Preliminary results of a phase III trial of spontaneous animal tumors to heat and/or radiation: early normal tissue response and tumor volume influence on initial response

Dewhirst, Mark W.; Connor, William; Sim, Dalice

doi:10.1016/0360-3016(82)90455-2

Cited by 50 publications

(12 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, the estimated local control distribution showed that the duration of response was less affected by tumour volume in the combined modality than in the radiation alone arm. These results are in agreement with those obtained in a prospective randomized trial on spontaneous animal tumours (Dewhirst et al 1982 in that the addition of heat was more damaging to the large than to the small tumours, although the prescribed tumour temperature was more easily achieved in small than in large tumours ( figure 6). In other words, it is easier to heat small lesions to a prescribed temperature than large lesions; however, in lesions in which the prescribed temperature was achieved for a given time, the advantage of combined over single treatment modality was greater in large than in small tumours.…”

Section: Discussionsupporting

confidence: 93%

Tumour response to heat and radiation: Prognostic variables in the treatment of neck node metastases from head and neck cancer

Arcangeli¹,

Arcangeli²,

Guerra³

et al. 1985

International Journal of Hyperthermia

View full text Add to dashboard Cite

A total of 38 patients with 81 multiple neck node metastases from squamous cell carcinoma of head and neck were treated with radiotherapy alone or with radiotherapy plus hyperthermia. Irradiation was delivered following a three fractions per day schedule of 2 + 1.5 + 1.5 Gy/day, with 4 h intervals between fractions, up to a total dose of 60 Gy. Heat was applied by means of a 500 MHz apparatus. Temperature data were converted to equivalent minutes at 42.5 degrees (Eq 42.5). Initial complete response rates and local control distribution were compared for subgroups of tumour volume and thermal dose. The data indicated that the volume effect was less pronounced in the combined modality than in the radiation alone arm, suggesting that the addition of heat was more damaging to the large than to the small lesions. A striking thermal dose-response relationship was shown, although complete response rates increased only after a certain thermal dose was accumulated, clearly indicating the presence of a threshold dose.

show abstract

Section: Discussionsupporting

confidence: 93%

Tumour response to heat and radiation: Prognostic variables in the treatment of neck node metastases from head and neck cancer

Arcangeli¹,

Arcangeli²,

Guerra³

et al. 1985

International Journal of Hyperthermia

View full text Add to dashboard Cite

show abstract

“…Indeed, RT has become an essential part of cancer treatment in animals 23,67 ; the advances in high-precision treatment delivery and multimodal imaging used for human patients are increasingly being translated to veterinary practice, thereby providing opportunities to use domesticated animals with spontaneously arising tumors to explore the potential benefits of FLASH RT. 23,67 Radiation effects have been well studied in cats and dogs [68][69][70] ; these animals could serve as models for testing the safety of FLASH RT. 23 As one example, a phase III randomized trial of FLASH RT versus CONV RT for cats with squamous cell carcinoma of the nasal planum is currently ongoing at the CHUV (Lausanne University 71 Unfortunately, these trials do not include a control condition in which RT is given at CONV dose rates.…”

Section: Path To Clinical Translation: Models Relevant To Clinical Qu...mentioning

confidence: 99%

Ultra‐high dose rate electron beams and the FLASH effect: From preclinical evidence to a new radiotherapy paradigm

et al. 2022

View full text Add to dashboard Cite

In their seminal paper from 2014, Fauvadon et al. coined the term FLASH irradiation to describe ultra-high-dose rate irradiation with dose rates greater than 40 Gy/s, which results in delivery times of fractions of a second. The experiments presented in that paper were performed with a high-dose-per-pulse 4.5 MeV electron beam, and the results served as the basis for the modern-day field of FLASH radiation therapy (RT). In this article, we review the studies that have been published after those early experiments, demonstrating the robust effects of FLASH RT on normal tissue sparing in preclinical models. We also outline the various irradiation parameters that have been used. Although the robustness of the biological response has been established, the mechanisms behind the FLASH effect are currently under investigation in a number of laboratories. However, differences in the magnitude of the FLASH effect between experiments in different labs have been reported. Reasons for these differences even within the same animal model are currently unknown, but likely has to do with the marked differences in irradiation parameter settings used. Here, we show that these parameters are often not reported, which complicates large multistudy comparisons. For this reason, we propose a new standard for beam parameter reporting and discuss a systematic path to the clinical translation of FLASH RT.

show abstract

“…If the nodes were not involved, they were irradiated prophylactically. Details of the radiotherapy techniques have been provided elsewhere (Dewhirst et al 1982). …”

Section: Radiotherapymentioning

confidence: 99%

Local control and distant metastases in primary canine malignant melanomas treated with hyperthermia and/or radiotherapy

Dewhirst

Sim

Forsyth

et al. 1985

International Journal of Hyperthermia

Self Cite

View full text Add to dashboard Cite

Forty-three dogs with primary malignant melanoma were randomized to receive radiotherapy alone (XRT) or hyperthermia plus radiotherapy (delta + XRT). Tumour responses were analysed in terms of complete response rates, rate of one year disease free survival and the incidence and time to develop distant metastasis. The frequency of complete responses (CR) was greater with adjuvant heat (76 per cent vs 21 per cent for XRT; P = 0.001). A trend towards an improvement in one year disease free survival was observed with delta + XRT (23.8 per cent) as compared with XRT (7.7 per cent), but the difference was not statistically significant. The frequency of distant metastases was not different between the two treatments. Descriptors of intratumoural temperatures achieved during therapy indicated that higher CR rates could be achieved with higher minima. When minima were less than and greater than 20 Equivalent minutes at 43 degrees C (Eq43) the CR rates were 64 and 90 per cent, respectively. One year disease free survival rates and frequencies of distant metastases seemed to be correlated with the intratumoural temperatures as well. This was reflected in analyses examining temperature minima and maxima. Examination of patterns of failure suggested that the most plausible explanation for the correlation between intratumoural temperature and metastases was the high local failure rate (70 per in the heated group). The results of this study emphasize the need for further investigation of the influence of local hyperthermia as a part of curative therapy on the frequency of distant metastases.

show abstract

Preliminary results of a phase III trial of spontaneous animal tumors to heat and/or radiation: early normal tissue response and tumor volume influence on initial response

Cited by 50 publications

References 27 publications

Tumour response to heat and radiation: Prognostic variables in the treatment of neck node metastases from head and neck cancer

Tumour response to heat and radiation: Prognostic variables in the treatment of neck node metastases from head and neck cancer

Ultra‐high dose rate electron beams and the FLASH effect: From preclinical evidence to a new radiotherapy paradigm

Local control and distant metastases in primary canine malignant melanomas treated with hyperthermia and/or radiotherapy

Contact Info

Product

Resources

About