[Augmented antitumor efficacy of combination chemotherapy of nedaplatin with 5-fluorouracil in in vivo murine and human tumor model]

Augmented antitumor activity was demonstrated in combination chemotherapy of Nedaplatin (NDP) or Cisplatin (CDDP) with 5-fluorouracil (5-FU) against murine lung carcinoma and human squamous carcinoma from head and neck. Either NDP or CDDP (1/4 to 1 maximum tolerated dose; MTD) was injected once and 5-FU (1/16 MTD) was injected daily for five days via tail vein to tumor-implanted mice. The sequential administration of either NDP or CDDP prior to 5-FU (NF or CF therapy) showed severe body weight loss followed by the toxic death of tumor-bearing mice at the MTD of NDP or CDDP. In contrast, the reverse sequence of the treatment, that is, 5-FU prior to NDP or CDDP (FN or FC therapy), resulted in the synergistically enhanced inhibition of tumor growth and the prolonged survival in comparison with NDP, CDDP or 5-FU monotherapy. The antitumor activities of the combinations of CDDP with 5-FU was less than those of the combination of NDP with 5-FU. Especially, at the MTD of NDP in FN therapy, long-term tumor-free survival was frequently observed. Thus, FN therapy was thought to be the most efficient regimen in combination of NDP with 5-FU as a clinical therapy.

PKC and tyrosine kinase involvement in amyloid beta (25-35)-induced chemotaxis of microglia

Microglia are activated by amyloid beta (Abeta) in vivo and in vitro, and Abeta-activated microglia may be involved in the pathogenesis of Alzheimer's disease (AD). We investigated the mechanism of microglial chemotaxis induced by Abeta (25-35), an active fragment of Abeta. Abeta (25-35) 0.1 and 1 nM stimulated microglial chemotaxis. The protein kinase C (PKC) inhibitors chelerythrine (0.5 and 2 microM), calphostin C (1 microM) and staurospine (10 nM) significantly inhibited the microglial chemotaxis induced by Abeta (25-35) (1 nM). The chemotactic effect of Abeta (25-35) on microglia was desensitized by pretreatment of microglia with 1 ng/ml 12-O-tetradecanoylphorbol 13-acetate (TPA). Pretreatment of cells with Abeta (25-35) (1 nM) also desensitized the chemotactic effect by Abeta (25-35) (1 nM). The desensitization by TPA or Abeta (25-35) was inhibited when staurosporine was present in the pretreatment media. The tyrosine kinase inhibitor herbimycin A (0.1 and 1 microM) significantly inhibited the microglial chemotaxis induced by Abeta (25-35) (1 nM). Based on these observations, it seems likely that PKC and tyrosine kinase are involved in the Abeta-induced chemotaxis of microglia.

Sequence-dependent antitumour efficacy of combination chemotherapy of nedaplatin, a novel platinum complex, with 5-fluorouracil in an in vivo murine tumour model

The antitumour efficacy of a sequential combination of nedaplatin (NDP) and 5-fluorouracil (5-FU) was evaluated using Lewis lung carcinoma in vivo. NDP was developed as a second generation platinum complex. Because it has greater antitumour activity and lower nephrotoxicity than cisplatin (CDDP), we also compared the antitumour activity of NDP plus 5-FU with that of CDDP plus 5-FU. A fixed 5-FU dose was injected daily for 5 days and increasing doses of either NDP or CDDP were injected once via the tail vein into the Lewis lung carcinoma-implanted mice. The sequential administration of either NDP or CDDP prior to 5-FU (NF or CF therapy) resulted in severe body weight loss followed by the death of the tumour-bearing mice when the high-dose of NDP or CDDP was administered. In contrast, the sequential administration of 5-FU prior to NDP or CDDP (FN or FC therapy) resulted in synergistically enhanced inhibition of tumour growth and prolonged survival in comparison with NDP, CDDP or 5-FU monotherapy. At the high-dose of NDP in FN therapy, a reduction of tumour size and long-term tumour-free survival were frequently observed. The survival effect of the combinations of NDP with 5-FU was superior to those of the combination of CDDP with 5-FU. In conclusion, the sequence-dependent antitumour efficacy and toxicity of the combination of NDP or CDDP with 5-FU was demonstrated in this study, and FN therapy appeared to be the most efficient regimen as a clinical therapy.

A rare case of primary malignant mesothelioma originating from the rectovaginal tissue

A 35 year-old female patient with pelvic malignant mesothelioma is described. The patient underwent total pelvic exenteration due to a pelvic tumor. Macroscopically, the resected tumor was located in the rectovaginal lesion with invasion into the rectal and vaginal wall, and around the internal urethral ostium. Light microscopically, the tumor predominantly consisted of sheets of plump round cells with acidophilic cytoplasm, and focally of tumor cells showing papillary growth pattern. The tumor cells showed remarkable cellular pleomorphism, and were both alcian blue and periodic acid-Schiff stain negative. Electron microscopically, these tumor cells had numerous long bush-like microvilli on their surface with increased length/width ratios. Positive staining with epithelial membrane antigen, cytokeratin, and vimentin, and negative staining with the carcinoembryonic antigen and S-100 protein were observed immunohistochemically. Based on these histological and immunohistochemical estimations, the tumor was diagnosed as a primary malignant mesothelioma originating from the rectovaginal tissue. Review of the literature confirmed the rarity of pelvic malignant mesothelioma. The possibilities of the pathogenesis of the tumor include the tumor's arising from the peritoneal remnant in the rectovaginal tissues, or from the epithelium of the secondary Mullerian system, which shares the same ancestry with the peritoneum.

[Treatment strategy for cancer of the colorectum--difference with western approach]

In Japan, extensive radical surgery is used for advanced cancer, whereas in western countries the standard operative approach used in Japan 20-30 years ago is used, followed by rather aggressive adjuvant therapy-chemotherapy and irradiation therapy by medical oncologists. The results of the extensive radical operations performed in Japan, called the "Japanese operation," have drawn attention but hesitate to undertake for a big aggression; instead the TME proposed by Heald is gaining ground, although we don't appreciate it. In Japan, more and more cases are being discovered relatively early, and function preserve operations to preserve pelvic nerves, or EMR (endoscopic mucous resection) have been developed and are seeing progressively widespread application. Therapeutic results have been considered to have remained unchanged in the past 20-30 years in western nations, whereas they have much improved in Japan, mainly because of relatively earlier discovery in an increased number of cases and the progress in surgical techniques.

Anticancer efficacy in vivo and in vitro, synergy with 5-fluorouracil, and safety of recombinant methioninase

The elevated exogenous-methionine dependency of tumors for growth has been observed in all major cancer cell types. We have previously cloned a methioninase (rMETase) from Pseudomonas putida to deplete methionine. Growth inhibition followed by apoptotic cell death was induced by treatment of tumor cells with rMETase in vitro. A single i.p. injection of 300 units of rMETase can lower the serum methionine level in the mice from 70 microM to less than 1 microM within 2 h and maintain this depleted level for 8 h. Repeated dosing of rMETase of tumor-bearing mice could be administered without acute immune-hypersensitivity. rMETase treatment demonstrated growth inhibitory activity against human tumors in nude mice, including those which were multiple drug-resistant. No body weight loss or hematotoxicity, except a slight anemia, was found throughout the therapy. The combined treatment of the Lewis lung carcinoma with a fixed rMETase dose and increasing doses of 5-fluorouracil (5-FU) resulted in a dose-dependent enhanced antitumor efficacy for survival as well as tumor growth inhibition. Thus, methionine depletion by rMETase potentiates the antitumor efficacy of 5-FU. The data presented in this report thus indicate that rMETase is active alone, is synergistic in combination with 5-FU, and has negligible toxicity suggesting a novel clinical approach for effective cancer therapy.

[Chemotherapy of gastric cancer]

At present curative resection is the only radical treatment for gastric cancer, although recently developed combination chemotherapy shows increased activity in treating locally advanced and metastatic disease. Among several combination regimens, those based on biochemical modulation, such as sequential methotrexate/5-fluorouracil or low-dose CDDP/5-fluorouracil, are thought to provide increased efficacy with decreasing adverse reactions in unresectable gastric cancer. Therefore, a prospective randomized clinical trial comparing the prognosis of patients receiving adjuvant multi-agent chemotherapy with those treated only surgically should be pursued for estimation of the clinical benefit of these agents.

[Chemoradiation therapy for esophageal carcinoma]

Cancer of the esophagus poses a great challenge to the surgical, medical, and radiation professions. Despite standardization of resection and reconstruction techniques, extended lymph node dissection, and advances in perioperative management, the overall prognosis of patients with esophageal cancer undergoing surgical resection has not improved. Preoperative combination chemoradiation therapy in patients with squamous cell esophageal carcinoma has recently received increasing attention, because preoperative chemoradiation therapy, consisting of the concurrent combination of 5-fluorouracil, cis-platinum and radiation, appears to increase the resection rate, the rate of pathological complete responders, and survival time after esophagectomy in patients with locally advanced tumors. Overall in the trials using preoperative concurrent chemoradiotherapy, major antitumor responses have been reported in 40% to 80% of patients, and, consistently, up to 42.1% pathologic complete responses have been seen at esophagectomy. Therefore, preoperative chemoradiation therapy can be anticipated for better prognosis of the patients with locally advanced esophageal cancer.

[Sexual dysfunction following pelvic surgery]

In male, sexual dysfunction was a common complication that occurred after radical pelvic surgery: radical protectomy, radical cysto-, prostatectomy. Upon the recent pelvic neuroanatomical findings and preservation of these nerves, it is now possible to perform successful cancer operation on the rectum, prostate or bladder with preservation of sexual function in the group of early cancer patients. Depending on the location and severity of these nerve injury, this could result in temporary or permanent erectile and ejaculation dysfunction. In female, the total hysterectomy for cervical cancer sacrifices or injuries the faculty of pregnancy or sexual intercourse. The oophorectomies causes a deficiency of female hormones. But recently the numbers of patients with a small or early stages cancer of uterine or ovary are increasing and we have become to be able to save the functions of these organs in many patients well with minimum local excision or partial resection of them.

[Prospective controlled study on the usefulness of Carmofur as a postoperative adjuvant chemotherapy for colorectal cancer]

A prospective controlled study, the 7th cooperative study of the Japanese Foundation for Multidisciplinary Treatment, was conducted to evaluate the usefulness of concomitant therapy with MMC + HCFU as a postoperative adjuvant therapy in patients with colorectal cancer who had undergone curative resection for a period of 2 years and 11 months from February, 1986. The Dukes B and C patients with colorectal cancer classified by macroscopic examination who had an intravenous MMC 6 mg/m2 on the day of operation and followed by oral HCFU for 12 months from 2 weeks after operation (Group X) were compared with patients who had operation only (Group Y). Some 978 patients with colon cancer and 713 patients with rectal cancer were enrolled in the study, 85 (5.0%) of whom were not eligible. The 5-year survival rate of Group X in colon cancer was 79.3% and that of Group Y was 76.4%: thus the survival rate of Group X was slightly better than that of Group Y, but no significant difference was found between the two groups. Subset analysis revealed that the survival rate of Group X in advanced cancer of stage III b + IV, according to the General Rules for Clinical and Pathological Studies on Cancer of the Colon, Rectum and Anus in Japan, was 62.4% and that of Group Y was 46.2%. Thus, the survival rate of Group X was significantly better than that of Group Y (logrank test: p = 0.035, generalized Wilcoxon test: p = 0.025). The disease-free survival rate was not significantly different between the groups with colon cancer and rectal cancer. The above results suggest that HCFU is useful for patients with a high risk of recurrence who had advanced colon cancer (stage III b + IV). However, additional prospective studies are required to verify them.

Oxysterols found in opacified cornea of fish

We describe a new concept implicating oxidized cholesterol derivatives and very long-chain fatty acids as possible factors in the development of corneal opacification after death. Corneal tissues, removed from both fresh and stale fish eyes, were examined for cholesterol derivatives and fatty acids after methanolysis of lipids. Cholesta-3,5-dien-7-one, cholest-4-en-3-one, hexacosenoic acid, and hexacosenoic acid were identified via gas chromatography/mass spectrometry in opacified corneas, but not in significant amounts in fresh ones. The present study confirmed the presence of lipid hydrolysis and a peroxidation process in the opacified cornea.

Thymic nurse cells as the site of thymocyte apoptosis and apoptotic cell clearance in the thymus of cyclophosphamide-treated mice

Structural changes in the thymus of BALB/c mice after the intraperitoneal injection with a single high dose (200 mg/kg) of cyclophosphamide (CY) were examined. A large number of thymic nurse cell (TNC)-like structures that contained apoptotic thymocytes were observed in the thymus between 8 and 20 hours after CY treatment, just before a marked reduction in the number and proportion of PNAhi, CD3-, CD4+ CD8+ thymocytes. The majority of apoptotic thymocyte-containing TNC-like structures had an epithelial nature and were mainly located in the subcapsular and outer cortex, perivascular area of the cortex, corticomedullary junction and, in part, in the medulla. Most thymocytes seemed to undergo apoptosis synchronously in every TNC-like structure, but one or two fully intact mature thymocytes were found in every one. By 24 hours after CY treatment, many vacuoles that contained apoptotic cells in various stages of degeneration were observed within the epithelium, and most of the apoptotic cells disappeared at 24 hours. We herein demonstrated that the epithelium of TNC-like structures had a phagocytic activity in the digestion of apoptotic thymocytes by the presence of phagolysosomes with acid phosphatase activity. The epithelium left very small vacuoles with a small amount of nondigestible dense granules. The minority of apoptotic thymocyte-containing TNC-like structures scattered in the entire cortex between 8 and 20 hours after CY treatment was macrophage (M phi)-derived. Many apoptotic cell-containing M phi were observed as early as 4 hours after the CY injection. Apoptotic thymocytes of CY-treated mice showed the internucleosomal DNA fragmentation. In conclusion, CY accelerates physiologic thymocyte apoptosis, and epithelial TNC are one of the principal sites of thymocyte apoptosis as well as an environment for the nursing of immature thymocytes. Both the epithelium of TNC and M phi participate in digestion of apoptotic cells and have the efficient capacity of clearance of apoptotic thymocytes in the normal thymus at a presumed high rate.

Identification of cholesta-3,5-dien-7-one by gas chromatography-mass spectrometry in the erythrocyte membrane of alcoholic patients

Lipids and oxidized lipids were analyzed by gas chromatography-mass spectrometry in the erythrocyte membranes of alcoholic and control subjects. Cholesta-3,5-dien-7-one and cholesta-trienes were detected in alcoholic samples examined, but not in significant amounts in controls. Levels of polyunsaturated fatty acids (arachidonic acid, 20:4; docosahexaenoic acid, 22:6; and docosatetraenoic acid, 22:4) in alcoholic samples declined significantly, whereas cholesta-3,5-dien-7-one levels increased. A high level of total bilirubin was observed in most patients. A possible mechanism of the accumulation of cholesta-3,5-dien-7-one in the erythrocyte membrane of alcoholics is discussed.

Reaction of 20S proteasome: shift of SDS-dependent activation profile by divalent cations

The multicatalytic endopeptidase complex (20S proteasome) is a latent high-molecular-mass multisubunit proteinase. In many investigations, SDS has been used as a proteasome activator at some fixed concentration that was apparently optimal. This study examined the effects of various divalent cations on the SDS-dependent peptidase and casein degradation activities of 20S proteasome purified from Xenopus laevis oocytes at a series of SDS concentrations and the correlation between these effects and the critical micelle concentration (CMC) of SDS. Surprisingly, it was found that divalent cations such as Mg2+ markedly shifted the SDS-dependent activation profiles to a lower concentration range. Ca2+, Mn2+, Co2+, and Zn2+ also markedly reduced the optimum SDS concentration in the Suc-Leu-Leu-Val-Tyr-MCA hydrolysis reaction: for example, 5 mM Co2+ reduced the optimum SDS concentration from 0.065 to 0.005%. However, in all cases examined the optimum concentrations were below the CMC. Cu2+, Hg2+, and Cd2+ strongly inhibited the SDS-dependent maximum activity without remarkably shifting the optimum SDS concentration. No correlation between the shift and the inhibition was recognized. Most interestingly, remarkable activation of casein degradation by SDS was observed only by addition of the divalent cations Mg2+, Ca2+, and Mn2+. These cations might be essential for casein degradation. The activation and inactivation ranges of SDS concentration varied with the species of substrate.(ABSTRACT TRUNCATED AT 250 WORDS)

Congenital myotonic dystrophy: molecular diagnosis and clinical study

Recently, an unstable DNA fragment specific to myotonic dystrophy (MyD) was discovered. In affected individuals, a DNA fragment is found that is larger than in normal siblings. Our objectives were to show whether the results of DNA analysis agree with the disease severity and prognosis in congenital myotonic dystrophy (CMyD) by DNA analysis. We investigated three pregnancies (two studied retrospectively) in three families. We genotyped the family members with the Southern blots and the polymerase chain reaction (PCR) analysis. In one case a prenatal diagnosis was carried out using chorionic villus sampling. This report also presents the three cases of affected mothers and CMyD babies with their growth courses. We clarify four main problems in CMyD, namely, respiratory distress, delayed motor development, feeding difficulty, and delayed mental development. The allele size in the range of 10 to 13 kb tended to be present as the adult form of MyD, and 14 to 15 kb as the CMyD. The three CMyD cases whose alleles size in the range of 14 to 15 kb showed various forms of disease and prognosis. We reached the following conclusions: the disease severity and prognosis in babies with CMyD did not correlate with the result of DNA analysis. The DNA analysis is a useful test for prenatal diagnosis. However, it is impossible to predict the disease severity and prognosis in babies with CMyD.

Murine nursing thymic epithelial cell lines capable of inducing thymocyte apoptosis express the self-superantigen Mls-1a

Two cloned thymic epithelial cell (TEC) lines, D2.TEC-A3 and AKR TEC-K1, were established from minor lymphocyte-stimulating (Mls)-1a-positive normal, 4-week-old DBA/2 (H-2d, Mls-1a2a) mice and AKR (H-2k, Mls-1a2b) mice, respectively. Both cell lines were MHC class I and class II (both I-A and I-E) positive without stimulation by interferon-gamma. They were capable of infolding immature thymocytes to form thymic nurse cells (TNC; we call this type of TEC "nursing TEC") and induced apoptosis with DNA fragmentation in immature thymocytes. Using a primary Mls mixed lymphocyte reaction (MLR) we demonstrated that self-superantigen Mls-1a was expressed on these cloned nursing TEC lines. D2.TEC-A3 cells stimulated nylon-wool-purified splenic T cells obtained from H-2d-compatible BALB/c (Mls-1b2a) and B10.D2 (Mls-1b2b) mice with a maximal response at a stimulator:responder ratio of 1:40 after 4 days of the coculture. AKR TEC-K1 cells also stimulated purified T cells from H-2k-compatible C3H/He mice (Mls-1b2a) in a similar manner. The Mls MLR induced by the nursing TEC lines was completely inhibited in the presence of anti-mouse I-A and anti-mouse I-E monoclonal antibodies. These results suggest that nursing TEC/TNC could be involved in negative selection due to apoptosis.

[Chronological changes in autoantigenicity of autologous testicular germ cells in C3H/He mice during the postnatal period]

Our recent studies demonstrated that experimental autoimmune orchitis (EAO) model was produced in C3H/He mice with high incidence by two subcutaneous injections of viable syngeneic testicular germ cells (TC) without the use of any adjuvants or immunopotentiators. In this study the developmental patterns of autoantigenicity of TC during postnatal period were investigated by examining the orchitogenic activity of TC, the lymphostimulatory activities of TC (including the TC-induced in vitro lymphocyte proliferative response and the cytokine release from sensitized spleen cells (SPC) in response to TC) and the immunohistochemical localization of target autoantigens in the testes of mice at various weeks of age. Delayed-type hypersensitivity-inducing capacity and anti-TC antibody-eliciting capacity were initially observed in mice that were immunized with TC of 4-week old (w.o.) mice. The TC from 6-w.o. mice had the capability of inducing EAO (orchitogenicity) for the first time. A significant stimulation of in vitro lymphocyte proliferative response, as well as of interleukin (IL) 5 and IL-6 production by sensitized SPC were detectable when TC of mice 3-w.o. or more than were employed as stimulant. IL-2 and interferon gamma production were detected with TC of 4-w.o. mice. Immunohistochemical staining reaction with anti-TC antisera was primarily localized at the acrosomal portion of spermatids and spermatozoa in the seminiferous tubules, being already detected in spermatids of as early as 3-w.o. mice. Thus, from these data it is suggested that the appearance of the lymphostimulatory activities of TC consistently precedes that of the orchitogenic activity and that relatively mature germ cells such as spermatids and spermatozoa developing in the testes during the postnatal weeks may be responsible for the induction of disease and relevant immune responses in our EAO system.

An analysis on the effect of blood transfusion on recurrence and survival in patients undergoing extended lymphadenectomy for colorectal cancer

In a retrospective study data were collected from 644 patients with cancer of the colon or rectum undergoing curative surgery with extended lymphadenectomy to evaluate a possible effect of blood transfusion, given perioperatively, on tumor recurrence and patient survival. Univariate analysis showed depth of bowel wall invasion, number and level of lymph node metastases to be of highly significant prognostic factors. After 5 years the overall recurrence rate was 16.6% for the non-transfused (n = 223) and 26.1% for the transfused (n = 421; p < .01) patients, and survival rates showed borderline significance favoring the non-transfused patients (90.5% vs. 80.0% after 5 years; p < 0.05). However, after stratification for the prognostically important factors, in a multivariate analysis a possible detrimental effect of perioperative blood transfusions could not be demonstrated.

Generation and characterization of a continuous line of CD8+ suppressively regulatory T lymphocytes which down-regulates experimental autoimmune orchitis (EAO) in mice

We have previously shown that two injections with viable syngeneic testicular germ cells (TC) alone developed experimental autoimmune orchitis (EAO) in C3H/He mice, and that the induction of antigen-specific tolerance in this EAO model is associated with the generation of antigen-specific suppressively regulatory T (Ts) cells. For the elucidation of the nature of these Ts cells, a murine Ts cell line (designated Ts-A) was established. This line was generated from the spleen cells of C3H/He mice which had received three i.v. injections of a soluble (deaggregated) form of murine testicular antigen (mTA), followed by the repeated selection of these spleen lymphocytes in vitro by stimulation with mTA. Adoptive transfer of Ts-A cells into naive syngeneic mice immediately before the first TC injection was found to downgrade EAO in actively immunized recipients. The transferred Ts-A cells significantly inhibited the cellular immune response to TC in the recipients in an antigen-specific manner, but these cells had no inhibitory effect on the humoral immune response to TC. This line could also inhibit in vitro syngeneic TC-driven proliferation of orchitogenic lymphocytes. Surface phenotype of this line was CD8+, CD4-, Thy-1.2+, CD3+, and TCR alpha beta+. These findings may suggest an in vivo role for suppressively regulatory lymphocytes, capable of inhibiting helper T cells, in the regulation of EAO.

Murine experimental autoimmune orchitis (EAO) induced by syngeneic testicular germ cells (TC) alone: orchitogenic and lymphostimulatory activities of TC from mice at various ages

As part of our continuous investigations on the immune pathogenesis of a new experimental autoimmune orchitis (EAO) model without the use of adjuvant in C3H/He mice, the developmental patterns of autoantigenicity of viable syngeneic testicular germ cells (TC) during the postnatal period were investigated by examining the orchitogenic and immunogenic activities of TC, the lymphostimulatory activities of TC (the cytokine release from sensitized spleen cells (SPC) in response to TC), and the immunohistochemical localization of autoantigens in the testes of normal mice at various weeks of age. TC from 6-week-old mice had the capability of inducing EAO (orchitogenicity) for the first time. Delayed-type hypersensitivity-inducing capacity and anti-TC antibody-eliciting capacity were initially observed in mice immunized with TC from 4-week-old mice. A significant stimulation of interleukin 5 (IL-5) and interleukin 6 (IL-6) production by sensitized SPC was detectable when the TC from 3-week or older mice were employed as a stimulant. Interleukin 2 (IL-2) and interferon-gamma (IFN-gamma) production was detected with TC from 4-week or older mice. Immunohistochemical staining reaction with anti-TC antisera was primarily localized at the acrosomal portion of spermatids and spermatozoa in the seminiferous tubules and was detected in early and late spermatids of mice as early as 3 weeks. Thus, from these chronological data it is suggested that the appearance of the lymphostimulatory activities of TC consistently precedes that of the orchitogenic activity and that the production of IL-5 and IL-6 (Th 2 cytokine) by sensitized SPC upon in vitro TC stimulation is detectable earlier than the production of IL-2 and IFN-gamma (Th 1 cytokine) in the postnatal period.

Pattern of recurrence after hepatic resection for colorectal metastases

Between 1978 and 1989, 159 patients with liver metastases from colorectal cancer underwent hepatic resection. Of 134 patients in whom metastases were confined to the liver, 109 had tumours removed completely with histologically negative resection margins. Two patients died in hospital. Ultrasonographically guided partial resection was performed in 80 patients, lateral segmentectomy in seven and lobectomy in 22. The 5-year survival rate of patients undergoing potentially curative resection was 47.9 per cent. Patients with metachronous tumours showed a significantly better prognosis than those with synchronous lesions in both univariate (P < 0.01) and multivariate (P = 0.01) analysis. During a median follow-up of 35.4 months, 64 patients developed recurrence, including 34 in the liver, 20 in the lung and 12 in the abdominal cavity. Of those with hepatic recurrence, ten patients developed tumours at the initial resection bed, seven in the same lobe, five in the contralateral lobe and 12 in both lobes. Ultrasonographically guided partial liver resection did not increase the risk of hepatic recurrence.