Takamitsu Morikawa

Fujita Health University, Nagoya, Aichi, Japan

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Publications (2)2.86 Total impact

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    ABSTRACT: To evaluate the pathological features of clear cell renal cell carcinoma (CCRCC) treated with tyrosine kinase inhibitors (TKIs), and to elucidate the mechanism of action of TKIs. Twenty cases of CCRCC treated with TKIs (sorafenib or sunitinib) were retrospectively analysed: 16 were patients who had undergone radical nephrectomy after neoadjuvant TKI therapy, and four were autopsy cases of patients who received TKI treatment. All tumours had two distinct regions: one characterized by necrosis and/or degeneration, indicating antitumour activity; and the other characterized by no or few pathological changes, indicating the absence of antitumour activity. Vasculopathy of tumour vessels was observed in or adjacent to the necrotic or degenerative areas; a decreased density of endothelial cells was noted in the tumour vessels. Few or no changes of vasculopathy were observed in tumour vessels in the other CCRCC areas, indicating the absence or low levels of antitumour activity. This is the first pathological report of vasculopathy in TKI-treated CCRCC cases. Our data suggest that TKIs initially induce vasculopathy in tumour vessels, and consequently cause reduction or diminution of blood supply to the CCRCCs, resulting in antitumour activity characterized by necrosis and hyalinization.
    Histopathology 09/2013; · 2.86 Impact Factor
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    ABSTRACT: For the management of patients with small renal tumor, laparoscopic partial nephrectomy (LPN) provides similar oncological control as radical nephrectomy (RN) and is superior to RN with respect to preserving renal function and preventing chronic kidney disease (CKD). The challenge of LPN is to resect a tumor in a bloodless field within a limited warm ischemia time (WIT) , followed by hemostatic renorrhaphy under restricted movement of laparoscopic forceps. Therefore, LPN still remains challenging to even experienced laparoscopic surgeon. DaVinci device improved the movability of forceps in LPN and provided three-dimensional visualization. We evaluated outcome and safety of our first series of robot-assisted laparoscopic partial nephrectomy (RALPN) for localized kidney tumor. There was no previous report of RALPN undertaken in our country. Since August 2010, our team carried out RALPN for a total of five cases of renal tumor. There were four males and one female with an age range of 41 to 65 years-old. Size of tumor ranged from 15 to 28 mm, located in exophytic region, and four cases in right side and one in left. RALPN was undertaken by single surgeon through transperitoneal approach in two cases and retroperitoneal in tree. RALPN was completed in all patients without conversion to open or hand-assisted surgery. The median operative time and the estimated blood loss were 189 minutes, ranged from 150 to 264, and 29 ml, from 10 to 50, respectively. The median volume of removed tumor and the length of WIT were 7 g, ranged from 4 to 13 g, and 18 minutes, from 13 to 26 minutes, respectively. No complications or reoperations were associated during or post our RALPN cases. Pathological examination of removed tumor showed renal cell carcinoma with negative surgical margin in all cases. Introduction of daVinci device to LPN made this procedure, RALPN, a secured and promising one, which leading to shorten the WIT and to achieve satisfied renorrhaphy. Even for the complex and technically challenging renal tumors, robotic assistance is expected to provide patients the benefit of minimally invasive surgery with safety and satisfactory renal function.
    Nippon Hinyōkika Gakkai zasshi. The japanese journal of urology 09/2011; 102(5):679-85.