatment over the other were further stratified. ConclusionSince 2004, QD fractionation has been the preferred TRT regimen for patients with LS-SCLC compared to BID fractionation, with the proportion of patients getting QD treatment continuing to increase. The choice of treatment regimen appears to be influenced by both patient and facility characteristics.