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W K Yuen

Publications and source records attributed to W K Yuen.

34 records · Page 2Linked to original sources
PubMed1998

Hepatic cryosurgery for recurrent hepatocellular carcinoma after hepatectomy: a preliminary report.

BACKGROUND AND OBJECTIVES: The treatment of choice for recurrent hepatocellular carcinoma (HCC) is repeated resection. However, only a small percentage of patients are suitable for further hepatic resection. The aim of this study was to evaluate the surgical risk and operative outcome of hepatic cryosurgery in patients with recurrent HCC. METHODS: A retrospective analysis of patients with recurrent HCC after previous curative hepatectomy treated with cryosurgery. Four patients with recurrent HCC not suitable for further resection were enrolled for cryosurgery, their clinical parameters, the operative details and outcome were studied. RESULTS: No intraoperative or postoperative complications were noted. The duration of operation ranged from 3-5.2 hr and the operative blood loss from 173-1,300 ml. All patients are still alive with survival after cryosurgery ranging from 12-23 mo (25-63 mo after the hepatic resection). Three patients showed evidence of recurrent disease and one patient was disease free. CONCLUSIONS: Hepatic cryosurgery is a safe therapy for patients with unresectable recurrent HCC.

Carcinoma, Hepatocellular↗
PubMed1998

Prolonged survival in selected patients following surgical resection for pulmonary metastasis from hepatocellular carcinoma.

BACKGROUND: Pulmonary metastasis is the commonest site of extrahepatic spread from hepatocellular carcinoma (HCC). The aim of the present study was to evaluate the efficacy of surgical management in patients with solitary pulmonary metastases from HCC. METHODS: This was a retrospective study of patients with HCC admitted for hepatectomy from July 1972 to June 1995. The records of patients who had a pulmonary resection for histologically proven pulmonary recurrence after curative hepatectomy were selected for analysis. RESULTS: In the study interval, 380 patients with HCC underwent hepatectomy. Some 48 patients (12.6 per cent) developed pulmonary metastases documented pathologically or radiologically. Nine (seven men and two women) were suitable for curative pulmonary resection. The median disease-free survival between hepatectomy and appearance of the lung metastasis was 21 months. The median survival after pulmonary resection was 42 months, and the 1-, 2- and 5-year survival rates were 100, 78 and 67 per cent respectively. CONCLUSION: Pulmonary resection for metastases from HCC resulted in long-term survival in these highly selected patients.

Adult↗
PubMed1994

Mesenchymal hamartoma of liver in a man: comparison with cases in infants.

A 53 year old man with a large mesenchymal hamartoma is reported. Only a few bile ducts could be found in the periphery of the lesion and no hepatocytes were identified within the lesion. As far as is known, this is the only adult male patient reported to date. On the basis of the reported findings of mesenchymal hamartoma in other adults, it is suggested that there could be changes in the morphology of this lesion with age: progressive loss of hepatocytes; degeneration of bile duct epithelium; and cystic change of the mesenchymal component. The haematopoietic element is considered to be part of the fetal hepatic haematopoiesis that occurs in the hamartoma.

Hamartoma↗
PubMed1993

Treatment of inoperable hepatocellular carcinoma by transcatheter arterial chemoembolization using an emulsion of cisplatin in iodized oil and gelfoam.

Eighty patients with inoperable hepatocellular carcinoma (HCC) were treated by transcatheter arterial chemoembolization using an emulsion of Lipiodol and Cisplatin. In 59 patients, gelfoam embolization was also given. The tumour size ranged from 0.5 cm to 33 cm in maximum diameter with the median diameter being 8 cm. The chemoembolization sessions were repeated every 1 1/2 to 3 months. The number of sessions the patients underwent varied from 1 to 11, with the mean number of sessions being 3.7. The HCC either disappeared completely or decreased in size in 44 patients (55%). In patients having an HCC of 12 cm or less in size, 31 out of 41 (75.6%) who had the addition of gelfoam demonstrated decrease in tumour size, while seven out of 11 (63.6%) without the addition of gelfoam demonstrated decrease in tumour size. In patients having an HCC of more than 12 cm in size, only six out of 18 (33.3%) who had the addition of gelfoam demonstrated reduction in tumour size and none of the 10 patients without the addition of gelfoam responded. Thus, HCCs of 12 cm or less in size responded better than larger ones to chemoembolization (P < 0.0001) while the addition of gelfoam enhanced the response (P = 0.039). The 1 year survival rate for the 80 patients was 53% and the 2 years survival rate was 38%. The median survival was 13 months. For patients having an HCC of 12 cm or less in size, the 1 year and 2 year survival rates were 69% and 47% respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Bleeding angiodysplasia of the gastrointestinal tract.

Bleeding angiodysplasia of the gastrointestinal tract poses frustrating challenges to clinicians because these minute vascular lesions are difficult to diagnose pre-operatively and to locate intra-operatively. During the past 12 years, 24 patients were treated for histopathologically confirmed bleeding angiodysplasia of the gastrointestinal tract. Pre-operative investigations and intra-operative localization followed a fixed protocol for patients with gastrointestinal bleeding of obscure origin. The median follow-up of these 24 patients was 51 months and the results of treatment for 22 patients were excellent. Two patients had recurrent bleeding but investigations failed to determine the bleeding source.

Adult↗
PubMed1992

Obscure bleeding in the gastrointestinal tract originating in the small intestine.

In the past 12 years, we operated upon 49 patients with bleeding lesions of the small intestine. After endoscopic examination and barium studies of the upper and lower gastrointestinal tract excluded esophagogastroduodenal and lesions of the colon and rectum, preoperative examinations consisted of technetium-99m pertechnetate scan, technetium-99m labeled erythrocyte scan, barium studies of the small intestine and selective visceral angiogram. In one patient, diagnostic laparotomy had to be done before any procedure because of severe bleeding and angiosarcoma of the ileum. The results of gross examination at operation revealed bleeding lesions in 40 patients. Special intraoperative localization procedures consisting of methylene blue injection through superselectively prepositioned angiographic catheter was done on eight patients, and intraoperative enteroscopy was done on 17 patients. These two procedures were complementary, having their own indications and limitations. Our regimen of preoperative and intraoperative localization procedures was effective in the management of bleeding small intestinal lesions.

Adolescent↗
PubMed1991

Operative choledochoscopy in patients with acute cholangitis: a prospective, randomized study.

A prospective, randomized evaluation of operative choledochoscopy was carried out during emergency surgery in patients with acute cholangitis or acute suppurative cholangitis when conservative management had failed. After common bile duct exploration, 79 patients were randomized to have choledochoscopy and 78 patients to the control group. Laboratory and clinical parameters showed that choledochoscopy did not increase the incidence of septicaemia, acute pancreatitis, persistent cholangitis, postoperative wound sepsis, intraperitoneal sepsis and hospital mortality. The incidence of retained common bile duct stones detected by T tube cholangiography performed in the second postoperative week was significantly reduced (P less than 0.01) after choledochoscopy. Choledochoscopy detected stones missed by conventional common bile duct exploration in ten patients. It is concluded that choledochoscopy is a safe and effective technique in patients with acute cholangitis and acute suppurative cholangitis.

Acute Disease↗
PubMed1990

Systemic antibiotic regimens for acute cholecystitis treated by early cholecystectomy.

A total of 203 patients were randomized into a prospective trial to compare short (SC) versus long courses (LC) of systemic antibiotic for acute cholecystitis treated by early cholecystectomy. The initial pre-operative management was the same and all patients received 2 g of cefamandole intravenously just before operation. Two further doses of cefamandole 500 mg were given 6 and 12 h later for patients on SC while the antibiotic was continued at 500 mg at 6 h intervals for 7 days for patients on LC. Seven patients developed wound infection on SC compared with five patients with wound infection and an additional patient with a subphrenic abscess on LC (P greater than 0.05). Thrombophlebitis related to intravenous antibiotic injections was more common in patients on LC (P less than 0.05). Also, patients on LC had to stay statistically longer in hospital in order to complete the course of antibiotic (P less than 0.05). We therefore recommend a SC to be used, as it is more cost-effective and causes fewer complications.

Acute Disease↗
PubMed1989

Repeat selective visceral angiography in patients with gastrointestinal bleeding of obscure origin.

In the past 9 years, we have operated on 56 patients with gastrointestinal bleeding of obscure origin. Selective visceral angiography demonstrated the bleeding lesions in 24 of the 30 patients who underwent this investigation. Six of these 24 patients, however, had a negative angiogram initially and the lesions were only demonstrated on a repeat angiogram. The negative initial angiograms were due to: (1) slow bleeding from lesions in two patients; (2) a small bleeding tumour that caused only intermittent jejunojejunal intussusception in one patient; (3) technical fault in one patient; and (4) spasm of the bleeding vascular lesions and their feeding arteries in two patients. We advocate repeat angiography the following day in all patients in whom profuse bleeding continues, and during the next intestinal bleeding in those whose bleeding stops after the initial negative angiography. In patients who have repeated episodes of massive bleeding, and in whom full investigations fail to reveal the bleeding source, repeat angiography carried out 4 weeks after the bleeding has stopped can sometimes demonstrate the vascular lesions.

Angiography↗
PubMed1989

Regional metal concentrations in Parkinson's disease, other chronic neurological diseases, and control brains.

Metal deficiency or toxicity states have been recognized as a cause of several neurological disorders and are suspected in others. We analyzed four brain regions (frontal cortex, caudate nucleus, substantia nigra, and cerebellum) in 36 human brains for concentrations of 24 metals (Ag, Al, As, B, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Pb, Mg, Mn, Mo, Na, Ni, P, Se, Ti, V, W, Zn). Regional metal concentrations, measured using atomic absorption and atomic emission spectroscopy, were compared between 9 Parkinson's disease (PD) brains, 15 brains from patients with other chronic neurological diseases, and 12 control brains. No significant metal concentration differences were noted between brains from PD and other chronic neurologic disease. However, parkinsonian brains (PD and parkinsonism secondary to neurofibrillary tangle disease) showed lower concentrations of magnesium in the caudate nucleus and copper in the substantia nigra than control brains. These findings may represent an etiologically important clue to parkinsonism.

Aged↗
PubMed1989

Intraoperative enteroscopy for bleeding angiodysplasias of small intestine.

Six patients with angiodysplasias of the small intestine were diagnosed preoperatively with selective angiography during the past eight years. Enteroscopy was used to identify these vascular lesions intraoperatively. Lesions were ulcerated in four patients, had a bleeding vessel tip in one patient and appeared as a nonulcerated reddish patch in the other. Exact localization of these lesions allowed limited segmental resection of the small intestine to be performed. With complete enteroscopy, we were confident that no bleeding lesion was left undetected. The feeding artery and vein to the resected intestinal segment were separately cannulated, and the resected specimen was prepared and injected with hot barium-gelatine. The lesions were confirmed histopathologically to be angiodysplasias in all six patients. There was no recurrence of gastrointestinal bleeding at a median follow-up study of 34 months. There were no operative deaths, and no complications arose from enteroscopy.

Adult↗
PubMed1987

Geography, drinking water chemistry, pesticides and herbicides and the etiology of Parkinson's disease.

In 1984 we made the first observation of a correlation between early age exposure to rural environment (and drinking well water) and development of idiopathic Parkinson's disease (IPD). These findings were subsequently confirmed elsewhere (Barbeau, 1985;25 Tanner, 1985). Analysis of all early age onset IPD (EPD) cases born and raised in Saskatchewan revealed that 20 of 22 had exclusively rural exposure during the first 15 years of life. This distribution was significantly different from the general population (p = 0.0141). Further study of the EPD group included sampling and metal analysis of childhood sources of drinking water in 18 cases and 36 age and sex-matched controls. Water collected from the two groups was analyzed for 23 metals (including 7 elements implicated in the etiology of IPD). There was no difference in the metal composition of the water between the two groups. Finally, a review of herbicide and pesticide use in Saskatchewan agriculture was undertaken to determine if there was an increased incidence of EPD following utilization of any particular chemical. No increase was found in the incidence of EPD with the introduction of any pesticide or herbicide, including Paraquat, for agricultural use. We conclude that there is a strong correlation between early age rural environmental exposure and development of IPD. We believe well water is a likely vehicle for the causal agent, but neither water metal concentration nor any of the herbicides and pesticides used in Saskatchewan agriculture are related to the cause.

Adult↗
PubMed1987

Regional distribution of metals in human brain.

Progress in understanding the role of metals in diseases of the nervous system has been hampered to a large extent by a lack of normal metal concentration values in the human brain. Since several metals interact metabolically, concurrent metal levels are essential for clinical correlation. We are reporting a simultaneous analysis of 24 metals in 4 different areas of 9 human brains. Our data on previously studied metals are comparable to the past observations. Therefore, we suggest the values of all metals reported here should be regarded as "normal" for ages 58-78 years.

Aged↗
PubMedDate not supplied

Transcatheter arterial chemoembolization in inoperable hepatocellular carcinoma: four-year follow-up.

PURPOSE: To evaluate the efficacy of repeated chemoembolization in patients with inoperable hepatocellular carcinoma (HCC). PATIENTS AND METHODS: One hundred thirty-two patients with HCC underwent transcatheter arterial chemoembolization with an emulsion of iodized oil and cisplatin. In 104 patients, "light" gelatin sponge embolization was also used. Chemoembolization was repeated every 1.5-3.0 months in most patients (range, one to 18 chemoembolization sessions). RESULTS: In 74 patients, the HCCs became smaller or disappeared after chemoembolization. Decreases in size were seen in 55 of 76 HCCs 9 cm or smaller, 17 of 42 HCCs between 9 and 18 cm, and two of 14 HCCs larger than 18 cm. Use of gelatin sponge pledgets enhanced the response in tumors larger than 9 cm. Seven of 74 HCCs that responded to chemoembolization increased in size later. New daughter nodules that appeared at other sites responded to chemoembolization in 24 of 40 patients. Further new nodules appeared in 14 of 24 patients, and in six patients they responded to therapy. Median survival was 26 months for patients with responsive HCCs and 5 months for those with unresponsive lesions. CONCLUSION: Tumor size at the start of chemoembolization influenced the response to treatment and survival. The addition of gelatin sponge improved results only in tumors larger than 9 cm. Recurrence after an initial response was due more to the appearance of new daughter nodules in new locations rather than recrudescence of the presenting tumor.

Adolescent↗
PubMedDate not supplied

Hemoperitoneum caused by spontaneous rupture of a true splenic cyst.

A 34 year-old man presented with hemoperitoneum from a spontaneously ruptured spleen. At laparotomy, a 5-cm diameter splenic cyst was found to be ruptured. Histological examination confirmed the diagnosis of a true splenic cyst of the mesothelial type. Spontaneous rupture with hemoperitoneum is a rare but potentially lethal complication of a true splenic cyst.

Adult↗