MATERIALS/METHODS: From June 2008 through June 2011, 210 patients with HNC receiving RT were randomised to either a control arm or humidification using the Fisher & Paykel Healthcare MR880 humidifier. This subset analysis involves patients recruited from Auckland City Hospital treated with a prescribed dose of ≥70 Gy. Regression models included control variables for Planning Target Volume 70 GY (PTV70Gy); Equivalent Uniform Dose (EUD) MOIST and TSV (surrogates of total mucosal and total swallowing volumes respectively).
RESULTS: The analysis included 39 patients (humidification 20, control 19). There was a significant odds reduction in CTCAE v3.0 functional mucositis score of 0.29 associated with the use of humidification (p
SUMMARY: Immunotherapy has less effect on the patient bone marrow compared to chemotherapy. The potential synergy between radiotherapy and immunotherapy may improve local control and survival for older patients with selected cancer. Preliminary data are encouraging because of better survival and local control in diseases which are traditionally resistant to radiotherapy and chemotherapy such as melanoma and renal cell carcinoma. Key Message: We propose a new paradigm combining immunotherapy at a reduced dose and/or extended dosing intervals and hypofractionated radiotherapy for older patients with selected cancer which needs to be tested in future clinical trials.
METHODS: We conducted a population-based study using data from the Global Cancer Observatory (GLOBOCAN) 2022 and predicted global radiotherapy demands and workforce requirements in 2050. We obtained incidence figures for 29 types of cancer across 183 countries and derived the cancer-specific radiotherapy use rate using the 2013 Collaboration for Cancer Outcomes Research and Evaluation model. We delineated the proportion of people with cancer who require radiotherapy and can be accommodated within the existing installed capacity, assuming an optimal use rate of 50% or 64%, in both 2022 and 2050. A use rate of 50% corresponds to the global average and a use rate of 64% considers potential re-treatment scenarios, as indicated by the 2013 Collaboration for Cancer Outcomes Research and Evaluation (CCORE) radiotherapy use rate model. We established specified requirements for teletherapy units at a ratio of 1:450 patients, for radiation oncologists at a ratio of 1:250 patients, for medical physicists at a ratio of 1:450 patients, and for radiation therapists at a ratio of 1:150 patients in all countries and consistently using these ratios. We collected current country-level data on the radiotherapy-professional workforce from national health reports, oncology societies, or other authorities from 32 countries.
FINDINGS: In 2022, there were an estimated 20·0 million new cancer diagnoses, with approximately 10·0 million new patients needing radiotherapy at an estimated use rate of 50% and 12·8 million at an estimated use rate of 64%. In 2050, GLOBOCAN 2022 data indicated 33·1 million new cancer diagnoses, with 16·5 million new patients needing radiotherapy at an estimated use rate of 50% and 21·2 million at an estimated use rate of 64%. These findings indicate an absolute increase of 8·4 million individuals requiring radiotherapy from 2022 to 2050 at an estimated use rate of 64%; at an estimated use rate of 50%, the absolute increase would be 6·5 million individuals. Asia was estimated to have the highest radiotherapy demand in 2050 (11 119 478 [52·6%] of 21 161 603 people with cancer), followed by Europe (3 564 316 [16·8%]), North America (2 546 826 [12·0%]), Latin America and the Caribbean (1 837 608 [8·7%]), Africa (1 799 348 [8·5%]), and Oceania (294 026 [1·4%]). We estimated that the global radiotherapy workforce in 2022 needed 51 111 radiation oncologists, 28 395 medical physicists, and 85 184 radiation therapists and 84 646 radiation oncologists, 47 026 medical physicists, and 141 077 radiation therapists in 2050. We estimated that the largest proportion of the radiotherapy workforce in 2050 would be in upper-middle-income countries (101 912 [38·8%] of 262 624 global radiotherapy professionals).
INTERPRETATION: Urgent strategies are required to empower the global health-care workforce and facilitate the fundamental human right of access to suitable health care. A collective effort with innovative and cost-contained health-care strategies from all stakeholders is warranted to enhance global accessibility to radiotherapy and address challenges in cancer care.
FUNDING: China Medical Board Global Health Leadership Development Program, Shanghai Science and Technology Committee Fund, China Ministry of Science and Technology Department of International Cooperation High Level Cooperation and Exchange Projects, and Fudan University Office of Global Partnerships Key Projects Development Fund.
TRANSLATIONS: For the Arabic, Chinese, French, Russian and Spanish translations of the summary see Supplementary Materials section.
MATERIALS AND METHODS: Between March 2011 and May 2012, 20 patients were treated with 55 fractions of brachytherapy using tandem and ovoids and underwent post-implant CT scans. The external beam radiotherapy (EBRT) dose was 48.6 Gy in 27 fractions. HDR brachytherapy was delivered to a dose of 21 Gy in three fractions. The ICRU bladder and rectum point doses along with 4 additional rectal points were recorded. The maximum dose (DMax) to rectum was the highest recorded dose at one of these five points. Using the HDR plus 2.6 brachytherapy treatment planning system, the bladder and rectum were retrospectively contoured on the 55 CT datasets. The DVHs for rectum and bladder were calculated and the minimum doses to the highest irradiated 2cc area of rectum and bladder were recorded (D2cc) for all individual fractions. The mean D2cc of rectum was compared to the means of ICRU rectal point and rectal DMax using the Student's t-test. The mean D2cc of bladder was compared with the mean ICRU bladder point using the same statistical test .The total dose, combining EBRT and HDR brachytherapy, were biologically normalized to the conventional 2 Gy/fraction using the linear-quadratic model. (α/β value of 10 Gy for target, 3 Gy for organs at risk).
RESULTS: The total prescribed dose was 77.5 Gy α/β10. The mean dose to the rectum was 4.58 ± 1.22 Gy for D 2cc, 3.76 ± 0.65 Gy at D ICRU and 4.75 ± 1.01 Gy at DMax. The mean rectal D 2cc dose differed significantly from the mean dose calculated at the ICRU reference point (p<0.005); the mean difference was 0.82 Gy (0.48 -1.19 Gy). The mean EQD2 was 68.52 ± 7.24 Gy α/β3 for D 2cc, 61.71 ± 2.77 Gy α/β3 at D ICRU and 69.24 ± 6.02 Gy α/β3 at DMax. The mean ratio of D 2cc rectum to D ICRU rectum was 1.25 and the mean ratio of D 2cc rectum to DMax rectum was 0.98 for all individual fractions. The mean dose to the bladder was 6.00 ± 1.90 Gy for D 2cc and 5.10 ± 2.03 Gy at D ICRU. However, the mean D 2cc dose did not differ significantly from the mean dose calculated at the ICRU reference point (p=0.307); the mean difference was 0.90 Gy (0.49-1.25 Gy). The mean EQD2 was 81.85 ± 13.03 Gy α/β3 for D 2cc and 74.11 ± 19.39 Gy α/β3 at D ICRU. The mean ratio of D 2cc bladder to D ICRU bladder was 1.24. In the majority of applications, the maximum dose point was not the ICRU point. On average, the rectum received 77% and bladder received 92% of the prescribed dose.
CONCLUSIONS: OARs doses assessed by DVH criteria were higher than ICRU point doses. Our data suggest that the estimated dose to the ICRU bladder point may be a reasonable surrogate for the D 2cc and rectal DMax for D 2cc. However, the dose to the ICRU rectal point does not appear to be a reasonable surrogate for the D 2cc.