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Featured researches published by Naohiro Washizawa.


Journal of The American College of Surgeons | 2008

Reduced Risk of Peristomal Infection of Direct Percutaneous Endoscopic Gastrostomy in Cancer Patients: Comparison with the Pull Percutaneous Endoscopic Gastrostomy Procedure

Naoki Hiki; Iruru Maetani; Yutaka Suzuki; Naohiro Washizawa; Takashi Fukuda; Toshiharu Yamaguchi

BACKGROUND Although pull percutaneous endoscopic gastrostomy (Pull-PEG) is a commonly used procedure, peristomal infection and tumor implantation are considered unavoidable complications of this procedure as the instrument passes through the oral cavity. A novel extracorporeal PEG technique, Direct-PEG, has been developed to reduce the risk of peristomal infection and implantation. STUDY DESIGN The Direct-PEG procedure was performed on 87 patients from April 2006 to April 2007 in a single, high-volume cancer center in Japan. To compare the surgical outcomes of Direct-PEG and Pull-PEG, the clinical outcomes of Direct-PEG, such as peristomal infection, were retrospectively collected and compared with those of 64 patients having Pull-PEG procedures from April 2005 to March 2006. RESULTS The mean operation time for the Direct-PEG group (13+/-1 minutes) was comparable to that for the Pull-PEG group (12+/-1 minutes), and the mean visual analogue pain score during surgery was lower for the Direct-PEG group (3.5+/-1.7) than for the Pull-PEG group (24.6+/-3.6; p < 0.001). The incidence of peristomal infection was lower in the Direct-PEG group (1%) than in the Pull-PEG group (9%; p=0.001). Although the most common major underlying disease in the groups was oropharyngeal or esophageal tumor, tumor implantation was not observed in either group. CONCLUSIONS Direct-PEG may be superior to the Pull-PEG method for a high-volume cancer center because of reduced risks of infection.


Gastric Cancer | 1999

Collision carcinoma at the esophagogastric junction.

Naohiro Washizawa; Kazuo Kobayashi; Hajime Kase; Natsuki Tokura; T. Gotoh; Iwao Iwasaki; Shiro Tsujimoto

Atrue collision carcinoma at the esophagogastric junction is rare. In this article, we report colliding double primary cancers of the esophagus and the stomach in a 68-year-old man and discuss this entity. Pathological analysis after total gastrectomy and partial esophagectomy showed the following findings. Areas of squamous differentiation were found on the esophageal side of the tumor and were adjacent to normal mucosa, and areas of glandular differentiation were found to the gastric side of the tumor and adjacent to normal mucosa. These two tumors collided at the esophago-cardiac junction, but there was no intermingling. In one lymph node, an independent non-intermingled metastatic adenocarcinoma and squamous cell carcinoma were observed. The pathological findings of this case satisfy rigorous criteria for collision carcinoma.


Hepato-gastroenterology | 2012

Evaluation of remnant liver function using 13C-breath tests in a rat model of 70% partial hepatectomy.

Yasuyuki Miura; Naohiro Washizawa; Yoshihisa Urita; Tsunehiko Imai; Hironori Kaneko

BACKGROUND/AIMS A 13C breath test was applied to evaluate the early stage of postoperative liver function after hepatectomy. It was examined in comparison with functional and morphological recovery. METHODOLOGY Rats were subjected to 70% partial hepatectomy (H group) and control group (S group). Expired air, blood and remnant liver tissue were collected at 12, 24, 48 and 72h, and 7 and 14 days postoperatively. Phenylalanine and leucine were used as the 13C-labeled substrates. The 13CO2 was collected until 120min. The mean values of the H and S groups were compared using the highest mean level of 13CO2 excreted in breath (Cmax). The liver regenerative ability was evaluated by Ki-67. RESULTS In the 13C-phenylalanine breath test, the Cmax value tended to be lower for the H group 12h postoperatively (p=0.06). Cmax was significantly lower for the H group 24h postoperatively (p<0.05). Both groups showed equal recovery at 48h postoperatively. In the 13C-leucine breath test, both groups had no significant difference after hepatectomy. The peak of Ki-67 positive rate is estimated to be at 52.8h postoperatively, meaning that the time difference was only approximately 5h between the peak time of Ki-67 positive rate and the 13C-phenylalanine breath test. CONCLUSIONS These results strongly support that the 13C-phenylalanine breath test can become a non-invasive indicator to evaluate the early stage of postoperative liver function after hepatectomy.


Archive | 2018

Reduction of Perioperative Anxiety Before Surgery and to Incentives to Get Well by Patients Themselves

Naohiro Washizawa

Consultation and education before admission to hospitalization are very important items of perioperative management. Anxiety related to surgery has a negative impact on the post-surgery recovery. The goal of a clinical course has to be as clear as a milestone must be understandable, because patients feel safe with that feeling of goal attainment. Surgical patients have to get not only understanding but also satisfaction for preparation to receive the surgical therapy.


Esophagus | 2018

Prognostic significance of high serum p53 antibody titers in patients with esophageal squamous cell carcinoma

Takashi Suzuki; Satoshi Yajima; Nobuki Ishioka; Tatsuki Nanami; Yoko Oshima; Naohiro Washizawa; Kimihiko Funahashi; Seiko Otsuka; Tetsuo Nemoto; Hideaki Shimada

BackgroundThe p53 protein overexpression that usually results from genetic alterations reportedly induces serum antibodies against p53. However, little information is available about the prognostic significance of perioperative serum p53 antibody (s-p53-Abs) titers in patients with esophageal squamous cell carcinoma.MethodsIn this study, we retrospectively evaluated the clinical significance of perioperative s-p53-Abs in 135 patients with esophageal squamous cell carcinoma. Of these, 58 patients received neoadjuvant chemotherapy comprising 5-FU and CDDP. While the cutoff level at 1.3 U/ml indicated seropositive patients, level of 13.4 U/ml was used to identify high-titer patients. We monitored serum titers seropositive patients after surgery and evaluated the prognostic significance by the univariate and multivariate analyses.ResultsIn this study, 29 patients (21.5%) were positive for s-p53-Abs before treatment. The frequency of both seropositive patients and high-titer patients (> 13.4 U/ml) was not significantly associated with tumor progression. While seropositive patients did not demonstrate significant poor overall survival, high-titer patients demonstrated significant poor overall survival based on the multivariate analysis (P < 0.001). Moreover, the s-p53-Abs titer did not correlate with the response to neoadjuvant chemotherapy. Among seropositive patients, the negative conversion of s-p53-Abs more likely led to be long-term survival.ConclusionsThis study determined that the high-titer of s-p53-Abs was an independent risk factor to reduce the overall survival of patients with esophageal cancer patients. The negative conversion of s-p53-Abs could be a good indicator of favorable prognosis.


World Journal of Gastroenterology | 2010

Survival of geriatric patients after percutaneous endoscopic gastrostomy in Japan.

Yutaka Suzuki; Seryna Tamez; Akihiko Murakami; Akihiko Taira; Akihiro Mizuhara; Akira Horiuchi; Chie Mihara; Eiji Ako; Hirohito Muramatsu; Hitoshi Okano; Hitoshi Suenaga; Kazuaki Jomoto; Junya Kobayashi; Katsunari Takifuji; Kazuhiro Akiyama; Koh Tahara; Koji Onishi; Makoto Shimazaki; Masami Matsumoto; Masashi Ijima; Masato Murakami; Masato Nakahori; Michiaki Kudo; Michio Maruyama; Mikako Takahashi; Naohiro Washizawa; Shigeru Onozawa; Satoshi Goshi; Satoyoshi Yamashita; Shigeki Ono


Journal of Surgical Research | 2006

Intestinal anastomosis surgery with no septic shock primes for a dysregulatory response to a second stimulus

Atsushi Kaneko; Toshitaka Kido; Masahiro Yamamoto; Yoshio Kase; Naohiro Washizawa; Masaki Aburada; Shuichi Takeda


Surgery Today | 2016

Hyperfibrinogenemia is associated with inflammatory mediators and poor prognosis in patients with gastric cancer

Takashi Suzuki; Hideaki Shimada; Tatsuki Nanami; Yoko Oshima; Satoshi Yajima; Masaaki Ito; Naohiro Washizawa; Hironori Kaneko


International Journal of Clinical Oncology | 2017

Prognostic significance of hyperfibrinogenemia in patients with esophageal squamous cell carcinoma.

Takashi Suzuki; Hideaki Shimada; Tatsuki Nanami; Yoko Oshima; Satoshi Yajima; Naohiro Washizawa; Hironori Kaneko


Jpn J Gastroenterol Surg, Nihon Shokaki Geka Gakkai zasshi | 1991

Influence of Surgical Stress on the Immunological Activity in the Patients with Gastric Cancer and an Attempt on the Effect of the Early Recovery by the Pre-operative Immunotherapy.

Hajime Kase; Kazuo Kobayashi; Ryoich Honda; Naohiro Washizawa; Yukihiko Satoh; Shigeji Nagasawa; Kenzou Yanagida; T. Yoshio

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