Yasuyuki Shimoyama: Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, 3-39-15 Showamachi, Maebashi, Gunma, 371-8511, Japan. yshimoya@showa.gunma-u.ac.jp.
Motoyasu Kusano: Department of Endoscopy and Endoscopic Surgery, Gunma University Hospital, Maebashi, Japan.
Yoko Shimoda: Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, 3-39-15 Showamachi, Maebashi, Gunma, 371-8511, Japan.
Shingo Ishihara: Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, 3-39-15 Showamachi, Maebashi, Gunma, 371-8511, Japan.
Yoshitaka Toyomasu: Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Japan.
Tetsuro Ohno: Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Japan.
Erito Mochiki: Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Japan.
Takaaki Sano: Department of Diagnostic Pathology, Gunma University Graduate School of Medicine, Maebashi, Japan.
Junko Hirato: Department of Pathology, Gunma University Hospital, Maebashi, Japan.
Masatomo Mori: Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, 3-39-15 Showamachi, Maebashi, Gunma, 371-8511, Japan.
A 74-year-old man had an endoscopic type 0'-IIc tumor in the upper gastric body on the greater curvature and biopsy showed the tumor to be a well-differentiated adenocarcinoma (Group 5). He was referred to us for endoscopic submucosal dissection (ESD). Endoscopy revealed fold convergency, fold swelling, and fusion of the fold, indicating tumor invasion into the submucosa, which was outside the indications for ESD. In addition, there was an increase of serum bone-type alkaline phosphatase (ALP-III and ALP-IV) and urinary cross-linked N-terminal telopeptide of type I collagen (a bone metabolism marker), while (18)F-fluorodeoxyglucose positron emission tomography showed increased uptake in the left pelvis and Th10, suggesting bone metastases. We first diagnosed gastric cancer with bone metastases; however, the symptoms suggested pathological bone fracture and no bone pain. Therefore, a computed tomography-guided aspiration bone biopsy was performed to exclude the possibility of Paget's disease of bone. Biopsy specimens revealed no tumor and a mosaic pattern. No increased uptake of (18)F-FAMT (L-[3-(18)F] α-methyltyrosine) supported a diagnosis of no bone metastases from gastric cancer. We finally diagnosed gastric cancer accompanied by Paget's disease of bone and performed a laparoscopy-assisted proximal gastrectomy. The pathological diagnosis was U less 0-IIb, and U post 0-IIc ypT1a (M) N0H0P0M0 yp stage IA. In gastric cancer patients with suspected bone metastasis, we also need to consider Paget's disease of bone.
