楯谷 一郎

BACKGROUND: Precision oncology leverages the molecular and genetic characteristics of tumors to enable accurate diagnosis and effective treatment selection. However, recent clinical trials have highlighted the limitations of current approaches and underscored the need to integrate static molecular profiling with functional analyses using patient-derived xenograft (PDX) models-particularly for cancers such as head and neck cancer (HNC), where driver mutations are rare and prognosis remains poor. METHODS: Here, we aimed to establish a large-scale PDX library for HNC, termed the Fujita Xenograft Library (FXeL), annotated with detailed clinical information. Since 2022, tumor specimens from over 100 surgical cases at Fujita Health University Hospital have been transplanted into immunodeficient mice, resulting in the successful establishment of 62 PDX models. RESULTS: Advanced clinical stage was significantly associated with successful engraftment, and serial passaging led to progressively accelerated tumor growth. Comparative analyses of genomic profiles between patient tumors and PDXs demonstrated that major cancer-related mutations were largely preserved in PDXs, while clonal selection and evolution occurred during engraftment. Histopathological features, including keratinization and nuclear atypia, were retained, whereas stromal components such as cancer-associated fibroblasts exhibited compositional shifts. Furthermore, drug sensitivity assays revealed that PDX responses to cisplatin (CDDP) closely mirrored the clinical outcomes of the corresponding patients. CONCLUSIONS: The FXeL represents a robust and scalable platform for investigating HNC biology and therapeutic response. Despite limitations such as stromal remodeling and the absence of an immune microenvironment, these models provide valuable translational insights and support the advancement of functional precision oncology.

OBJECTIVES: As the global population ages, age-related vocal fold atrophy (ARVA) is increasingly recognized. However, no nationwide epidemiological studies have been conducted. We aimed to investigate the clinical characteristics and treatments of ARVA in Japan, the world's most aged society. METHODS: This multicenter retrospective study, part of the Tokyo Voice Center Initiative, analyzed medical records of 1365 patients diagnosed with ARVA between 2018 and 2022. The primary survey examined the involvement of speech language pathologist (SLP) and the routine use of stroboscopic examinations at 34 certified institutions. The secondary survey assessed hoarseness severity (via maximum phonation time and voice handicap index-10), age of onset, treatment methods, and treatment outcomes at 14 certified institutions. RESULTS: All diagnoses and assessments were conducted by departments of otolaryngology-head and neck surgery. Of the 1365 patients (637 females, 728 males; mean age: 64.6 ± 14.7 years), 1097 received treatment and 268 did not. Treatments included voice therapy (n = 1031), injection augmentation (n = 162), and surgery (n = 18), with some receiving multiple therapies. Voice therapy was more effective when provided by voice-specialized SLPs. Invasive treatments yielded greater voice improvement overall. Significant differences in age and sex ratios were found between institutions (P < 0.01). CONCLUSION: These findings underscore the need for cross-specialty education, broader awareness of ARVA, and establishment of a national database and severity classification system.

OBJECTIVE: To evaluate the safety and feasibility of transaxillary robotic thyroidectomy (TART) in Japan by comparing early cases with video-assisted neck surgery (VANS). METHODS: Single-center retrospective review of 31 consecutive thyroid lobectomies: 16 VANS (Nov 2020-Feb 2025) and 15 TART (Mar 2022-Feb 2025). TART used da Vinci Surgical system (da Vinci) Xi for early cases and predominantly da Vinci SP thereafter. Indications included differentiated cancer ≤4 cm, cN0, unilateral disease without extrathyroidal invasion, or follicular tumors 3-5 cm. Operative time, blood loss, hospital stay, complications, and cosmetic outcomes were evaluated and compared with statistical analysis. RESULTS: All procedures were completed without conversion to open surgery. Blood loss (16.5 g vs 25.8 g) and length of stay (6.3 vs 6.1 days) were comparable. Complications included two transient recurrent laryngeal nerve palsies after VANS and, after TART, one axillary bleed controlled under local anesthesia and one lymphatic leak; overall rates were similar. High cosmetic satisfaction was reported in both cohorts. CONCLUSION: Early experience shows TART is feasible and safe in Japan, achieving perioperative outcomes comparable to VANS with excellent cosmetic results.