Clinical utility of thoracoscopy in elderly tuberculous pleurisy patients under local anesthesia.

INTRODUCTION: Diagnosing tuberculous pleurisy is important in Japan because it currently has a moderate tuberculosis prevalence. However, physicians often have difficulty making a diagnosis. It was reported that thoracoscopy under local anesthesia is useful for the diagnosis of tuberculous pleurisy, but there are no reports focusing on elderly patients. METHODS: In this study, the usefulness of thoracoscopy under local anesthesia was evaluated in elderly patients. Among 170 patients who underwent thoracoscopy under local anesthesia at our hospital during 11 years from January 2008 to December 2018, those aged 75 years or older (n = 75) were investigated retrospectively. RESULTS: A total of 55 patients underwent thoracoscopy under local anesthesia for detailed examination of pleural effusion of unknown cause. Of these, 18 were diagnosed as tuberculous pleurisy. The median age was 82 years (range: 75-92 years). The diagnosis of tuberculous pleurisy was made in 11 patients in whom Mycobacterium tuberculosis was detected and in four patients whose pathological findings indicated epithelioid granuloma accompanied by caseous necrosis. Clinical diagnosis was made in the remaining three patients based on thoracoscopic findings of the pleural cavity and a high level of adenosine deaminase in pleural fluid. No serious complications attributable to the examination were observed in any patient. CONCLUSIONS: Thoracoscopy under local anesthesia was useful for the diagnosis of tuberculous pleurisy in elderly patients, with useful information being also obtained for the treatment of tuberculosis.

A Novel Theranostic Combination of Near-infrared Fluorescence Imaging and Laser Irradiation Targeting c-KIT for Gastrointestinal Stromal Tumors.

It is difficult to distinguish gastrointestinal stromal tumors (GISTs) from other types of submucosal tumors under conventional gastrointestinal endoscopy. We aimed to detect GISTs by molecular fluorescence imaging using a near-infrared (NIR) photosensitizer (IR700)-conjugated anti-c-KIT antibody and to treat GISTs by photoimmunotherapy with NIR irradiation as a non-invasive theranostic procedure. We also investigated the therapeutic mechanisms. Methods: Human GIST cell lines GIST-T1 and GIST-882M were incubated with IR700-conjugated anti-c-KIT antibody, IR700-12A8, and observed by confocal laser microscopy. Mice with GIST-T1 xenografts or rats with orthotopic xenografts were injected with IR700-12A8 or AF488-conjugated antibody, and observed under IVIS or autofluorescence imaging (AFI) endoscopy. GIST cells were treated with IR700-12A8 and NIR light in vitro and vivo, and cell viability, histology and apoptosis were evaluated. Results: Strong red fluorescence of IR700-12A8 was observed on the cell membrane of GIST cells and was gradually internalized into the cytoplasm. Tumor-specific accumulation of IR700-12A8 was observed in GIST-T1 xenografts in mice. Under AFI endoscopy, a strong fluorescence signal was observed in orthotopic GIST xenografts in rats through the normal mucosa covering the tumor. The percentage of dead cells significantly increased in a light-dose-dependent manner and both acute necrotic and late apoptotic cell death was observed with annexin/PI staining. Cleaved PARP expression was significantly increased after IR700-12A8-mediated NIR irradiation, which was almost completely reversed by NaN3. All xenograft tumors (7/7) immediately regressed and 4/7 tumors completely disappeared after IR700-12A8-mediated NIR irradiation. Histologic assessment and TUNEL staining revealed apoptosis in the tumors. Conclusion: NIR fluorescence imaging using IR700-12A8 and subsequent NIR irradiation could be a very effective theranostic technology for GIST, the underlying mechanism of which appears to involve acute necrosis and supposedly late apoptosis induced by singlet oxygen.