Biomedical subjects

Yuichiro Doki

Publications and source records attributed to Yuichiro Doki.

46 records · Page 3Linked to original sources

PubMed2003

Postoperative cytology for drained fluid from the pancreatic bed after "curative" resection of pancreatic cancers: does it predict both the patient's prognosis and the site of cancer recurrence?

OBJECTIVE: To evaluate the postoperative cytology of drained fluid from the pancreatic bed as a predictive indicator of local recurrence after curative (R0) resection of pancreatic cancer. SUMMARY BACKGROUND DATA: The pancreatic bed offers a common site of cancer recurrence (local recurrence), even after curative (R0) resection is performed for pancreatic cancer. If local recurrence is thereby predicted precisely, soon after surgery, we have a chance to treat it by adding radiation or some other locoregional therapy before it can grow or spread beyond the pancreatic bed. However, there have been no previous reports of cytology performed on the drained fluid after pancreatectomy. METHODS: This study includes 94 patients who had shown negative results in the peritoneal washing cytology before resection and subsequently received pancreatectomies for pancreatic tumors. They consisted of 12 benign tumors, 17 noninvasive or minimally invasive carcinomas and 65 invasive ductal carcinomas (R0 = 58; R1/2 = 7). Postoperatively, the drained fluid from the pancreatic bed was collected for 24 hours and used for cytologic examination. The cytologic results were examined in association with the histopathology of the resected tumor, patient's survival, and mode of cancer recurrence, including local recurrence. RESULTS: Patients with benign tumors or noninvasive/minimally invasive carcinomas had negative result in cytology, and none of them have died of local recurrence (limited to the pancreatic bed) to date. However, patients with invasive ductal carcinoma revealed higher cytology-positive rates: 28% (16/58) in curative (R0) resection; and 71% (5/7) in noncurative (R1/2) resection. Among 58 patients with R0 resection, the 3-year survival rate was 14% in 16 cytology-positive patients and 55% in 42 cytology-negative patients (P < 0.05). The 3-year cumulative rate of local recurrence was 85% and 23%, respectively (P < 0.05). Compared with other histopathologic parameters obtained from the resected specimens, the drain cytology was more specific in predicting the subsequent development of local recurrence. CONCLUSIONS: Drain-cytology was a quick examination that enabled us to specifically indicate both minute residual cancer and subsequent development of local recurrence even after R0 resection of pancreatic cancer.

Adenocarcinoma↗

PubMed2002

Neoadjuvant chemotherapy followed by salvage surgery: effect on survival of patients with primary noncurative gastric cancer.

The prognosis for gastric cancer patients who undergo noncurative resection is extremely poor. This study evaluated the effects of neoadjuvant chemotherapy for primary noncurative gastric cancer. Thirty-four patients with biopsy-proven noncurative gastric cancer were treated with either of two neoadjuvant chemotherapies: FEMTXP (5-fluorouracil, epirubicin, methotrexate, cisplatin) or THP-FLPM (pirarubicin, 5-fluorouracil, leucovorin, cisplatin, mitomycin C). Noncurability was determined by conventional staging procedures, staging laparoscopy, and exploratory laparotomy. After chemotherapy the resectability of the tumors was reassessed. Patients who were judged to be candidates for curative resection underwent salvage surgery. Of the final 33 patients, 8 (24.2%) showed a major response [0 complete response (CR), 8 partial response (PR)]. In three patients the second laparoscopy revealed disappearance of the peritoneal metastasis. Of the 33 patients, 14 (42.4%) underwent salvage surgery, including 8 curative resections (2 curability A, 6 curability B). Pathologic examinations revealed a grade 2 response in eight patients but no grade 3 response. Univariate analysis showed the following to be significant prognostic factors: histology type (differentiated type vs. undifferentiated type; p = 0.035), T4 as a noncurative factor (T4 vs. T3 or less; p = 0.025), clinical response (PR + no change vs. progressive disease; p = 0.002), and salvage surgery (resected vs. unresected; p = 0.001). Among these factors, salvage surgery was found to be the only independent prognostic factor by multivariate analysis, with a relative risk of 0.253 and a 95% confidence interval of 0.066 to 0.974. The treatment was well tolerated. Major toxicities of WHO grade 3 or more were leukopenia in 20 (60.6%), gastrointestinal toxicities in 5 (15.2%), renal toxicities in 2 (6.1%), and alopecia in 1 (3.0%). In conclusion, neoadjuvant chemotherapy is effective for primary noncurative gastric cancer when salvage surgery can be performed. A chemotherapy regimen with a higher complete response rate would improve the prognosis of this dismal disease even more.

Adult↗

PubMed2002

A multi-institutional study of immunohistochemical investigation for the roles of cyclin D1 and E-cadherin in superficial squamous cell carcinoma of the esophagus.

BACKGROUND AND OBJECTIVES: Aiming to clarify and possibly extend indications for minimally invasive treatment, we characterized superficial esophageal cancers (SEC) with respect to biologic properties regulating malignant potential. METHODS: Surgical specimens obtained at eight cancer institutes from 222 Japanese patients with SEC (all squamous cell carcinomas) were investigated immunohistochemically for expression of cyclin D1 and E-cadherin. RESULTS: Perturbations of cyclin D1 (overexpression) and E-cadherin (reduced expression) were observed in 37.6% (68 of 181) and 39.9% (71 of 178) of SEC patients. E-cadherin expression was more frequently reduced in cancers that invaded the submucosal layer, while cyclin D1 overexpression was constant, irrespective of depth of invasion. Overexpression of cyclin D1 was more frequent in poorly differentiated squamous cell carcinomas, while E-cadherin did not vary according to histologic differentiation. Lymph node metastasis, the only independent postoperative prognostic factor in these patients, occurred in only 4.8% of mucosal cancers (2 of 42), but in 51.1% of submucosal cancers (92 of 180). However, neither cyclin D1 nor E-cadherin status affected lymph node metastasis. CONCLUSION: Both E-cadherin and cyclin D1 play important roles in esophageal carcinogenesis, but neither can be used to identify patients who do not require lymph node dissection and might be treated by endoscopic mucosal resection.

Cadherins↗

PubMed2002

Cytokeratin deposits in lymph nodes show distinct clinical significance from lymph node micrometastasis in human esophageal cancers.

BACKGROUND: Cytokeratin immunostaining is the most common method used to identify micrometastatic cancer cells from the lymph nodes. However, contamination with hyalinized cytokeratin particles, frequently observed in the lymph nodes of esophageal cancer patients, can lead to misinterpretation of cytokeratin immunostaining. MATERIALS AND METHODS: Cytokeratin immunostaining (AE1/AE3) of surgically removed lymph nodes was performed for 41 cases of node-negative, but locally advanced (T3, T4), esophageal cancer patients. Cytokeratin immunoreactivity (CK) was classified as micrometastasis (MM) or cytokeratin deposit (CD) by the presence or absence of tumor nuclei in serial sections given hematoxylin-eosin staining. RESULTS: CK (+) was observed in 18 patients (44%), including 11 with MM (+) (27%) and 10 with CD (+) (24%). There was no correlation between MM and CD, and neither was associated with clinicopathological factors, except for a high incidence of preoperative chemotherapy in CD (+) patients. The presence of CK did not affect postoperative survival of esophageal cancer patients at this limited stage, showing a 5-year survival rate of 57% for CK (+) and 64% for CK (-) (P = 0.6064). Interestingly, patients with MM (+) showed poorer prognosis than MM (-) (5-year survival: 28% vs 79%, P = 0.0188), while CD (+) patients tended to display better prognosis than CD (-) ones (5-year survival: 78% vs 56%, P = 0.1860). CONCLUSIONS: Evaluation by cytokeratin immunostaining of lymph nodes requires careful discrimination of CD from MM, in order to allow MM to be used as a prognostic factor for esophageal cancer patients.

Esophageal Neoplasms↗

PubMed2000

Clinical significance of disordered beta-catenin expression pattern in human gastric cancers.

BACKGROUND: Beta-catenin plays two distinct roles, in intercellular adhesion by E-cadherin, and in transcriptional activation via TCF/LEF. Theoretically, the former role is tumor-suppressive, while the latter is oncogenic. We investigated the involvement of beta-catenin in the histogenesis and clinical outcome of gastric cancers.METHODS: The expression pattern of beta-catenin was evaluated in stomach and lymph nodes from 82 patients with gastric cancer by immunohistochemistry and Western blot. Its association with E-cadherin expression and clinicopathological factors, including histological type and postoperative survival, was examined.RESULTS: Beta-catenin expression was classified into two patterns, normal (23.2%; 19 patients) and disordered (76.8%; 63 patients), the latter being subclassified as overexpressed (7.3%; 6 patients) and reduced (69.5%; 57 patients). A disordered beta-catenin expression pattern was significantly correlated with diffuse type adenocarcinoma and deep tumor infiltration ( P = 0.0154), but was not associated with lymph node metastasis ( P = 0.7877). E-cadherin was always expressed at the cell membrane, and disordered beta-catenin expression was significantly associated with reduced E-cadherin expression ( P < 0.0001). On univariate analysis, the beta-catenin pattern, as well as depth of invasion and lymph node metastasis, was associated with postoperative prognosis; however, only lymph node metastasis was an independent prognostic factor on multivariate analysis. Interestingly, different disordered patterns of beta-catenin expression, both overexpressed and reduced, were associated with E-cadherin reduction and poorer postoperative survival.CONCLUSION: Although disordered patterns of beta-catenin expression varied in gastric cancers, they were consistently associated with cancer progression.

Journal Article↗

PubMedDate not supplied

Overexpression of cyclin DI contributes to malignant properties of esophageal tumor cells by increasing VEGF production and decreasing Fas expression.

Cyclin D1 is frequently overexpressed in human esophageal cancer. We examined the possible role of cyclin D1 overexpression on specific malignant properties of tumor cells using a series of eight human esophageal cancer cell lines that express different levels of cyclin D1. We did not find a simple correlation between levels of cyclin D1 expression and anchorage-independent growth, production of angiogenic factors, or tumorigenicity in nude mice, suggesting that other factors can influence these parameters. We did, however, obtain evidence that tumorigenicity appeared to require both the capacity for anchorage-independent growth and the production of angiogenic factors. To better assess the specific role of cyclin D1, we stably expressed an antisense cyclin D1 cDNA construct in the tumorigenic cell line TTn. This significantly decreased anchorage-independent growth and VEGF production and led to a loss of tumorigenicity in nude mice. Furthermore, these cells diplayed a marked increase in sensitivity to antitumor agents and to Fas antibody-induced apoptosis. Taken together, these findings suggest that the overexpression of cyclin D1 can confer esophageal cancer cells with enhanced malignancy through increases in anchorage-independent growth and VEGF production, and down-regulation of Fas expression, thus suggesting novel functions of the cyclin D1 protein in tumor progression.

Animals↗

PubMedDate not supplied

Practical usefulness of bipolar scissors in hepatectomy.

BACKGROUND/AIMS: Because less surgical stress might preserve quality of life of patients, it is more desirable to decrease both intraoperative blood loss and liver injury especially in hepatectomy. For the patients with hepatocellular carcinoma based on chronic liver dysfunction, it is more essential to control bleeding and reduce liver injury in hepatectomy than in other diseases. In the present study, a retrospective comparison about usefulness was made in hepatectomy between using bipolar scissors and using conventional procedure. Before 1997, in our hospital, we had dissected the liver by using the crushing clamp method in combination with cauterization by microwave coagulator for the purpose of reducing intraoperative blood loss. Since 1998, bipolar scissors have been introduced toward hepatectomy as a new, simple and easy device to use. METHODOLOGY: Fifty-three consecutive patients with primary hepatocellular carcinoma at TNM stage I/II who underwent partial hepatectomy between 1996 and 1999 were enrolled in the study. Thirty-two patients (1996-1997) were treated by using a conventional method (group CM) and 21 patients (1998-1999) were treated by using bipolar scissors (group BS). The factors related to surgical stress were compared between the two groups. RESULTS: The amounts of blood loss/transfusion were lower in group BS (641/100 mL) than in group CM (1112/450 mL). The percentages of patients who lost more than 1000 mL of blood were lower in group BS (19%) than in group CM (47%) (P = 0.04). An intraabdominal drainage was needed for 9.0 +/- 6.6 days in group BS, and the drainage period was shorter than that in group CM (15.0 +/- 8.7 days) (P = 0.01). CONCLUSIONS: These results indicated the superiority of bipolar scissors in decreasing blood loss and liver injury to the conventional method, suggesting the worth of performing the prospective randomized study.

Aged↗

PubMedDate not supplied

Early ligation of the inferior pancreaticoduodenal artery to reduce blood loss during pancreaticoduodenectomy.

When performing a pancreaticoduodenectomy, a considerable amount of congested blood is lost, especially during the period when the pancreatic head area is being isolated from the superior mesenteric vessels. Following Kocher's maneuver, a 4-cm dissection was continued along the right margin of the superior mesenteric artery. The root of the inferior pancreaticoduodenal artery was disclosed and ligated prior to the following resection procedures. The early ligation of the inferior pangreaticoduodenal artery decreased blood loss (from 194+/-24 mL to 86+/-50 mL) during the period when the pancreatic head area was isolated from the superior mesenteric vessels. This approach was feasible in reducing blood loss presumably related to blood congestion.

Aged↗

PubMedDate not supplied

Surgery for hepatocellular carcinoma with tumor thrombus extending into the right atrium: report of a successful resection without the use of cardiopulmonary bypass.

Hepatocellular carcinomas, of which the tumor thrombus extends into the right atrium via the inferior vena cava, may soon cause fatal complications. Only surgery can be an effective treatment. This procedure usually needs the aid of cardiopulmonary bypass. We recently experienced a successful surgery to remove thrombus combined with hepatectomy. Reporting the detailed technique, both associated diagnosis and intraoperative management are discussed herein. We were able to perform hepatectomy of tumor thrombus in the right atrium without the use of cardiopulmonary bypass or veno-venous bypass. The tumor thrombus was removed from the right atrium into the suprahepatic inferior vena cava by reducing the liver on the tail side. And after total hepatic vascular exclusion was achieved, the intracaval tumor thrombus and the right lobe of the liver were removed en bloc. The operation took 545 minutes and the total hepatic vascular exclusion period was 32 minutes. The postoperative course was uneventful. There are some key points for this procedure. Preoperative or intraoperative US is essential in judging whether tumor thrombus can be removed from the right atrium into the inferior vena cava by reducing the liver or not. Test clamping of the inferior vena cava prior to total hepatic vascular exclusion will enable us to judge whether veno-venous bypass during total hepatic vascular exclusion is needed or not. Surgery without the use of cardiopulmonary bypass is safe and can be minimally invasive when it is performed with a reliable diagnosis and technique.

Carcinoma, Hepatocellular↗

PubMedDate not supplied

Successful preoperative treatment for hepatocellular carcinoma with tumor thrombus in the major portal branch by three-dimensional conformal radiation therapy--two case reports.

The prognosis of hepatocellular carcinoma (HCC) patients with tumor thrombus in the main portal branch (PVTT) is very poor and a standard treatment regimen for HCC with PVTT has not yet been established. Therefore, a new strategy is necessary to control the patients of HCC with PVTT. Conventional radiation therapy for HCC was not effective because of low liver tolerance. On the other hand, because three-dimensional conformal radiation therapy (3D-CRT) can focus high-dose irradiation on a small area, we tried it for patients with PVTT as the preoperative adjuvant treatment. 3D-CRT which targeted the PVTT was performed for two HCC patients with PVTT before radical hepatectomy. Treatment schedules of 3D-CRT were as follows: in Case 1, the daily fraction size was 3 Gy, given five times per week, and the total dose was 39 Gy. In Case 2, the daily size was 6 Gy and the total dose was 60 Gy. Three or four weeks after 3D-CRT, the main tumor and PVTT were completely removed. On histological examination, the PVTT showed complete necrosis in Case 1, and 60% necrosis in Case 2. No serious complications occurred, and there have been no recurrences for more than one year after surgery in both cases. 3D-CRT targeting the PVTT may be promising as a preoperative adjuvant therapy for HCC with PVTT.

Aged↗