Ganglion atrial natriuretic peptide in NaCl sensitive spontaneously hypertensive rats

Reports from other laboratories have shown that atrial natriuretic peptide (ANP) stores in sympathetic ganglia are increased during dietary NaCl supplementation in normotensive rats. We have previously demonstrated that dietary NaCl supplementation in NaCl sensitive spontaneously hypertensive rats (SHR-S) exacerbates hypertension and enhances peripheral sympathetic nervous system activity, while NaCl resistant Wistar-Kyoto (WKY) rats show neither response. Since endogenous ANP may inhibit ganglion transmission, an inability of SHR-S to increase ganglion ANP appropriately in response to high NaCl feeding could contribute to the NaCl induced increase in sympathetic nervous system activity and blood pressure in this model, while an increase in ganglion ANP in NaCl supplemented WKY would tend to prevent sympathetic activity and blood pressure from rising. The current study tested the hypothesis that ganglion ANP levels increase in WKY but not in SHR-S during dietary NaCl supplementation. Male SHR-S and WKY rats were placed on 1% or 8% NaCl diets at 7 weeks of age. The rats were decapitated without prior anesthesia 3 weeks later, and the superior cervical and celiac ganglia were removed for the measurement of ANP by radioimmunoassay. Dietary NaCl supplementation produced significant increases in blood pressure in SHR-S, but not in WKY rats; the high NaCl diet was associated with significant increases in the ANP content of superior cervical and celiac ganglia in WKY rats, but not in SHR-S.(ABSTRACT TRUNCATED AT 250 WORDS)

Extracorporeal liver ablation using sonography-guided high-intensity focused ultrasound

RATIONALE AND OBJECTIVES

High-intensity focused ultrasound (HIFU) is the only radiation beam that can remotely destroy deep-seated tissue targets without causing damage to the intervening tissues. This study evaluates the ability of sonography-guided HIFU to extracorporeally induce liver ablation in a rabbit model.

METHODS

Under sonographic guidance, the HIFU beam was transcutaneously focused at the target tissue in the liver through a subcostal approach. A computer controlled the HIFU exposure and transducer movement to destroy a preselected tissue volume. Simultaneous sonography monitored the tissue response. Ten insonated rabbits were killed from days 0 to 10, and the liver and intervening tissues were examined histologically.

RESULTS

A sharply demarcated sonolesion of coagulation necrosis was produced in the liver in 9 of 10 animals. No damage was found in the intervening tissues (n = 6) when adequate acoustic coupling and proper beam path was applied.

CONCLUSION

Sonography-guided HIFU might be a potential new modality for extracorporeal inducement of liver cancer ablation without resorting to laparatomy.

Novel method to extract large amounts of bacteriocins from lactic acid bacteria

Antimicrobial peptides, bacteriocins, produced by lactic acid bacteria were adsorbed on the cells of producing strains and other gram-positive bacteria. pH was a crucial factor in determining the degree of adsorption of these peptides onto cell surfaces. In general, between 93 and 100% of the bacteriocin molecules were adsorbed at pHs near 6.0, and the lowest (< or = 5%) adsorption took place at pH 1.5 to 2.0. On the basis of this property, a novel isolation method was developed for bacteriocins from four genera of lactic acid bacteria. By using this method we made preparations of pediocin AcH, nisin, sakacin A, and leuconocin Lcm1 that were potent and concentrated. This method produced a higher yield than isolation procedures, which rely on precipitation of the bacteriocins from the cell-free culture liquor. It is simple and can be used to produce large quantities of bacteriocins from lactic acid bacteria to be used as food biopreservatives.

Effects of amino-terminal extensions and specific mutations on the activity of restrictocin

The cytotoxic activities of restrictocin with aminoterminal extensions and specific mutations were investigated using in vivo and in vitro systems. Genes were constructed from the cDNA clone of restrictocin which encode: the native form of restrictocin (including the leader sequence); Met-prorestrictocin, in which a codon for methionine was placed before a putative pro region; Met-mature restrictocin, with a methionine codon prior to the mature form of restrictocin; and three mutated forms of Met-mature restrictocin, E95G, E115G/H136L, and H136L. These constructions were placed under the control of the GAL1 promoter and were transformed into Saccharomyces cerevisiae. Transformants were killed, and a new RNA band formed when any of these genes except those containing the H136L mutation were expressed. Restrictocin protein was detected by immunoblot only in cells expressing the native form of restrictocin and the forms containing the H136L mutation. Native restrictocin, Met-prorestrictocin, and Met-mature restrictocin mRNA were translated in an in vitro system resulting in proteins of the expected molecular weight and inactivation of the translation system. Restrictocin was not inactivated by the presence of the leader sequence and the putative prosequence. Amino acid His136 is putatively in the active site of restrictocin by analogy to ribonuclease U2 and the elimination of toxic effects in the S. cerevisiae expression and in vitro translation systems.

[A research on the quality of radix Astragali]

Milkvetch root (Radix Astragali) and its likes were determined in their contents of trace elements, total extracts and astragalin A. The result showed there was some relationship between the drug quality, trace-element contents, difference of species, growing areas and on-the-spot processing methods.

Salt supplementation does not alter the pressor effect of blocking atrial natriuretic peptide in nucleus tractus solitarii

We have previously shown that microinjection of monoclonal antibody to atrial natriuretic peptide (ANP) into the caudal nucleus tractus solitarii causes a pressor response in salt-sensitive spontaneously hypertensive rats (SHR) fed a basal (1%) salt diet, suggesting that endogenous ANP in this region may be involved in the centrally mediated regulation of blood pressure in this model. The present study tested the hypothesis that the pressor effect of blocking endogenous ANP in caudal nucleus tractus solitarii is enhanced by dietary salt supplementation in salt-sensitive SHR. Monoclonal antibody to ANP (0.55 micrograms) in 50 nl artificial cerebrospinal fluid or control immunoglobulin G was microinjected into the caudal nucleus tractus solitarii of conscious salt-sensitive SHR, salt-resistant SHR, and Wistar-Kyoto rats fed 1% or 8% salt diets for 3 weeks. Microinjection of the monoclonal antibody into the caudal nucleus tractus solitarii evoked similar increases in mean arterial pressure in salt-sensitive SHR on both 1% and 8% salt diets and in salt-resistant SHR on a 1% salt diet but had no effect in Wistar-Kyoto rats. In contrast, microinjection of control immunoglobulin G into this brain area did not alter mean arterial pressure or heart rate in any experimental group. Thus, endogenous ANP in caudal nucleus tractus solitarii mediates tonic control of blood pressure in both salt-sensitive and salt-resistant SHR but not in Wistar-Kyoto rats, and this effect is independent of the salt sensitivity of hypertension and of dietary salt intake.

Regulation of restrictocin production in Aspergillus restrictus

The production of restrictocin (a cytotoxin that specifically cleaves ribosomal RNA) by cultures of Aspergillus restrictus grown in liquid medium was investigated. The function of restrictocin, the method of its accumulation and the mode of resistance to restrictocin in A. restrictus are unknown. Previous studies have indicated that restrictocin accumulates in the medium with culture age. These observations have been extended in this study by cloning the cDNA of the res gene and using this cDNA clone to probe the onset of messenger RNA synthesis in the cells. The results of the Northern analysis were compared to the production and accumulation of restrictocin and morphological differentiation of the cells in culture. Restrictocin was found in the medium at the same time that mRNA was detected in the cells. This suggests that the leader sequence encoded by the cDNA provides an efficient secretion system for the protein. Both the protein and the mRNA were detected coincident with the formation of differentiated cell structures. These structures develop into conidiophores with one layer of sterigmata and conidia forming from the sterigmata. These results suggest that restrictocin is either involved in the process of conidiation or is coordinately regulated with differentiation leading to conidiation.

Effects of acute and chronic blockade of neutral endopeptidase with Sch 34826 on NaCl-sensitive hypertension in spontaneously hypertensive rats

We have previously demonstrated that dietary NaCl supplementation is associated with increased circulating atrial natriuretic peptide (ANP) levels in Wistar-Kyoto (WKY) rats but not in spontaneously hypertensive rats (SHR), and that replacement with exogenous ANP prevents NaCl-sensitive hypertension in NaCl-sensitive SHR (SHR-S). The current study tested the hypothesis that chronic administration of the neutral endopeptidase (NEP) inhibitor Sch 34826 prevents NaCl sensitive hypertension in SHR-S by increasing endogenous ANP. Male SHR-S received Sch 34826 (90 mg/kg/day) or vehicle by gavage for 4 weeks beginning immediately before the initiation of 1% or 8% NaCl diets at age 7 weeks. Sch 34826 prevented the increase in arterial pressure in response to 8% NaCl in SHR-S, but had no effect on blood pressure in 1% NaCl fed SHR-S; plasma ANP levels were increased by 63 and 68% in the 1% and 8% NaCl groups, respectively, in response to Sch 34826. To examine the mechanism(s) of the antihypertensive effect of Sch 34826 in NaCl-supplemented SHR-S, a single dose (90 mg/kg) of Sch 34826 or vehicle was administered by gavage to SHR-S that had consumed 1% or 8% NaCl diets for 3 weeks. Sch 34826 abolished the NaCl-induced increase in blood pressure 3 h after treatment in 8% NaCl fed SHR-S, but had no effect in SHR-S fed the 1% NaCl diet. This effect was associated with increased urine volume and urinary sodium, ANP, and cyclic GMP in 8% NaCl fed SHR-S.(ABSTRACT TRUNCATED AT 250 WORDS)

A reproducible rat liver cancer model for experimental therapy: introducing a technique of intrahepatic tumor implantation

To investigate therapeutic strategies for hepatoma, it is necessary to have a reproducible animal model with a tumor growth pattern allowing accurate assessment of results. Many techniques of intrahepatic tumor implantation (IHTI) have been devised for intrahepatic tumor models. Most of them, however, have the disadvantage of high rates of artificial tumor dissemination during tumor implantation, which interferes with the evaluation of therapy. To overcome this problem, we have developed a technique of IHTI in which a piece of Gelfoam is placed into a small incision in the liver for the purpose of both hemostasis and formation of a tension-free pocket to accept the tumor implant. In 583 ACI rats receiving IHTI with Morris hepatoma 3924A, the tumor take rate was 100%. Resembling the natural course of human hepatoma, the implanted tumor grows locally early in the course of disease and eventually invades the surrounding organs causing ascites and also metastasizes to the lung. Liver microangiography demonstrated that the tumor received blood supply mainly from the hepatic artery. This IHTI technique was also compared to two other methods of IHTI: insertion of fragments without using Gelfoam and implantation with a tumor cell suspension. A significantly lower rate of early lung metastases was achieved with our technique (0%) in comparison with other two techniques (41 and 80%). We conclude that this rat liver cancer model is reproducible and allows efficient evaluation of treatment modalities for liver cancer without interference from tumor at undesirable sites.

A reproducible rat liver cancer model for experimental therapy: introducing a technique of intrahepatic tumor implantation

To investigate therapeutic strategies for hepatoma, it is necessary to have a reproducible animal model with a tumor growth pattern allowing accurate assessment of results. Many techniques of intrahepatic tumor implantation (IHTI) have been devised for intrahepatic tumor models. Most of them, however, have the disadvantage of high rates of artificial tumor dissemination during tumor implantation, which interferes with the evaluation of therapy. To overcome this problem, we have developed a technique of IHTI in which a piece of Gelfoam is placed into a small incision in the liver for the purpose of both hemostasis and formation of a tension-free pocket to accept the tumor implant. In 583 ACI rats receiving IHTI with Morris hepatoma 3924A, the tumor take rate was 100%. Resembling the natural course of human hepatoma, the implanted tumor grows locally early in the course of disease and eventually invades the surrounding organs causing ascites and also metastasizes to the lung. Liver microangiography demonstrated that the tumor received blood supply mainly from the hepatic artery. This IHTI technique was also compared to two other methods of IHTI: insertion of fragments without using Gelfoam and implantation with a tumor cell suspension. A significantly lower rate of early lung metastases was achieved with our technique (0%) in comparison with other two techniques (41 and 80%). We conclude that this rat liver cancer model is reproducible and allows efficient evaluation of treatment modalities for liver cancer without interference from tumor at undesirable sites.

Effects of high-intensity focused ultrasound in the treatment of experimental neuroblastoma

This report evaluates the effect of high-intensity focused ultrasound (HIFU) on subcutaneous murine neuroblastoma C1300. HIFU treatment was administered with a focused 4-MHz quartz transducer with a peak intensity of 550 W/cm2. In experiment 1, 60 animals with tumor were divided into four groups. Group I (n = 15) were controls; group II (n = 15) received adriamycin, 5 mg/kg intraperitoneally; group III (n = 15) received HIFU; and group IV (n = 15) received both adriamycin and HIFU. All the animals in groups I and II died of tumor by 35 days. Fifty-three percent (8/15) of mice in group III and 80% (12/15) in group IV were cured with no evidence of tumor (NET) at 200 days. Log-rank statistics showed significant prolongation of survival in the groups III and IV as compared with groups I or II (P less than .05). In experiment 2, 45 animals with tumor were divided into three groups. Group I (n = 15) were controls; group II (n = 15) received HIFU; and group III (n = 15) received repeated HIFU. The results showed 47% (7/15) of mice in group II and 67% (10/15) in group III were NET at 200 days. Significant survival prolongation was achieved in groups II and III in comparison with group I (P less than .05). In experiment 3, 90 mice received either tumor (n = 60) or saline (n = 30) inoculation in the left flank. On day 5, 45 mice with tumor were treated with HIFU (group I), while the other 15 mice with tumor (group II) had a sham procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatic artery ligation and infusion chemotherapy for unresectable primary liver cancer

During the period of 1958-1989, 356 patients with pathologically proven primary liver cancer (PLC) were determined by laparotomy to be unresectable. Of the 356 patients, 51 (14.3%) were of subclinical stage, 287 (80.6%) of moderate stage and 18 (5.1%) of late stage. The association of liver cirrhosis was present in 310 patients (87.1%). Treatment modalities in 356 patients were divided into 4 groups: hepatic artery ligation (HAL) (51), hepatic artery infusion (HAI) of chemotherapeutic agents (114), HAL + HAI (117), and HAL + HAI + radiotherapy (74). The 5-year survival rate was zero in the 4 groups in the period of 1958-1977. During 1978-1989, however, the 5-year survival rate was zero in HAL, 7.9% in HAI, 24.4% in HAL + HAI (with second look resection in 10 patients), and 36.5% in HAL + HAI + radiotherapy (with second look resection in 19). The marked improvement in survival in later period was attributable to the accurate site of hepatic artery catheter, longer infusion chemotherapy, and combination treatment, particularly second look resection in some of the patients. These results indicate that HAL + HAI + combination treatment might provide a possible prolongation of survival or even resection in some patients with original unresectable PLC.

High-intensity focused ultrasound in the treatment of experimental liver cancer

High-intensity focused ultrasound (HIFU) was used to treat Morris rat hepatoma 3924A implanted in the liver. Treatment was administered with a lens-focused 4-MHz transducer that created a focused beam of 550 W/cm2 at peak intensity. One hundred twelve rats with liver tumors were divided into two groups of 56 each. Group 1 received HIFU therapy while group 2 (the control group) did not. All rats were killed immediately or 1, 3, 7, 14, 21, or 28 days after treatment. Eight rats in each group were killed at each interval for pathologic and biochemical studies. Significant inhibition of the tumor growth was seen in the HIFU-treated group, with tumor growth inhibition rates of 65.4% to 93.1% from the third to the 28th day after treatment. Ultrasound-treated tumors showed direct thermal cytotoxic necrosis and fibrosis. An additional 56 ACl rats with liver tumors were divided into four groups of 14 each. Group 1 received doxorubicin hydrochloride intraperitoneally and HIFU therapy; group 2, HIFU therapy; group 3, doxorubicin hydrochloride; and group 4 (the control group), neither HIFU nor doxorubicin hydrochloride. Significantly improved survival rates were noted in HIFU-treated animals (groups 1 and 2) compared with those of groups 3 and 4. These data suggest that HIFU may be a useful method for local treatment of hepatic tumors.

Impaired hepatic bacterial clearance is reversed by surgical relief of obstructive jaundice

Sepsis is a major cause of morbidity and mortality in infants with cholestatic jaundice. Previous studies have shown that biliary obstruction in rats causes a significant decrease in hepatic phagocytosis of viable Escherichia coli. This study tests this hypothesis and further evaluates whether the impaired function of the reticuloendothelial system of the liver (Kupffer cells) can be reversed by the relief of the biliary obstruction. Male Sprague-Dawley rats (weighing 140 to 150 g) were placed in three groups. Group I (n = 10) consisted of sham-operated controls. In Group II (n = 30), ligation and division of distal common bile duct (CDL) was performed. Group III (n = 30) underwent choledochoduodenostomy 2 weeks following ligation and division of common bile duct. At 1, 2, and 3 weeks following the operation, 10(9) 35S-radiolabeled viable E coli were injected intravenously via the tail vein. At 10 minutes, bacterial distribution in the liver, spleen, kidneys, and lungs was determined. Tissue samples (50 to 100 mg) from each organ were processed for liquid scintillation counting. The final distribution of bacteria was calculated from the input specific activity (dpm/bacteria) and expressed as the mean percentage of injected viable E coli per gram of tissue and per total organ weight. There was a significant decrease in the trapping of bacteria by the liver's Kupffer cells in rats in group II, at 2 and 3 weeks following CDL (45.0% +/- 14.0% and 15.1% +/- 4.9%, respectively, v controls 75.9% +/- 13.7%; P less than .005).(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinogenesis studies in rodents for evaluating risks associated with chemical carcinogens in aquatic food animals

Fish and shellfish caught in polluted waters contain potentially dangerous amounts of toxic and carcinogenic chemicals. Public concern was heightened when a large percentage of winter flounder taken from Boston Harbor was found to have visible cancer of the liver; winter flounder outside the estuary area had no liver lesions. Long-term chemical carcinogenesis studies could be easily and feasibly designed using laboratory rodents offered diets containing fish caught in polluted waters. Induced cancers in rodents would corroborate field observations in fish; positive results from these studies would provide further evidence about potential human health hazards from eating substantial amounts of chemically contaminated fish. Nonetheless, fish and aquatic organisms should be viewed as environmental biological monitors of pollution or of potential human health hazards, and authorities responsible for assuring clean and safe rivers, bodies of water, and biota should give more attention to these valid biological indicators or sentinels of environmental pollution. Consequently, fish and other sea creatures alone should serve as alarms regarding whether water areas constitute public health hazards.

Direct visualization of phosphorylase-phosphorylase kinase complexes by scanning tunneling and atomic force microscopy

In skeletal muscle the activation of phosphorylase b is catalyzed by phosphorylase kinase. Both enzymes occur in vivo as part of a multienzyme complex. The two enzymes have been imaged by atomic force microscopy and the results compared to those previously found by scanning tunneling microscopy. Scanning tunneling microscopy and atomic force microscopy have been used to view complexes between the activating enzyme phosphorylase kinase and its substrate phosphorylase b. Changes in the size and shape of phosphorylase kinase were observed when it bound phosphorylase b.

Scanning tunneling microscopic images show a laminated structure for glycogen molecules

Scanning tunneling microscopy (STM) has been used to examine glycogen molecules. Individual molecules were approximately ellipsoidal with dimensions in the 20- to 60-nm range. Images of the glycogen molecular surfaces have a laminar appearance. The layered features seen on the surfaces of the molecules suggest that glycogen may grow from one edge as a laminar structure to form an ellipsoid rather than originating at a central point with radial growth of the oligosaccharide chains to form a sphere. The results of these studies indicate that STM can be used to determine details of polysaccharide structures.

Scanning tunneling microscopy of the enzymes of muscle glycogenolysis

Scanning tunneling microscopy (STM) has been used to examine the structures of the skeletal muscle enzymes phosphorylase and phosphorylase kinase. The interaction of these two proteins represents the last step in the process of signal transduction which results in muscle glycogen being converted into metabolic energy for use in muscle contraction. Phosphorylase b has a molecular weight of 97,000 and the dimer is seen by STM to have dimensions of 11 X 5.7 nm. Phosphorylase b has a tendency to form linear arrays of dimers on the graphite surface used as the support for STM imaging. Phosphorylase kinase is imaged as a butterfly-like object with lateral dimensions of 36 X 27 nm. The molecular thicknesses given by scanning tunneling microscopy for these two non-conducting molecules is significantly less than expected. The height measurement in STM is dependent not only on the surface topology of the object being imaged, but also on the electronic work function of the object compared to that of the graphite surface on which it lies. In addition to the individual proteins, a complex between phosphorylase and phosphorylase kinase has been observed by scanning tunneling microscopy.

Adequacy of disposable biopsy forceps for gastrointestinal endoscopy: a direct comparison with reusable forceps

Disposable plastic biopsy forceps were compared prospectively to reusable stainless steel forceps. Thirty consecutive patients underwent a total of 249 biopsies, 124 with the disposable forceps, and 125 with reusable forceps. Biopsy locations included the esophagus, stomach, small intestine, colon, and common bile duct. Specimens were compared microscopically to determine overall surface area, depth, adequacy, and diagnostic result. The disposable biopsy forceps yielded specimens which were 37% smaller when compared with the reusable forceps. In five of the comparisons, minor differences in histological findings were noted between the two groups of biopsy specimens, but these differences did not alter the pathological diagnosis. However, in three cases in which superficial specimens were obtained, an underlying carcinoma was missed with the disposable forceps. Our study documents the utility of disposable biopsy forceps for mucosal lesions. In addition, there were 11 mechanical failures in 38 biopsy attempts with the plastic biopsy forceps. These forceps appear to be limited in their capacity to obtain adequate specimens from firm tissue or when submucosal biopsy samples are required, and they will require refinements in design to duplicate specimen quality obtained by traditional reusable forceps. Disposable forceps are particularly suitable for biopsy of mucosal lesions in patients with possible communicable disease, and they should help to reduce cross-contamination in the gastroenterology laboratory.

[Clinical analysis of 418 patients with Wilson's disease in traditional Chinese medicine and Western medicine therapy]

From 1974 to 1988, 418 cases of Wilson's disease were treated with TCM-WM in our hospital. 147 cases were of Wilson's type; 149 cases were of pseudosclerosis type; 40 cases were of abdominal and hepatocerebral type; 21 cases were of choreoathetosis type and 21 cases of other types. After a course of treatment for 3 to 6 months, 103 patients showed marked improvement and 286 made some improvement, but no effect was found in 22 patients and 7 deaths were observed. The results were as follows: (1) The mortality in the severe and moderate groups were significantly higher than the mild (P less than 0.05) and the marked effective rate was less than the latter (P less than 0.01). (2) The marked effective rate was lower in abdominal and hepatocerebral type, and no significant difference was found in recovery rate between Wilson's type and pseudosclerosis type.

Radioimmunotherapy in the multimodality treatment of hepatocellular carcinoma with reference to second-look resection

Experimental study using nude mice human hepatocellular carcinoma (HCC) xenograft indicated that the combination treatment with iodine 131 (131I)-anti-human HCC isoferritin (131I-isoFtAb), cisplatin, and mixed bacterial vaccine (MBV) yielded better inhibition rate as compared with double combination or 131I-isoFtAb alone. Based on these findings, 25 patients with surgically proven nonresectable and pathologically proven HCC have been treated by radioimmunotherapy using 131I-isoFtAb intrahepatic arterial infusion as a part of multimodality treatment. Of the 25 patients, seven (28.0%) received second-look resection after marked shrinkage of tumor. The 1-year survival was 52.5% (12/23) and 2-year survival 27.7% (five of 18) in the entire series. Of the five patients with 2-year survival, four were in the second-look resection group. Patients with tumor less than or equal to 8 cm showed higher second-look resection rate (62.5% versus 11.8%) and 1-year survival (85.7% versus 37.5%) as compared with tumor greater than 8 cm. Mixed bacterial vaccine as adjuvant immunotherapy seemed effective to prolong survival. The 2-year survival was higher in patients with second-look resection as compared with those without (75.0% versus 14.3%). Thus, radioimmunotherapy using 131I-isoFtAb might be one of the modalities of choice, particularly in the conversion of nonresectable to resectable HCC in a well-designed multimodality treatment regimen.

Surgery of small hepatocellular carcinoma. Analysis of 144 cases

A long-term follow-up study of 144 cases with surgically and pathologically proved small hepatocellular carcinoma (less than or equal to 5 cm) from 1967 to 1987 is reported. One hundred eight cases (75.0%) were detected by alpha-fetoprotein serosurvey and/or ultrasonography mainly in a high-risk population; 129 cases (89.6%) coexisted with cirrhosis. Resection was done in 132 cases (91.7%) with three (2.3%) operative deaths; cryosurgery, laser vaporization, and hepatic arterial chemotherapy were used in the rest. Limited resection was done in 67.4% of resections. Reresection of subclinical recurrence or solitary pulmonary metastasis was done in 21 cases. The 5-year and 10-year survival rates were 67.9% and 53.4% in the resection group but zero in the nonresection group. Survival was correlated negatively with tumor size, 5-year survival after resection was 84.6% in tumors less than or equal to 2 cm but 59.5% in tumors of 4.1 to 5 cm. The increase of resectability and reresection resulted in marked improved of 5-year survival from 43.5% in 1973 to 1977 to 63.3% in 1978 to 1982 in the entire series. No significant difference was found between survival of limited resection and lobectomy. Resection may be the modality of choice for treatment of small hepatocellular carcinomas with compensated liver function. Limited resection instead of lobectomy was the key to increased resectability and decreased operative mortality in cirrhotic livers. Reresection of subclinical recurrence was important to prolong survival further.

Surgery of small hepatocellular carcinoma. Analysis of 144 cases

A long-term follow-up study of 144 cases with surgically and pathologically proved small hepatocellular carcinoma (less than or equal to 5 cm) from 1967 to 1987 is reported. One hundred eight cases (75.0%) were detected by alpha-fetoprotein serosurvey and/or ultrasonography mainly in a high-risk population; 129 cases (89.6%) coexisted with cirrhosis. Resection was done in 132 cases (91.7%) with three (2.3%) operative deaths; cryosurgery, laser vaporization, and hepatic arterial chemotherapy were used in the rest. Limited resection was done in 67.4% of resections. Reresection of subclinical recurrence or solitary pulmonary metastasis was done in 21 cases. The 5-year and 10-year survival rates were 67.9% and 53.4% in the resection group but zero in the nonresection group. Survival was correlated negatively with tumor size, 5-year survival after resection was 84.6% in tumors less than or equal to 2 cm but 59.5% in tumors of 4.1 to 5 cm. The increase of resectability and reresection resulted in marked improved of 5-year survival from 43.5% in 1973 to 1977 to 63.3% in 1978 to 1982 in the entire series. No significant difference was found between survival of limited resection and lobectomy. Resection may be the modality of choice for treatment of small hepatocellular carcinomas with compensated liver function. Limited resection instead of lobectomy was the key to increased resectability and decreased operative mortality in cirrhotic livers. Reresection of subclinical recurrence was important to prolong survival further.