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Yoshiki Takada

Publications and source records attributed to Yoshiki Takada.

4 recordsLinked to original sources
PubMed2003

Predictive value of dose-volume histogram parameters for predicting radiation pneumonitis after concurrent chemoradiation for lung cancer.

PURPOSE: To clarify whether the percentage of pulmonary volume irradiated to >20 Gy (V20) is related to the incidence and grade of radiation pneumonitis (RP) in cases of lung cancer treated with concurrent chemoradiation. METHODS AND MATERIALS: The subjects comprised 71 patients with lung cancer who were treated with conventionally fractionated definitive concurrent chemoradiation. The chemotherapy agents were carboplatin or cisplatin combined with taxane for most patients. Radiotherapy was delivered at 1.8-2.0 Gy fractions once daily to a total of 48-66 Gy (median 60). We analyzed the relation between RP grade and V20. Univariate and multivariate analyses were performed to assess patient- and treatment-related factors, including age, gender, smoking history, pulmonary function (forced expiratory volume in 1 s), tumor location (upper lobe vs. middle/lower lobe), chemotherapy regimen (platinum + taxane vs. other), total dose, overall radiation periods in addition to V20. RESULTS: With a median follow-up of 7.5 months, an RP grade of 0, 1, 2, 3, and 5 was observed in 16, 35, 17, 1, and 2 patients, respectively; the corresponding mean V20 values were 20.1%, 22.0%, 26.3%, 27.0%, and 34.5%. The 6-month cumulative incidence of RP greater than Grade 2 was 8.7%, 18.3%, 51%, and 85% in patients with a V20 of or=31%, respectively (p <0.0001). According to both univariate and multivariate analyses, V20 was the only factor associated with RP of Grade 2 or greater. CONCLUSION: The incidence and grade of RP are significantly related to the V20 value. Thus, V20 appears to be a factor that can be used to predict RP after concurrent chemoradiation for lung cancer.

Adult↗
PubMed2003

[Diagnostic imaging--recent progress].

Current advances in the diagnostic imaging for lung cancer includes multidetector-row CT (MDCT), lung cancer screening using low-dose MDCT and fluorodeoxyglucose positron emission tomography (FDG-PET) imaging. There is no question about the clinical usefulness of MDCT, and the further development of the hardware and the software of MDCT will open new horizons for CT diagnosis. PET is not an alternative modality to CT but a supplementary one, which adds metabolic information to the morphology. Recently, experimental research on the refraction imaging of human lung specimens has been performed with synchrotron radiation. With progressive refinement, this technique may come to have some practical purpose in diagnosing lung cancer in vivo.

Carcinoma, Squamous Cell↗
PubMed2002

Subcutaneous fibrosis after whole neck irradiation.

PURPOSE: To identify the risk factors for moderate to severe subcutaneous fibrosis after whole neck irradiation. MATERIALS AND METHODS: We analyzed 233 cases of patients who had undergone whole neck irradiation with 4-MV X-ray or 8-10-MeV electrons, or both, and had been followed with regard to their skin condition for at least 1 year. The prescribed dose to the whole neck ranged from 19.2 to 72.4 Gy (median 50). The skin-absorbed dose was specified as that at a depth of 4.1 mm (d4.1-mm(depth)), and a biologically equivalent dose (BED) of d4.1-mm(depth) was also estimated (BED(1.8) 4.1-mm(depth)). RESULTS: Univariate analysis revealed that previous neck dissection, concurrent chemotherapy, corticosteroid administration as a part of chemotherapy, fractionation, and BED(1.8) 4.1-mm(depth) were significant prognostic variables. Multivariate analysis showed that BED(1.8) 4.1-mm(depth) and previous neck dissection were the only prognostic variables for moderate to severe subcutaneous fibrosis. CONCLUSION: A high dose to a 4.1-mm depth of the skin and a history of neck dissection were identified as the predominant risk factors for moderate to severe subcutaneous fibrosis after whole neck irradiation. A subcutaneous dose should be considered in radiotherapy treatment planning involving the whole neck, especially in cases in which patients have undergone previous neck dissection.

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