Showing papers by "Leicester Royal Infirmary published in 1990"
TL;DR: The technique has proved to be an effective method of treating occlusions of the femoral and popliteal arteries with an acceptable complication rate and may allow successful angioplasty where the standard intraluminal method fails, particularly when reconstructive surgery is the only option.
Abstract: A technique for recanalization of femoral and popliteal arterial occlusions by intentional subintimal dissection is described. Recanalization with this technique was attempted in 71 occlusions of the femoro-popliteal segment with a mean length of 11.4 cm. Primary technical success was achieved in 54 (76%) cases, with complications occurring in 4 (5.6%). Of 44 successful cases reviewed at a mean follow up of 6 months, 37 (84%) were either asymptomatic or improved. The technique has proved to be an effective method of treating occlusions of the femoral and popliteal arteries with an acceptable complication rate. It may allow successful angioplasty where the standard intraluminal method fails, particularly when reconstructive surgery is the only option.
315 citations
TL;DR: The Townes-Brocks syndrome derives its eponymous title from the names of the two authors who, in 1972, described variable anal, hand, foot, and ear anomalies in a father and five of his seven children.
Abstract: The Townes-Brocks syndrome derives its eponymous title from the names of the two authors who, in 1972, described variable anal, hand, foot, and ear anomalies in a father and five of his seven children.' Shortly afterwards, similar abnormalities were documented in 19 subjects from four generations of a large Australian family.2 Subsequent reports of both familial3-6 and isolated6-9 cases have established the Townes-Brocks syndrome as a discrete entity and enabled fuller delineation of the phenotype of what appears to be a relatively rare disorder. Individual patients or families or both have been reported from North America, 3 6 8 Australia,2 4 Belgium,5 Brazil,7 and Portugal.9
116 citations
TL;DR: An in situ hybridization technique has been developed for the detection of immunoglobulin light chain mRNA in routine pathology specimens using a cocktail of synthetic oligonucleotide probes labelled with biotin or fluorescein 5‐isothiocyanate (FITC) reporter molecules.
Abstract: An in situ hybridization technique has been developed for the detection of immunoglobulin light chain mRNA in routine pathology specimens. The method detects kappa or lambda constant region sequences using a cocktail of synthetic oligonucleotide probes labelled with biotin or fluorescein 5-isothiocyanate (FITC) reporter molecules. The probes were labelled at flanking sites chemically by primary amine directed acylation and by 'homopolymer tailing' with terminal deoxynucleotidyl transferase using non-radioactive nucleotide analogues. The mRNA was unmasked in the formalin-fixed tissue sections by digestion with varying concentrations of proteinase K, and the hybrids were demonstrated using alkaline phosphatase with either a streptavidin/biotin based four-stage system or an anti-FITC antibody based detection system. Alkaline phosphatase was visualized using a Fast Red naphthol-capture method and the sections were counterstained with haematoxylin. The results confirm that the method is specific for kappa or lambda mRNA and show that specific mRNAs can be detected in routine formalin-fixed sections using non-radioactive techniques with retention of good morphology. The method reliably detects light chain mRNA in cells expressing secretory immunoglobulin. The protocol can also be applied to tissue rich in endogenous biotin by using hapten-labelled probes.
85 citations
TL;DR: It was found that, for more than 98% of the 1280 frames of Doppler signals analyzed, the order selected by the various criteria was ten or less, and overestimating the model order is better than underestimating it.
Abstract: Autoregressive modelling includes a model identification procedure, that is, it is necessary to choose the order of the autoregressive (AR) process that best describes the given finite record (frame) of the signal. Four previously suggested procedures to choose the "best order" of AR processes have been tested: The "first zero crossing" of the autocorrelation function (FZC), the "final prediction error" (FPE), "Akaike's information criterion" (AIC), and the "criterion autoregressive transfer-function" (CAT). It was found that: (i) For more than 98% of the 1280 frames of Doppler signals analyzed the order selected by the various criteria was ten or less. (ii) For the same records of Doppler signals, FPE, AIC and CAT behave in a very similar manner, but the FZC criterion underestimates the order in relation to the others. (iii) For true AR processes, the order selected is frequently different from the true AR order when frames of 64 samples are used. When more samples are used FPE, AIC and CAT tend to select the correct order. (iv) The effect on the spectral estimate of using too high a model order is usually insignificant, while using too low an order can change the estimate more dramatically, that is, overestimating the model order is better than underestimating it.
65 citations
TL;DR: It is concluded that, while GOR and obstructive episodes may co-exist in the patient groups studied, decreases in pH in the lower oesophagus do not usually induce either central or obstructive apnoea, and vice versa.
Abstract: We studied the relation of gastro-oesophageal reflux with apnoea during sleep in 24 infants with antecedent respiratory abnormalities and/or proven gastro-oesophageal reflux (GOR), by combined lower oesophageal pH and polygraphic monitoring. GOR, indicated by pH 20s) central apnoea (CA). Fifty-six mixed or obstructive breathing episodes were identified in 12 infants (14 studies), of which 28 lasted between 3 and 6s. Bradycardia (heart rate less than 5 mmHg) but only 6 exceeded 10 mmHg and one 20 mmHg. There was no relationship between GOR and obstructive episodes in terms of frequency, duration or temporal occurrence, except in one infant. There were 1276 gross body movements, mainly during active or indeterminate sleep and, of these, 7% were associated with decreases in pH to 1 pH unit compared to only 30% in the 60s succeeding a pH drop. We conclude that, while GOR and obstructive episodes may co-exist in the patient groups studied, decreases in pH in the lower oesophagus do not usually induce either central or obstructive apnoea, and vice versa. Of the variables monitored, only gross body movements were temporally associated with pH drops, and usually preceded them.
62 citations
TL;DR: Place of delivery of premature babies (less than or equal to 27 weeks' gestation) may influence classification and hence figures for perinatal mortality, and the fact that the onus of judgment regarding viability and classification is often placed on relatively junior staff might also affect the figures.
Abstract: OBJECTIVE--To examine how local attitudes to management of extreme preterm labour can influence data on perinatal mortality. DESIGN--One year prospective study in a geographically defined population. SETTING--The 17 perinatal units of Trent region. PATIENTS--All preterm infants of less than or equal to 32 weeks' gestation in the Trent region. INTERVENTIONS--Infants who had been considered viable at birth were referred for intensive care; those who had been considered non-viable received terminal care. MAIN OUTCOME MEASURES--Whether each infant was born alive, dead, or alive but considered non-viable. RESULTS--Large differences were observed among units in the rates of delivery of infants of less than or equal to 27 weeks' gestation (rates varied from 7.2 to 0 per 1000 births). These differences were not present in the data relating to infants of between 28 and 32 weeks' gestation. The variation seemed to result from different approaches to the management of extreme preterm labour--that is, whether management took place in a labour ward or a gynaecology ward. CONCLUSIONS--Place of delivery of premature babies (less than or equal to 27 weeks' gestation) may influence classification and hence figures for perinatal mortality. In addition, the fact that the onus of judgment regarding viability and classification is often placed on relatively junior staff might also affect the figures for perinatal mortality. The introduction of a standard recording system for all infants greater than 500 g would be advantageous.
61 citations
TL;DR: During the late stages of both pregnancies maternal oestriol levels were unrecordable and there was evidence of suppression of maternal adrenal function, speculation on the existence of a primary defect in the fetal adrenals is speculated.
Abstract: Two cases of Smith-Lemli-Opitz syndrome type II are presented. During the late stages of both pregnancies maternal oestriol levels were unrecordable and there was evidence of suppression of maternal adrenal function. We speculate on the existence of a primary defect in the fetal adrenals.
60 citations
TL;DR: There was a large rise in the number of new melanomas presenting in Leicestershire: from 1.02 per week before the campaign to 1.88 per week in the immediate postpublicity period, which was statistically significant (P<0.001).
Abstract: We report our experience of the initial effects of a publicity campaign directed at early presentation of malignant melanoma in Leicestershire. The campaign resulted in a dramatic increase in workload and, at the pigmented lesion clinic, the numbers of new patients rose from 12.3 to 54.5 per clinic. There was a large rise in the number of new melanomas presenting in Leicestershire: from 1.02 per week before the campaign to 1.88 per week in the immediate post-publicity period. This was statistically significant (P less than 0.001). Although there was also an apparently encouraging rise in the percentage of thinner 'good prognosis' tumours, it was not possible to isolate this statistically from a pre-existing trend.
54 citations
TL;DR: Proximal fibular osteotomy appears to be a causative factor in the development of common peroneal nerve palsy; more work is needed on the blood supply of the nerve.
Abstract: We assessed 16 patients before and after high tibial osteotomy by electrophysiological recordings, creatine phosphokinase levels, radiographs and intracompartmental pressure monitoring. We found mild electrophysiological abnormalities pre-operatively in 12 of the 16 patients, but postoperatively these had deteriorated in 11 of the 14 patients studied. Creatine phosphokinase levels, compartment pressure and radiological deformity were not predictive of the development of postoperative common peroneal nerve palsy. Patients who also had a proximal fibular osteotomy had greater electrical abnormalities postoperatively and two of them developed common peroneal palsies. Proximal fibular osteotomy appears to be a causative factor in the development of common peroneal nerve palsy; more work is needed on the blood supply of the nerve.
53 citations
TL;DR: All but one of the children had unusual forms of the disease and there was a family history of lichen planus in three children seen in the outpatients clinic.
Abstract: Summary
We present the features of six children who have been seen amongst 154 consecutive new patients with lichen planus in our outpatients clinic. All but one of the children had unusual forms of the disease and there was a family history of lichen planus in three. Lichen planus is rare in childhood and often assumes atypical clinical patterns.
51 citations
TL;DR: There is a definite association between EBV and HD, although the exact nature of this association remains to be established and it has been shown that DNA of sufficient quality for the detection of EBV DNA can be extracted from formalin-fixed, paraffin-embedded material, and that comparable results can be obtained using DNA extracted from fresh and fixed tissue.
Abstract: The presence of Epstein-Barr virus (EBV) DNA in formalin-fixed, paraffin-embedded samples of Hodgkin's disease (HD) was investigated by Southern blot hybridization using a specific EBV Bam H1W fragment probe. DNA from 16 samples of HD in children and young adults was compared with that from ten samples in adults older than 45 years. A further eight cases of DNA extracted from fresh samples of HD were also studied, in order to compare the results obtained with fresh and fixed tissue samples.
Hybridization was demonstrated in 15 of the 34 cases of HD studied in contrast to 3 or the 34 control specimens of non-Hodgkin's lymphoma, non-neoplastic lymph nodes, and carcinomas. No differences between the two age groups compared were found.
The results of this study suggest that there is a definite association between EBV and HD, although the exact nature of this association remains to be established. It has also been shown that DNA of sufficient quality for the detection of EBV DNA can be extracted from formalin-fixed, paraffin-embedded material, and that comparable results can be obtained using DNA extracted from fresh and fixed tissue.
TL;DR: Caudal bupivacaine provided more pain‐free patients at first but later the incidence of pain was similar in the two treatment groups and rectal diclofenac is a useful alternative to caudal blockade in this group of patients.
Abstract: Summary
Forty-three children for day case inguinal herniotomy under general anaesthesia were assigned randomly to receive either 1 ml/kg caudal bupivacaine 0.25% or rectal diclofenac 0.25 mg/kg intra-operatively to provide postoperative analgesia. Pain and demeanour were assessed by an observer in the early postoperative period after operation and by questionnaire for the parents over the first 24 hours. Caudal bupivacaine provided more pain-free patients at first but later the incidence of pain was similar in the two treatment groups. Rectal diclofenac is a useful alternative to caudal blockade in this group of patients.
TL;DR: Although HLA‐DR staining is associated with tumors of better prognosis, it cannot be used as an independent prognostic factor, and the authors conclude that the difference on multivariate analysis was not statistically significant.
Abstract: The prognostic value of histochemical staining for HLA-DR was assessed retrospectively in 52 "curative" gastrectomy specimens from patients with gastric carcinoma. In addition other tumor variables, including histologic type, degree of differentiation, extent of local spread, prominence of mononuclear infiltrate, tumor edge, and lymph-node metastases, were examined. Sixty-five percent of the tumors showed positive staining for HLA-DR, and these tumors had a higher mean and median survival at 5 years compared with negative tumors. However, on multivariate analysis the difference was not statistically significant. The authors conclude that, although HLA-DR staining is associated with tumors of better prognosis, it cannot be used as an independent prognostic factor. Of the other tumor variables, only lymph-node status was of prognostic significance.
Journal Article•
TL;DR: A controlled clinical study comparing skin incision by conventional scalpel with electrosurgical needle incision has shown the latter technique to be highly effective, consistently quicker, and to give better cosmetic results with minimal complications.
Abstract: A controlled clinical study comparing skin incision by conventional scalpel with electrosurgical needle incision has shown the latter technique to be highly effective, consistently quicker, and to give better cosmetic results with minimal complications. It is a convenient technique and well tolerated by the patients with no added discomfort. Skin diathermy burns and wound haematomas were only seen after conventional scalpel incision. Fears of delayed wound healing, keloid formation and high infection rates are unfounded.
TL;DR: It is demonstrated that the accumulation of 1,2-diacylglycerol generated from inositol lipid breakdown is only observed with activation by angiotensin II, and phosphatidic acid may play a more prominent role during the sustained phase of contraction than previously anticipated.
TL;DR: A 19 year old male veterinary nurse accidentally injected himself with 200 mg of xylazine, and became comatose, hypotensive, bradycardic and acidotic, and made a full recovery over the next few hours.
Abstract: A 19 year old male veterinary nurse accidentally injected himself with 200 mg of xylazine (a muscle relaxant and sedative used in veterinary practice). He subsequently became comatose, hypotensive, bradycardic and acidotic. He required intensive supportive therapy, and made a full recovery over the next few hours. Xylazine toxicity in humans is very rare, and the effects are discussed.
TL;DR: The main finding in the study was an increase in the plucked telogen count, maximal at 12 weeks, and the predominant cause of this increase was a decrease in the duration of anagen.
Abstract: Twenty-two patients receiving etretinate were studied in an attempt to clarify the changes in hair cycle dynamics responsible for etretinate alopecia. Shed hair counts and telogen counts on samples of plucked hair were performed prior to therapy and after 6 and 12 weeks' treatment with etretinate. No evidence of anagen effluvium was found. In two individuals there were findings compatible with a classical telogen effluvium, but these had atypical features. The main finding in the study was an increase in the plucked telogen count, maximal at 12 weeks. As an arrest in the onset of anagen could produce only a comparatively small telogen increase, the predominant cause of this increase was a decrease in the duration of anagen. In two subjects there was also evidence of a telogen anchorage defect.
TL;DR: Mitoxantrone is an active agent in the treatment of acute leukemia and demonstrates incomplete cross resistance with duanorubicin and should be considered for first‐line therapy in ANLL.
Abstract: Seventy-seven patients with relapsed or refractory acute leukemia and three with acute blastic chronic myeloid leukemia (CML) were treated in an open Phase II study using mitoxantrone 12 mg/m2 intravenously daily X 5 days. Complete remission (CR) was achieved in 32 of 80 (40%), including 23/45 (52%) with relapsed acute nonlymmphocytic leukemia (ANLL), four of 12 (33%) with relapsed acute lymphocytic leukemia ALL, four of 17 (24%) with ANLL refractory to daunorubicin + cytosine arabinoside, and one of three (33%) with refractory ALL. None of the patients with acute blastic CML achieved CR. Median survival time for all patients was 121 days. Median duration of complete response was 303 days with ten of 32 patients in continuing CR for periods varying from 44+ to 1210+ days. Apart from moderately prolonged hematologic suppression toxicity was mild and subjective side effects were tolerable. Mitoxantrone is an active agent in the treatment of acute leukemia and demonstrates incomplete cross resistance with duanorubicin. Mitoxantrone should be considered for first-line therapy in ANLL.
TL;DR: Findings have a considerable impact on the diagnosis of abnormal gastro-oesophageal reflux and its response to treatment whether using 24 hour pH monitoring or any other method of measurement.
Abstract: Thirteen infants who had undergone 24 hour oesophageal pH monitoring to diagnose gastro-oesophageal reflux had a second study carried out to see if the results were reproducible. The studies were done without restricting the babies' activities. Appreciable differences were found, the percentage of the total time during which the pH was less than 4 varying by up to 3.7-fold between the two tests. The differences were largely the result of biological rather than technical variability. From these results estimates were made of the reliability of a single diagnostic study and the size of changes that would be necessary to show the effect of treatment. These findings have a considerable impact on the diagnosis of abnormal gastro-oesophageal reflux and its response to treatment whether using 24 hour pH monitoring or any other method of measurement.
TL;DR: Observations suggest that IGF-bp1 is primarily related to luteinization of the granulosa and the resultant luteal cells, and if produced by the lutea cells, additional exogenous factors are required to induce production by granul Rosa cells in vitro.
Abstract: The occurrence of pregnancy-associated endometrial alpha 1-globulin (alpha 1-PEG), a 29-32 kd insulin-like growth factor binding protein, now termed type 1 or IGF-bp1, has been examined in the human ovary by monoclonal and polyclonal antibody based radioimmunoassay and immunohistological techniques. Follicular fluids aspirated from 51 follicles of 32 women undergoing hyperstimulation involving buserelin or clomiphene-based protocols contained 35.5-276.0 ng/ml (mean 101.0 mg/ml) of immunoreactive IGF-bp1. Mean fluid concentrations were three times the level of IGF-bp1 detected in paired serum samples, available for 21 women. Immunoreactive IGF-bp1 in follicular fluid exhibited similar dose-response curves to purified protein and amniotic fluid and immunoreactive IGF-bp1 coeluted in gel filtration with a peak of [125I]-IGF-1 binding corresponding to the elution profile of purified IGF-bp1. Gel filtration also revealed the presence in follicular fluid of a greater than 100 kd binding protein with a binding capacity equal to IGF-bp1 under the conditions employed. A highly significant correlation (P less than 0.001) was found between follicular fluid progesterone and IGF-bp1 and a correlation of lower significance was found between oestradiol and IGF-bp1 (P less than 0.05). However, only low levels of immunoreactive IGF-bp1 were detected in supernatant media of granulosa cells in culture (range undetectable to 2.3 ng/ml). Employing monoclonal antibody-based immunohistology, immunoreactive IGF-bp1 was consistently associated with luteinized granulosa cells of corpora lutea rather than paraluteal cells and its intensity of reactivity appeared to reflect luteal phase steroid hormone profiles. No consistent reactivity was detected in preovulatory follicles and granulosa cells in culture, although reactivity was associated with primordial oocytes. Immunoreactive IGF-bp1 was detected in six of nine supernatant media of explants of luteal tissue obtained from five corpora lutea, with levels ranging from undetectable to greater than 200 ng/ml. These observations suggest that IGF-bp1 is primarily related to luteinization of the granulosa and the resultant luteal cells, and if produced by the luteal cells, additional exogenous factors are required to induce production by granulosa cells in vitro.
TL;DR: A simple radiographic technique for the diagnosis of non-union of Colles' fractures is described, using flexion and extension views of the wrist, and a method of treatment is outlined.
Abstract: There are few reports in the literature concerning non-union of Colles' fractures or its treatment. We describe two cases in which the fractures had been treated in the standard manner by reduction and plaster immobilisation for six weeks. The wrists of both patients were mobilised free of external support for several months before the complication of non-union was diagnosed. A simple radiographic technique for the diagnosis of non-union is described, using flexion and extension views of the wrist, and a method of treatment is outlined.
TL;DR: The distance from skin to the epidural space was measured in 163 patients receiving epidural analgesia and the mean distance was found to be 4.78 cm, which correlated with other anatomic measurements.
Abstract: The distance from skin to the epidural space was measured in 163 patients receiving epidural analgesia. The mean distance was found to be 4.78 cm, which correlated with other anatomic measurements. The presence of edema and the ethnic origin of the patients had significant effects on this distance.
TL;DR: The clinical behaviour and surgical findings suggest the lesion to be an invasive malignancy, but the histological appearance of an admixture of chronic inflammatory cells and fibrosis is consistent with a benign condition.
Abstract: The term 'tumefactive fibroinflammatory lesion' has been used to describe a fibrosclerosing disorder which has a locally destructive nature but is characterized by a benign histological appearance. We report five patients, over a five year period, with such a lesion. The clinical behaviour and surgical findings suggest the lesion to be an invasive malignancy. However, the histological appearance of an admixture of chronic inflammatory cells and fibrosis is consistent with a benign condition. We recommend surgical excision of the lesion as the mainstay of treatment; other studies report the use of steroids and radiotherapy.
TL;DR: It is concluded that to delay pushing beyond 60 min confers no benefit regarding mode of delivery and women who waited more than 60 min were less likely to experience a normal spontaneous delivery.
Abstract: We studied primigravid women in spontaneous labor at term and given epidural analgesia Two hundred such women giving birth in 1983 were compared with similar groups who gave birth in 1985 and 1987 after the introduction of 'delayed pushing' into our labor ward protocol Four hundred controls were obtained in 1983 and 1985 by selecting from the labor ward register the next normal primigravid woman in spontaneous labor without epidural analgesia the assisted delivery rate was significantly higher in all three epidural groups than in the controls (p < 0001) Among epidural labors, there was no significant difference between 1983 and 1987 in the incidence of rotational or non-rotational forceps, or of cesarean section In each epidural group, women who waited more than 60 min were less likely to experience a normal spontaneous delivery than were those who did not (p < 0001 in 1983; p = 0006 in 1985 p = 0035 in 1987) We conclude that to delay pushing beyond 60 min confers no benefit regarding mode of de
TL;DR: Haemodynamic changes and plasma catecholamine concentrations were measured in 12 patients aged 24 to 87 years after performance of a field block for elective repair of inguinal or femoral hernia, thought to be related to the peak plasma concentrations of adrenaline produced.
Abstract: Summary
Haemodynamic changes and plasma catecholamine concentrations were measured in 12 patients aged 24 to 87 years after performance of a field block for elective repair of inguinal or femoral hernia. The local anaesthetic used comprised a mixture of lignocaine 0.5% with adrenaline 1:200000; the dose of lignocaine administered varied from 3.8 mg/kg to 4.9 mg/kg. Plasma adrenaline increased by 326% and plasma noradrenaline by 75% at 10 minutes after completion of the block. Mean heart rate increased from 75 to 94 beats/minute after 20 minutes, whilst there were no obvious changes in systolic and diastolic arterial pressures. Potentially serious arrhythmias developed in two patients, thought to be related to the peak plasma concentrations of adrenaline produced. It is recommended that the dose of adrenaline used as described for this block should be reduced.
TL;DR: The first case of inflammation of the retinal pigment epithelium (RPE) caused by Schistosoma mansoni is reported and its possible pathogenesis is discussed.
Abstract: We report the first case of inflammation of the retinal pigment epithelium (RPE) caused by Schistosoma mansoni and discuss its possible pathogenesis. This is of particular interest because the lesions resembled those found in acute multifocal placoid pigment epitheliopathy (AMPPE).
TL;DR: A patient is described in whom erythema induratum and papulonecrotic tuberculide occurred simultaneously and clinical and histological appearances were characteristic as was the response to antituberculous chemotherapy.
Abstract: Summary
A patient is described in whom erythema induratum and papulonecrotic tuberculide occurred simultaneously. Clinical and histological appearances were characteristic as was the response to antituberculous chemotherapy.
TL;DR: It was concluded that over short periods of time, measures based on the LEDS and IMSR are independent, but that major social disruptions may have life long effects on social support networks.
Abstract: Life events and supportive social networks are often treated as separate independent variables in their relations with supposed dependent variables such as depressive disorder. It is important therefore to establish that they are independent of one another. One hundred and twenty one men and women attending psychiatric hospitals with depressive disorders were interviewed at the time of their initial contact by a research psychiatrist and a week later by a non-clinical research worker who enquired about life events (LEDS) and about social networks (IMSR). One hundred and eleven patients were successfully followed up in the same manner, typically 4 months later. Social networks were very stable over time. Where they did change, this could not be explained in terms of losses of social contact due to events such as death of a primary group member. The rating of threatening events and difficulties was also unrelated to the quality of social support networks. Institutional rearing in childhood was associated with substantially smaller adult primary networks. It was concluded that over short periods of time, measures based on the LEDS and IMSR are independent, but that major social disruptions may have life long effects on social support networks.
01 Dec 1990
TL;DR: This is the first in vivo study to show reduced colorectal carcinogenesis by N-6 polyunsaturated fatty acids in rats fed the saturated fat diets.
Abstract: The influence of dietary fats on azoxymethane-induced colorectal carcinogenesis and erythrocyte, adipose, colon mucosa and tumour tissue fatty acids was investigated in 228 Wistar rats. The two main diets compared were beef suet rich in saturated fatty acids and corn oil rich in a linoleic acid, an N-6 polyunsaturated fatty acid. The animals were placed in one of four dietary groups: A = 5% saturated fat, B = 20% saturated fat, C = 5% N-6 fat and D = 20% N-6 fat. There was no difference in the number of adenomas between any of the dietary groups. The mean (+/- SEM) carcinoma yield per rat was A = 0.93 +/- 0.28, B = 1.93 +/- 0.50, C = 0.70 +/- 0.07, D = 0.13 +/- 0.04; the tumour yields in rats fed the saturated fat diets were significantly different from each other and from those fed the N-6 fat diets. The fatty acid profiles in all tissues were dependent upon the type and level of dietary fat and the tissue type. Arachidonate was higher in tumours compared to normal mucosa. Significant correlations were found between adipose linoleate (reflecting dietary intake) and tumour oleate and tumour arachidonate but not with the colorectal mucosa of control animals. This is the first in vivo study to show reduced colorectal carcinogenesis by N-6 polyunsaturated fatty acids.