Biomedical subjects
Gen Kawa
Publications and source records attributed to Gen Kawa.
Retroperitoneoscopic pyeloplasty: using reconstructive methods based on intraoperative findings.
AIM: Reconstructive laparoscopic procedures have been recognized as a less invasive treatment than conventional open procedures. However, although the laparoscopic pyeloplasty has also been accepted as useful, few findings have been reported relevant to the retroperitoneal approach. To elucidate its effectiveness and safety, laparoscopic surgery via the retroperitoneal approach was examined in our institution. Furthermore, the importance of laparoscopic observation for ureteropelvic junction and urine passage ureteropelvic junction without indwelling ureteral stent. METHODS: Between July 1998 and December 2004, 13 men and 15 women underwent laparoscopic retroperitoneal surgery for ureteropelvic junction obstruction. The mean patient age was 33.6 years (range: 13-70 years). Methods of repair were determined by intraoperative findings for the relationship between the ureteropelvic junction and surrounding vessels. An indwelling ureteral stent was removed before initiating laparoscopic operation to observe the relationship between ureteropelvic junction and aberrant vessels more precisely. RESULTS: An aberrant renal vessel was found in 13 patients (46%). Dismembered pyeloplasty was carried out in 21 patients, Y-V plasty in five patients and Hellstrom technique in two patients. Ureteral transposition was not required in dismembered pyeloplasty cases. All patients achieved retroperitoneoscopic pyeloplasty without open conversion. The mean operative time was 272 min (range: 155-490 min). The mean estimated blood loss was 44 mL (range: 10-200 mL). No major complications were observed during the intraoperative period, but urinary tract infection occurred in two patients in the postoperative period. In all patients except one, obstruction was improved or resolved. CONCLUSIONS: Laparoscopic retroperitoneal surgery is not only able to repair ureteropelvic junction obstruction, but can also be done safety and less invasively. We believe that laparoscopic observation without indwelling stent will contribute to a more appropriate choice of pyeloplasty.
[Experience of laparoscopic nerve-sparing radical cystectomy and construction of ileal neobladder at Kansai Medical University].
Laparoscopic nerve-sparing radical cystectomy and construction of ileal neobladder was performed on a 76-year-old man with atrophic bladder after the intravesical instillation therapy for bladder cancer. Ileal neobladder was constructed by the combined extracorporeal technique through the camera port dilated to 45 mm. Operation time was 8 hours, with 3.5 hours for the nerve-sparing cystoprostatectomy, 2.5 hours for the extracorporeal neo-bladder construction and 2 hours for the laparoscopic urethra neo-bladder anastomosis and wound closing. The post-operative course was uneventful with minimum use of analgesia. This operation was minimally invasive therapy and from the functional aspect the potency was preserved. Although this method was technically challenging, various advantages can be promising for the patients compared to the standard open technique. Indication of this operation should be carefully expanded. Various methods, such as the complete intracorporeal technique and minimally invasive laparoscopic neobladder (MILaN) technique, have been reported for urinary diversion. In this report, we compared our method with other techniques.
Retroperitoneoscopic partial nephrectomy with transient occlusion of renal artery for treatment of small renal tumors.
OBJECTIVES: To evaluate the results of retroperitoneoscopic partial nephrectomy with transient occlusion of the renal artery for treatment of patients with small renal tumors. METHODS: From May 2002 to March 2003, 12 consecutive patients with T1N0M0 renal tumors with a median diameter of 3.0 cm underwent retroperitoneoscopic partial nephrectomy. The renal artery was clamped transiently without occlusion of the renal vein and the tumor was excised with scissors. Intracorporeal renal cooling was achieved by cold saline perfusion of the renal pelvis through a single-J ureteral catheter. Hemostasis was achieved by approximating the renal parenchyma over the perirenal fatty tissue using a retroperitoneoscopic suturing technique. RESULTS: Of the 12 patients, 11 successfully underwent partial nephrectomy retroperitoneoscopically. The median operative time, renal ischemic time, and amount of blood loss in the successful procedures was 220 minutes (range 132 to 340), 50 minutes (range 16 to 115), and 150 mL (range 50 to 800), respectively. The renal calix was opened and repaired in 10 patients. The surgical margin was negative in all patients. The postoperative course was uneventful in all patients, and the return to work was achieved in a median of 18 days (range 9 to 39). The renal function of the affected kidney was well preserved postoperatively, when examined by renal scintigraphy. Neither local recurrence nor distant metastasis was found during the median follow-up period of 10 months (range 1 to 18). CONCLUSIONS: Retroperitoneoscopic partial nephrectomy with transient occlusion of the renal artery is a useful and less-invasive method for resection of small renal tumors. Additional technologic developments to reduce ischemic times and to cool the kidneys laparoscopically are required.
[A clinical analysis of patients with early-stage prostate cancer managed without initial treatment].
To search for a more suitable qualification indicating watchful waiting, we performed a retrospective study against early-stage prostate cancer patients managed without initial treatment. Thirty-three patients who had not been treated for more than 6 months after diagnosed as T1c or T2 prostate cancer were studied. The median values of total observation period, age at diagnosis, and initial PSA were 27.0 months, 69.0 years old, and 7.0 ng/ml, respectively. Among 28 patients who had had measurement of serum PSA at least three times, seven patients showed a significant PSA elevation when transition of PSA level was analyzed using linear regression analysis. The other patients had been stable or PSA level declined. Between these two groups, there was no significant difference regarding age, initial PSA, PSA density, Gleason score, number of cancer-positive core, and cancer-occupying rate in biopsy specimen. The median PSA doubling time in patients showing PSA elevation was 36.3 months. There were no patients showing PSA elevation among those with a cancer-occupying rate of less than 5%. Clinical disease progression was obviously observed in two cases although one did not show PSA elevation. During the observation period, treatment was eventually started in seven patients. The 5-year rate of no treatment was 53.8%. Although a significant independent factor predicting the future treatment was not identified, univariate analysis revealed that the initial PSA value in patients undergoing treatment was significantly higher than that of those without treatment (p = 0.032). We concluded that early-stage prostate cancer has clinical variability, and regular clinical evaluations as digital rectal examination should be performed when the patient was managed with watchful waiting.
The effect of eicosapentaenoic acid on prostate-specific antigen.
The "Study of EPA Effects on Prostate Cancer" (SEEPC) Group has been conducting a clinical trial with patients who underwent radical prostatectomy. The main purpose of the SEEPC is to evaluate whether eicosapentaenoic acid (EPA) prevents prostate cancer (PC) recurrence. As the surrogate marker of recurrence, the prostate-specific antigen (PSA) level was measured. However, if EPA affects the PSA values independently of PC, PSA may not be a good marker of recurrence in the event of EPA treatment. Thus, in the present study, whether EPA affected the PSA values was investigated using non-PC volunteers. Twenty men, of at least 50 years of age, were recruited, mostly from hospital staff The volunteers were randomly allocated either to the EPA group or the control. The subjects in the EPA group were administered EPA-ethyl ester a dose of 2400 mg/day for 12 weeks, whereas the controls were administered none. Fasting blood samples were obtained before the start of EPA administration and 4 and 12 weeks later. The EPA concentrations in erythrocytes increased in all the subjects in the EPA group (174+/-96%) with no significant changes in the control group (8.5+/-14.0%). There were no significant differences between the two groups in the serum PSA levels, allowing the conclusion that the PSA is an appropriate surrogate marker of recurrence in prostate cancer.