Usefulness of C-11 methionine PET/CT for predicting recurrence, metastasis and prognosis of patients with lung cancer treated by carbon ion radiotherapy

Autor: Toubaru, Sachiko, Yoshikawa, Kyosan, Ohashi, Seiya, Hasebe, Mitsuhiko, Ishikawa, Hiroyuki, Sagou, Kenji, Tamura, Katsumi, Tanimoto, Katsuyuki, Kandatsu, Susumu, Baba, Masayuki, Fukumura, Toshimitsu, Saga, Tsuneo, Kawaguchi, Koji, Tsujii, Hirohiko
Jazyk: angličtina
Rok vydání: 2009
Popis: The carbon ion radiotherapy (CIRT) has been introduced in our institute, and we have treated lung cancer using carbon ion beam. We performed C-11 methionine (MET) PET/CT and compared the difference of MET uptake level before and after CIRT among lung cancers. We evaluated whether MET uptake and its change after CIRT were early predictor for recurrence, systemic metastasis or survival factors in patients with lung cancer. Methods: MET-PET/CT was performed in 56 patients with lung cancer before and after CIRT. There were 26 squamous cell carcinoma, 31 adenocarcinoma and 1 large cell neuroendocrine carcinoma (2 patients had double cancers with squamous cell carcinoma and adenocarcinoma). The average patient age was 74.6 years (range 40 to 89). Patients were followed for 5.4 to 58.5 months (mean: 23.1 months) after CIRT. PET with 2-raw MDCT, Biograph Duo, was used for PET/CT imaging. PET/CT was performed before and after CIRT for each patient. Post therapeutic PET/CT were done at 1 month (23 cases) or 3 months (33 cases) after CIRT completion. Tumor MET uptake was measured with a semi-quantitative index, tumor to normal tissue ratio (TNR). The tumor TNR, its change after CIRT, result of recurrence, result of systemic metastasis and result of prognosis were entered into Kaplan-Meire analysis. Results: We examined the relationship between TNRs (TNR before CIRT, TNR after CIRT, change of TNR by CIRT) and clinical factors (recurrence, metastasis, prognosis). Nine relations between them were analyzed by Kaplan-Meire analysis. There were statistically significant relations between baseline TNR and recurrence, baseline TNR and prognosis, TNR at 3 months after CIRT and prognosis. Patients with high TNR before CIRT had a significant higher recurrence rate and poorer prognosis than patients with low TNR (Cutoff 4.0 and 4.4, p=0.001 and 0.023, respectively). Patient with high TNR at 3 months after CIRT had a significant poorer prognosis than patients with low TNR (Cutoff 3.0, p=0.038). TNR at 1 month after CIRT didn`t show any statistically significant relation to recurrence, metastasis or prognosis. There was no significant relation between any TNRs and incidence of metastasis. Conclusions: MET uptake in lung cancer was a successful predictor of recurrence and survival. TNR at 3 months after CIRT is better predictor for prognosis than TNR at 1 month after CIRT.
The 2009 EANM Congress
Databáze: OpenAIRE
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