title: Solitary pulmonary metastasis from prostate cancer with neuroendocrine differentiation: a case report and review of relevant cases from the literature.
abstract: BACKGROUND
  Solitary lung metastasis from prostate cancer is rare. There are few reports of such cases with neuroendocrine differentiation.
  
  
  METHODS
  A 50-year-old man presented to our hospital with a chief complaint of dysuria. Histological examination revealed prostate cancer, which was classified as cT4 N0 M0, stage IV adenocarcinoma. Since the patient was at high risk, endocrine and radiation therapies were started. One year after starting radiation therapy, the patient developed bloody sputum. Chest radiography revealed a nodular shadow in his left lung (S5). Although 18-fluoro-2-deoxyglucose positron emission tomography revealed abnormal accumulation in the lesion, the cytological diagnosis was class IIIa, which did not yield a definitive diagnosis. Given that prostate specific antigen (PSA) was not elevated, a primary lung tumor was suspected, and thoracoscopic segmental resection of the lung was performed with lymph node dissection. The final pathological diagnosis was solitary lung metastasis from prostate cancer with neuroendocrine differentiation and mediastinal lymph node metastasis. The specimen showed a mixed pattern of conventional prostatic and neuroendocrine carcinomas.
  
  
  CONCLUSIONS
  We herein report a case with neuroendocrine differentiation (NED), along with a review of the relevant literature, including histopathological findings. According to previous case reports, some patients with solitary lung metastasis from prostate cancer achieved relatively good long-term survival. We consider establishing the correct diagnosis and implementing an appropriate treatment plan to be essential in prostate cancer patients with oligometastases that have the potential to be neuroendocrine (NE) tumors.
authors.affiliation: Department of Radiology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. m1048@za2.so-net.ne.jp.
authors.forename: Toshiya
authors.initials: T
authors.lastname: Maebayashi
authors.affiliation: Department of Radiology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. m1048toshiya@gmail.com.
authors.forename: Katsumi
authors.initials: K
authors.lastname: Abe
authors.affiliation: Department of Radiology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. aitatata777@hotmail.co.jp.
authors.forename: Takuya
authors.initials: T
authors.lastname: Aizawa
authors.affiliation: Department of Radiology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. sakaguchi.masakuni@nihon-u.ac.jp.
authors.forename: Masakuni
authors.initials: M
authors.lastname: Sakaguchi
authors.affiliation: Department of Radiology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. ishibashi.naoya@nihon-u.ac.jp.
authors.forename: Naoya
authors.initials: N
authors.lastname: Ishibash
authors.affiliation: Department of Radiology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. shfukusi@mx2.nisiq.net.
authors.forename: Shoko
authors.initials: S
authors.lastname: Fukushima
authors.affiliation: Department of Pathology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. honma.taku@nihon-u.ac.jp.
authors.forename: Taku
authors.initials: T
authors.lastname: Honma
authors.affiliation: Department of Pathology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. kusumi.yoshiaki@nihon-u.ac.jp.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Kusumi
authors.affiliation: Department of Urology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. matsui.tsuyoshi@nihon-u.ac.jp.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Matsui
authors.affiliation: Department of Urology, Nihon University School of Medicine, 30-1 Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan. kawata.nozomu@nihon-u.ac.jp.
authors.forename: Nozomu
authors.initials: N
authors.lastname: Kawata
mesh_terms: D018278:Carcinoma, Neuroendocrine / Q000556:secondary*; D002454:Cell Differentiation; D006801:Humans; D008175:Lung Neoplasms / Q000556:secondary*; D008297:Male; D008479:Mediastinal Neoplasms / Q000556:secondary*; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000473:pathology*