Takeo Hara

Background & Aims: . We investigated the feasibility and the utility of patient-derived 3D organoids of esophageal and oropharyngeal squamous cell carcinomas. Methods: . Results: = 0.0357, progressive and stable diseases, n = 10 vs. partial response, n = 6). The 3D organoid formation capability and 5-fluorouracil resistance were accounted for by cancer cells with high CD44 expression and autophagy, respectively. Such cancer cells were found to be enriched in patient-derived 3D organoids surviving 5-fluorouracil treatment. Conclusions: The single cell-based 3D organoid system may serve as a highly efficient platform to explore cancer therapeutics and therapy resistance mechanisms in conjunction with morphological and functional assays with implications for translation in personalized medicine.

UNLABELLED: 11C-choline and FDG are PET tracers used to visualize various malignancies. In this study, we compared their capabilities in detecting mediastinal lymph node metastasis originating from non-small cell lung cancer (NSCLC). METHODS: Twenty-nine patients with biopsy-proven NSCLC were studied with PET. 11C-choline PET and FDG PET were performed from 5 and 40 min, respectively, after injection of 370 MBq tracer. PET data were analyzed in terms of the standardized uptake value (SUV). After the PET study, the patients underwent lung resection and mediastinal lymph node dissection. The resected specimens were examined pathologically, and the PET data were analyzed in reference to the pathologic data. RESULTS: With 11C-choline, the SUV in metastasis was similar to the SUV in the primary tumor, where the similarity of the SUV was 100% allowing for a 40% difference. With FDG, small metastases were invisible on the PET image. The SUV of FDG in metastasis was much smaller than that in the primary tumor, and the similarity of the SUV was only 19% allowing for a 40% difference. When pathologic findings were used as standards, the sensitivities of 11C-choline PET and FDG PET in detecting mediastinal lymph node metastasis were 100% and 75%, respectively. CONCLUSION: 11C-choline PET was very effective in detecting lymph node metastases in the mediastinum originating from NSCLC, with a sensitivity of 100%. 11C-choline PET promises to be useful not only before surgery but also after surgery.

PURPOSE: To evaluate the effectiveness of positron emission tomography (PET) with carbon-11 choline in brain tumor imaging. MATERIALS AND METHODS: A rat glioma cell line (C6) was incubated with C-14 choline; the time course of uptake and metabolism was determined in vitro. C-11 choline was injected intravenously in tumor-bearing rats; the time course of distribution in organs was determined. C-11 choline also was injected intravenously in 20 patients (aged 6-86 years) with brain tumors and two volunteers (aged 38 and 58 years); distribution of the tracer in the brain was determined. Regional cerebral blood flow was measured by using oxygen-15 water on the same day. RESULTS: C-14 choline was metabolized to phosphoryl choline in glioma cells. The uptake of C-11 choline by glioblastoma cells was three to four times higher than that in the rat brain. All brain tumors took up more C-11 choline than did normal brain; thus, brain tumors that were not treated, as well as those that were treated with surgery or radiation therapy, were depicted. The tumor-normal brain uptake ratio of C-11 choline in brain tumor did not correlate with the O-15 water regional blood flow in the corresponding area. CONCLUSION: C-11 choline PET can depict brain tumors effectively. This method was clinically useful in patients who had undergone surgery.