{"id":166833,"date":"2021-01-30T12:06:57","date_gmt":"2021-01-30T09:06:57","guid":{"rendered":"https:\/\/en.buradabiliyorum.com\/radiation-oncology-trials-using-pet-with-fdg-uptake-among-nsclc-patients\/"},"modified":"2021-01-30T12:06:57","modified_gmt":"2021-01-30T09:06:57","slug":"radiation-oncology-trials-using-pet-with-fdg-uptake-among-nsclc-patients","status":"publish","type":"post","link":"https:\/\/buradabiliyorum.com\/en\/radiation-oncology-trials-using-pet-with-fdg-uptake-among-nsclc-patients\/","title":{"rendered":"#Radiation Oncology trials using PET with FDG uptake among NSCLC patients"},"content":{"rendered":"

“#Radiation Oncology trials using PET with FDG uptake among NSCLC patients<\/strong>”<\/p>\n

\n Two radiation oncology trials presented at the IALSC World Conference on Lung Cancer Singapore highlight how some researchers are exploring use of higher radiation boost doses to only PET-positive regions in locally-advanced non-small cell lung cancer (NSCLC). A previous large RTOG phase III trial revealed that the unform delivery of a high dose to the entire tumor led to poorer survival.\n <\/p>\n

In one study, Prof. Feng-Ming (Spring) Kong, Case Western Reserve University School of Medicine, in Cleveland, Ohio presented the results of a multicenter trial which aimed to determine whether adaptive isotoxic radiation dose escalation to mid-treatment FDG-PET provides superior local tumor control compared to a standard uniform dose of 60 Gy in patients with stage III NSCLC.<\/p>\n

Prof. Kong and the research centers involved in the trials enrolled 138 patients with stage III NSCLC who were medically fit for concurrent chemoradiation. The patients were randomly assigned by a 1:2 ratio to standard (60 Gy) arm or to an adaptive-therapy arm, with dose individualized to 20 Gy mean lung dose (MLD), and adapted to residual tumor on the mid-treatment FDG-PET\/CT. All patients had FDG-PET performed around 40 Gy mid-treatment, and radiation therapy was delivered in 30 daily fractions (Fx).<\/p>\n

Of 138 patients enrolled between February 2012 and March 2017, 127 were eligible and analyzable, with 43 and 84 patients in the standard and adaptive arms, respectively, with a minimum follow-up of 3.7 and 3.4 years for surviving patients, also respectively.<\/p>\n

The adaptive arm consisted of an initial plan of 2.2 Gy\/Fx for 21 Fx followed by an adaptive radiation therapy boost to mid-treatment FDG-PET target using a variable prescript<\/a>ion of 2.2-3.8 Gy\/Fx for the final 9 Fx. The primary endpoint of this report was 2-year local-regional tumor progression free (LRPF), with inclusion of overall and in-field LRPF, assessed independently and blindly by radiologists.<\/p>\n

There were no significant differences in lung, esophagus, and heart toxicities, though the adaptive arm had numerically higher mean doses of these organs at risk. The 2-year overall LRPF rates were 59.5% (95% CI: 37.9, 75.7) on the standard arm, and 54.6% (95% CI: 39.9, 67.0) on the adaptive arm. The media<\/a>n LRPF time was 27.5 months (95% CI: 14.3, not reached) on the standard arm and 28.4 months (95% CI: 19.1, not reached) on the adaptive arm. There were no significant differences in overall survival, progression-free survival, or lung cancer-specific survival between the two arms, according to the presentation by Dr. Kong.
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“This is the first randomized trial that demonstrated the feasibility and safety of performing biologically adaptive radiation therapy escalation in a multicenter setting in patients with stage III NSCLC. This preliminary analysis did not show an improvement in overall local regional tumor control,” Dr. Kong reported.<\/p>\n

In the second study, Dr. Saskia Cooke, The Netherlands Cancer Institute in Amsterdam, Netherlands, reports on local and regional failure in the phase II PET-Boost trial (NCT01024829). In this study, patients with stage II-III non-small cell lung cancer (NSCLC) were treated with hypofractionated dose escalation to either the primary tumor as a whole (Arm A) or the high fluorodeoxyglucose (FDG)-uptake region inside the PT (> 50% SUVmax; Arm B).<\/p>\n

The trial randomly assigned 107 patients\u201482% had stage III disease and most patients (72%) received concurrent chemoradiotherapy. In Arms A and B, median gross tumor volume (GTV) for the primary tumor was 100 and 115 cm3<\/sup>, respectively; median GTV for the involved lymph nodes was 18 and 20 cm3<\/sup>, respectively. Median fraction dose was 3.25 Gy to planning target volume (PTV) to the entire primary tumor and 3.50 Gy to PTV 50% SUVmax, resulting in total planned physical dose of 78.0 and 84.0 Gy, in 24 fractions. Median overall treatment time was 34 days in both arms, and median follow-up for CT scans in central review was 12.6 months.<\/p>\n

In a previous report, the authors revealed that the primary tumor was non-measurable on follow-up in 27% of patients [Cooke S, 2020]. Of the 12 patients in Arm A who experienced locoregional failure, 2 had local failure (LF) without regional failure (RF) and 9 had RF without LF. Of the 15 patients in Arm B, 4 had LF without RF and 10 had RF without LF. In Arms A and B, respectively, the 2-year cumulative incidence of LF was 11% and 18%, and 28% and 25% for RF. The authors concluded that “dose escalation to the whole PT or 50% SUVmax in patients with NSCLC led to excellent local control rates in both treatment arms”. However, few patients were evaluable for assessment of local failure at 2-years, grade 5 toxicity rates was previously reported to be 16% [van Diessen J, 2018], with 3-year OS rates of only 37% in armA and 33% in armB, respectively.\n <\/p>\n\n

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Study shows safety of adaptive radiotherapy in non small cell lung cancer patients\n <\/p><\/div>\n

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\n Provided by
\n International Association for the Study of Lung Cancer<\/p>\n

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Citation<\/strong>:
\n Radiation Oncology trials using PET with FDG uptake among NSCLC patients (2021, January 30)
\n retrieved 30 January 2021
\n from https:\/\/medicalxpress.com\/news<\/a>\/2021-01-oncology-trials-pet-fdg-uptake.html<\/p>\n

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