Factors associated with regional nodal failure in patients with early stage breast cancer with 0-3 positive axillary nodes following tangential irradiation alone

PURPOSE

Recent randomized trials have suggested that improved local-regional control after radiation therapy significantly increases survival for breast cancer patients with positive axillary nodes treated with adjuvant systemic therapy (1, 2). It has been our policy to use a third radiation field only in patients with 4 or more positive nodes. The purpose of this study was to assess whether there are any clinical or pathologic factors associated with an increased risk of regional nodal failure (RNF) in patients with 0-3 positive nodes treated with tangential radiotherapy (RT) alone with or without systemic therapy.

METHODS AND MATERIALS

We retrospectively analyzed the incidence of RNF for 691 patients with clinical Stage I or II invasive breast cancer treated with complete gross excision of the primary tumor and tangential RT alone between 1978-87; 12% also received systemic therapy. All had 0-3 positive nodes on axillary dissection that had histologic examination of > or =6 nodes, and all had potential 8-year follow-up. The median number of axillary nodes removed was 11 (range 6-36). RNF was defined as any recurrence in ipsilateral axillary, internal mammary, supraclavicular, or infraclavicular nodes in the absence of recurrence in the breast, with or without simultaneous distant metastasis. Crude rates for first sites of failure within the first 8 years after treatment were calculated. A polychotomous logistic regression was used to identify factors prognostic for RNF and other sites of first failure.

RESULTS

Within 8 years, RNF was the first site of failure for 27 patients for a crude 8-year rate of 3.9%. Isolated axillary failure occurred in 8 patients (1.2%). Isolated supraclavicular and/or infraclavicular failure occurred in 5 (1.3%) and 3 (0.4%) patients, respectively. Isolated internal mammary node failure occurred in 2 patients (0.3%). A polychotomous logistic regression model of first site of failure (local failure, regional nodal, distant/ opposite breast, dead without recurrence, no evidence of disease) within 8 years found age <50 years, moderate or marked necrosis, size greater than 1 cm, and presence of an extensive intraductal component (EIC) to be significantly correlated with site of first failure, but only the last two were associated with a significantly larger relative risk of RNF versus being no evidence of disease at 8 years. The incidence of RNF was 0.7% for patients with tumors < or =1 cm compared to 5.7% among patients with larger tumors. Among patients with EIC-positive tumors the incidence of RNF was 7.6% compared to 3.1% among those whose tumors were EIC-negative.

CONCLUSIONS

Although the incidence of RNF has been shown to be somewhat higher in patients with tumors measuring greater than 1 cm and those with an EIC, RNF is uncommon among all subsets of patients with negative or 1-3 positive lymph nodes treated with conservative surgery, axillary dissection, and only tangential RT fields. Therefore, giving only tangential RT (without a separate nodal field) appears generally acceptable for patients with 0-3 positive nodes.

Association of age and reproductive factors with benign breast tissue composition

Reproductive breast cancer risk factors are hypothesized to act by increasing exposure of the breast to endogenous estrogens, but few studies have quantitatively examined the association of these risk factors with breast tissue composition. This study is part of a case-control study of breast histological characteristics and breast cancer risk, nested within the Nurses' Health Study, a prospective study of 121,700 registered nurses. We studied 300 women who had not been diagnosed with breast cancer, but for whom we obtained slides from a prior benign breast biopsy. We used a computer-assisted image analysis technique to assess the proportion of epithelial and fibrous stromal tissue on benign breast biopsy slides, excluding obvious mass lesions. Mean epithelial proportion was 5.3% (0.1-23%), and mean stromal proportion was 58.7% (3-93%). Women with proliferative breast disease without atypia had higher epithelial and stromal proportions than women with nonproliferative breast disease (P < 0.001). Postmenopausal women had a lower epithelial proportion (P = 0.01), and increasing age at biopsy was associated with decreasing stromal proportion among postmenopausal parous women (P = 0.004). Among premenopausal women, increasing years since last birth was associated with lower epithelial proportion (P < 0.001). Other reproductive risk factors were not independently associated with epithelial or stromal proportion. Epithelial and stromal breast tissue were associated with different factors with the exception of proliferative breast disease, which was associated with an increase in both epithelial and stromal proportion. The quantitative measurement of epithelial and stromal proportion may be useful for measuring changes in breast composition.

Developmental delay in P300 production in children at high risk for developing alcohol-related disorders

BACKGROUND

Reduction of P300 amplitude in children and adolescents at high risk for developing alcoholism has frequently been reported. It has been hypothesized that this reduction represents a developmental delay in reaching age-appropriate levels in P300 amplitude. Using latent growth analysis of longitudinal data obtained at yearly intervals, this study seeks to define normal growth, and determine if the pattern seen in high-risk children differs from that obtained in normal low-risk controls.

METHODS

A total of 156 children from either high or low-risk families have been assessed multiple times (two-thirds more than 4 times) using both a clinical assessment (K-SADS) and ERP evaluation performed on the same day. A total of 635 separate assessments were available for modeling.

RESULTS

Quadratic growth curves revealed a slower rate of change in P300 amplitude in high-risk than low-risk males. High-risk girls showed reduced visual P300 amplitude only when the presence of a K-SADS diagnosis was considered. No differences were seen for P300 latency.

CONCLUSIONS

This study confirms the hypothesis that when reduction of P300 amplitude is seen in males at high risk for developing alcoholism, it is due to a developmental delay.

Psychopathology and achievement in children at high risk for developing alcoholism

OBJECTIVE

To compare rates of psychopathology and academic achievement in children who were either at high or low risk for developing alcoholism and to determine whether academic deficits would predict prospectively the presence of psychopathology occurring within the next year.

METHOD

Children and adolescents, aged 8 to 18 years, were evaluated as part of a longitudinal follow-up. Diagnoses obtained by using the Schedule for Affective Disorders and Schizophrenia for School-Age Children and grade-equivalent scores from the reading, spelling, and arithmetic sections of the Wide Range Achievement Test were determined at yearly intervals.

RESULTS

High-risk offspring were more likely to have a diagnosable disorder. In addition, analyses using the mother's and father's diagnosis of alcoholism as a covariate showed higher hazard ratios for selected disorders (depression, affective disorder, attention-deficit/hyperactivity disorder, and conduct disorder), some of which were gender-dependent. Logistic regression analysis of achievement test scores demonstrated that reading and math scores predicted the presence of childhood psychopathology at the following annual evaluation.

CONCLUSIONS

Children from pedigrees with a high density of alcoholism are at greater risk for developing psychopathology. Furthermore, observed deficits in academic performance may be considered an indicator of a developing diagnosable illness.

Structural basis of activation and GTP hydrolysis in Rab proteins

BACKGROUND

Rab proteins comprise a large family of GTPases that regulate vesicle trafficking. Despite conservation of critical residues involved in nucleotide binding and hydrolysis, Rab proteins exhibit low sequence identity with other GTPases, and the structural basis for Rab function remains poorly characterized.

RESULTS

The 2. 0 A crystal structure of GppNHp-bound Rab3A reveals the structural determinants that stabilize the active conformation and regulate GTPase activity. The active conformation is stabilized by extensive hydrophobic contacts between the switch I and switch II regions. Serine residues in the phosphate-binding loop (P loop) and switch I region mediate unexpected interactions with the gamma phosphate of GTP that have not been observed in previous GTPase structures. Residues implicated in the interaction with effectors and regulatory factors map to a common face of the protein. The electrostatic potential at the surface of Rab3A indicates a non-uniform distribution of charged and nonpolar residues.

CONCLUSIONS

The major structural determinants of the active conformation involve residues that are conserved throughout the Rab family, indicating a common mode of activation. Novel interactions with the gamma phosphate impose stereochemical constraints on the mechanism of GTP hydrolysis and provide a structural explanation for the large variation of GTPase activity within the Rab family. An asymmetric distribution of charged and nonpolar residues suggests a plausible orientation with respect to vesicle membranes, positioning predominantly hydrophobic surfaces for interaction with membrane-associated effectors and regulatory factors. Thus, the structure of Rab3A establishes a framework for understanding the molecular mechanisms underlying the function of Rab GTPases.

Demonstration of phase correlation in multiwavelength mode-locked semiconductor diode lasers

Wideband spectral phase correlation is demonstrated from a multiwavelength mode-locked semiconductor laser. By use of frequency-resolved optical gating techniques, significant phase correlation was observed between multiple intracavity oscillating wavelengths, with wavelength separations of ~1 nm . The resultant temporal characteristics show a substantial modulation owing to the spectral coupling induced by intracavity-generated four-wave mixing. This result may lead to novel methods for directly generating ultrafast subpicosecond optical pulse sequences with spectrally tailored amplitude and phase characteristics from actively mode-locked semiconductor lasers.

Radial scars in benign breast-biopsy specimens and the risk of breast cancer

BACKGROUND

Radial scars are benign breast lesions of uncertain clinical significance. In particular, it is not known whether these lesions alter the risk of breast cancer in women with benign breast disease. We conducted a case-control study of women who had benign breast lesions with or without radial scars.

METHODS

We reviewed benign breast-biopsy specimens from 1396 women enrolled in the Nurses' Health Study, including 255 women in whom breast cancer subsequently developed and 1141 women without subsequent breast cancer (controls). The controls were matched to the women with subsequent breast cancer according to age and the year when the benign lesion was identified. The median follow-up after biopsy of the benign lesions was 12 years.

RESULTS

Radial scars were identified in biopsy specimens from 99 women (7.1 percent). Most biopsy specimens with radial scars had only one radial scar (60.6 percent), and they tended to be incidental microscopical findings (median size, 4.0 mm). The women with radial scars had a risk of breast cancer that was almost twice the risk of the women without scars, regardless of the histologic type of benign breast disease (relative risk, 1.8; 95 percent confidence interval, 1.1 to 2.9). Among women who had proliferative disease without atypia as compared with women who had nonproliferative disease, the relative risk of breast cancer was 3.0 (95 percent confidence interval, 1.7 to 5.5) for those with radial scars and 1.5 (95 percent confidence interval, 1.1 to 2.1) for those without radial scars. Among women with atypical hyperplasia as compared with women with nonproliferative disease, the relative risk of breast cancer was 5.8 (95 percent confidence interval, 2.7 to 12.7) for those with radial scars and 3.8 (95 percent confidence interval, 2.4 to 5.9) for those without radial scars.

CONCLUSIONS

Radial scars are an independent histologic risk factor for breast cancer.

Correlation of tumor size and axillary lymph node involvement with prognosis in patients with T1 breast carcinoma

BACKGROUND

The prognosis of patients with T1 breast carcinoma remains controversial. Some studies have shown a low risk of lymph node metastasis and distant failure whereas others have not, possibly due to differences in the definition of tumor size. In this study, the authors assessed the relation between macroscopic tumor size, microscopic invasive tumor size, axillary lymph node involvement, and prognosis in a group of patients with clinically lymph node negative disease.

METHODS

Between 1968 and 1986, 1865 women with American Joint Committee on Cancer clinical Stage I or II infiltrating carcinoma of the breast were treated at the Joint Center for Radiation Therapy with conservative surgery and radiation therapy. The study population was limited to 118 patients with clinically negative axillary lymph nodes for whom the macroscopic pathologic tumor size was identified unambiguously as being < or = 2.0 cm, who underwent an axillary lymph node dissection with at least 6 lymph nodes sampled, and for whom the microscopic size of the invasive component could be determined. The median follow-up time for surviving patients was 134 months (range, 90-208 months). No patients with pathologically negative axillary lymph nodes received systemic therapy.

RESULTS

Macroscopic and microscopic tumor sizes differed by > 5 mm in 17 patients (14%), by 3-5 mm in 24 patients (20%), and by < or = 2 mm in 77 patients (65%). The macroscopic tumor size was smaller than the microscopic size in 37 patients (31%), larger in 55 patients (47%), and equal in 26 patients (22%). Pathologic axillary lymph node involvement was present in 21% of all patients. The risk of lymph node involvement was not significantly different for those patients with tumors < or = 1 cm compared with patients with tumors > or = 1.1 cm, regardless of whether tumor size was measured by macroscopic or microscopic examination. The 10-year actuarial rate of freedom from distant recurrence (FFDR) was 91% for lymph node negative patients with macroscopic tumors measuring < or = 1.0 cm compared with 77% for patients with macroscopic tumors measuring > or = 1.1 cm (P = 0.07). When measured microscopically, the rates were 96% and 72%, respectively (P = 0.001).

CONCLUSIONS

There often is a discrepancy between microscopic tumor size and macroscopic tumor size. T1 tumors have a substantial risk of axillary lymph node metastasis whether measured macroscopically or microscopically. Among those patients with pathologic lymph node negative tumors who are not treated with systemic adjuvant therapy, microscopic invasive tumor size is a better predictor of 10-year FFDR than macroscopic tumor size. There is a substantial risk of distant failure for patients with tumors whose invasive component microscopically measure > or = 1.1 cm, whereas the prognosis for patients with tumors that microscopically measured < or = 1 cm is excellent. These results suggest that the microscopic size of the invasive component of breast carcinomas < or = 2.0 cm routinely should be reported.

Columnar alteration with prominent apical snouts and secretions: a spectrum of changes frequently present in breast biopsies performed for microcalcifications

We have noted in breast biopsies performed for microcalcifications a spectrum of lesions in the terminal duct lobular unit (TDLU) characterized by columnar epithelial cells with prominent apical cytoplasmic snouts, intraluminal secretions, and varying degrees of nuclear atypia and architectural complexity. The appearance of some of these lesions is worrisome, but diagnostic difficulties arise because the histologic features do not fulfill established criteria for the diagnosis of atypical ductal hyperplasia or ductal carcinoma in situ (DCIS). We have termed such lesions columnar alteration with prominent apical snouts and secretions (CAPSS). The purpose of this study was to define the pathologic spectrum and mammographic features of these lesions. We reviewed histologic sections and mammograms from 100 consecutive breast biopsies performed for microcalcifications. The prevalence and histologic features of CAPSS and the association with other histologic findings were recorded. CAPSS was identified in 42% of cases. At the lower end of the spectrum were lesions similar to columnar alteration of lobules but in which apical cytoplasmic secretion and nuclear stratification were more pronounced and cells with a hobnail configuration were common. More advanced lesions showed columnar epithelial cell tufts, bridges, and micropapillations with prominent apical cytoplasmic snouts and with greater degrees of nuclear stratification and atypia. At the upper end of the spectrum were lesions that could arguably be considered DCIS. Calcifications were present within CAPSS in 74% of cases, were frequently psammomatous, and were typically nonbranching and often round on mammography. Columnar alteration of lobules was more common in biopsies with than without CAPSS (74 versus 36%, p < 0.001). Ductal carcinoma in situ was seen with similar frequency in biopsies with and without CAPSS (38 versus 41%). However, DCIS in cases with CAPSS was more often of the low-grade micropapillary-cribriform type than in cases without CAPSS (56 versus 17%, p < 0.01), and CAPSS and DCIS commonly coexisted in the same or adjacent TDLUs. In conclusion, 1) CAPSS encompasses a spectrum of lesions bounded at the lower end by columnar alteration of lobules and at the upper end by low-grade DCIS. Lesions recently described by Page as "hypersecretory hyperplasia with atypia" fall within this spectrum. 2) Some CAPSS lesions present architectural or cytologic features that create diagnostic difficulties and raise the possibility of atypical ductal hyperplasia or DCIS; however, the level of cancer risk associated with CAPSS lesions that do not fulfill established criteria for atypical ductal hyperplasia or DCIS is unknown and requires evaluation in follow-up studies.

Maternal-fetal tolerance is maintained despite transgene-driven trophoblast expression of MHC class I, and defects in Fas and its ligand

During mammalian pregnancy, one or more semiallogeneic fetuses gestate in direct contact with the maternal circulation and uterine tissue. However, a damaging maternal immune response is not normally provoked. We studied two possible mechanisms for this maternal-fetal tolerance, alone and in combination. First, we directly tested the hypothesis that the striking absence of MHC class I molecules on most placenta trophoblasts protects the fetus from maternal immune attack, by creating transgenic mice which express Ld in giant cell trophoblasts. Second, because Fas ligand (FasL) may contribute to immune privilege, we tested whether functional FasL expression by the fetus, or Fas expression by the mother, contributes to successful reproduction in a fully allogeneic breeding. Our data indicate that neither abnormal expression of MHC class I in giant cells, nor disruption of the Fas-FasL system, nor a combination of these two defects, has an adverse effect on pregnancy outcome. These results suggest that during healthy allogeneic pregnancy, down-regulation of MHC class I and expression of FasL on placenta are not critical events, and other factors must prevent a harmful maternal immune response.

Reovirus growth in cell culture does not require the full complement of viral proteins: identification of a sigma1s-null mutant

The reovirus sigma1s protein is a 14-kDa nonstructural protein encoded by the S1 gene segment. The S1 gene has been linked to many properties of reovirus, including virulence and induction of apoptosis. Although the function of sigma1s is not known, the sigma1s open reading frame is conserved in all S1 gene sequences determined to date. In this study, we identified and characterized a variant of type 3 reovirus, T3C84-MA, which does not express sigma1s. To facilitate these experiments, we generated two monoclonal antibodies (MAbs) that bind different epitopes of the sigma1s protein. Using these MAbs in immunoblot and immunofluorescence assays, we found that L929 (L) cells infected with T3C84-MA do not contain sigma1s. To determine whether sigma1s is required for reovirus infection of cultured cells, we compared the growth of T3C84-MA and its parental strain, T3C84, in L cells and Madin-Darby canine kidney (MDCK) cells. After 48 h of growth, yields of T3C84-MA were equivalent to yields of T3C84 in L cells and were fivefold lower than yields of T3C84 in MDCK cells. After 7 days of growth following adsorption at a low multiplicity of infection, yields of T3C84-MA and T3C84 did not differ significantly in either L cells or MDCK cells. To determine whether sigma1s is required for apoptosis induced by reovirus infection, T3C84-MA and T3C84 were tested for their capacity to induce apoptosis, using an acridine orange staining assay. In these experiments, the percentages of apoptotic cells following infection with T3C84-MA and T3C84 were equivalent. These findings indicate that nonstructural protein sigma1s is not required for reovirus growth in cell culture and does not influence the capacity of reovirus to induce apoptosis. Therefore, reovirus replication does not require the full complement of virally encoded proteins.

Quantitation of progesterone receptor mRNA in breast carcinoma by branched DNA assay

Expression of progesterone receptor (PR) mRNA is indicative of a normal gene regulation mechanism mediated by functional estrogen receptor (ER). A simple assay which can reliably detect and quantitate PR mRNA levels in a small amount of tissue will be of value for studying functional status of ER. We have developed a quantitative nucleic acid hybridization assay for PR mRNA in breast carcinoma. The assay, which is based on the branched DNA (bDNA) technology, is simple, highly specific, and reproducible, requires 20 mg of tissue, and correlates reasonably well (r = 0.86) with an established methodology. The assay has a dynamic range of 3 x 10(3)-6 x 10(7) copies of PR mRNA per well. PR message as high as 3.9 x 10(5) copies per well could be detected in normal breast tissues. Thus a sensitivity of 3 x 10(3) PR copies per well was sufficient for testing clinical samples. In the present studies, accurate measurement of tissue weight enabled direct reporting of the PR mRNA values as the end point results. The bDNA assay provides a useful tool for the detection and quantitation of PR mRNA in research and routine clinical laboratories.

Home-based versus hospital-based care for serious mental illness. Controlled cost-effectiveness study over four years

BACKGROUND

The Daily Living Programme (DLP) offered intensive home-based care with problem-centred case management for seriously mentally ill people facing crisis admission to the Maudsley Hospital, London. The cost-effectiveness of the DLP was examined over four years.

METHOD

A randomised controlled study examined cost-effectiveness of DLP versus standard in/out-patient hospital care over 20 months, followed by a randomised controlled withdrawal of half the DLP patients into standard care. Three patient groups were compared over 45 months: DLP throughout the period, DLP for 20 months followed by standard care, and standard care throughout. Bivariate and multivariate analyses were conducted (the latter to standardise for possible inter-sample differences stemming from sample attrition and to explore sources of within-sample variation).

RESULTS

The DLP was more cost-effective than control care over months 1-20, and also over the full 45-month period, but the difference between groups may have disappeared by the end of month 45.

CONCLUSIONS

The reduction of the cost-effectiveness advantage for home-based care was perhaps partly due to the attenuation of DLP care, although sample attrition left some comparisons under-powered.

Family history and treatment outcome in young women after breast-conserving surgery and radiation therapy for early-stage breast cancer

PURPOSE

To evaluate the safety and efficacy of breast-conserving therapy for young women with a family history (FH) suggestive of inherited breast cancer susceptibility.

MATERIALS AND METHODS

A total of 201 patients aged 36 or younger at diagnosis treated with breast-conserving surgery and radiation therapy (> or = 60 Gy) for early-stage breast cancer were categorized by FH. FH was considered positive in 29 patients who, at the time of diagnosis, had a mother or sister previously diagnosed with breast cancer before age 50 or ovarian cancer at any age. Clinical, pathologic, and demographic variables; sites of first failure; disease-free survival; and overall survival (OS) were compared between FH-positive and -negative groups. Median follow-up time was 11 years.

RESULTS

Patient and tumor features were similar between those with and without an FH. Regression analysis of sites of first failure at 5 years demonstrated a risk ratio (RR) of 5.7 for opposite breast cancer for FH-positive patients. Rates of local, regional, and distant failure and disease-free survival or OS did not differ between FH-positive and -negative patients. Age at diagnosis and Ashkenazi heritage were not significantly predictors of patterns of failure.

CONCLUSION

Breast-conserving surgery combined with radiation therapy is not associated with a higher rate of local recurrence, distant failure, or second (non-breast) cancers in young women with an FH suggestive of inherited breast cancer susceptibility compared with young women without an FH. However, their increased risk of opposite breast cancer should be taken into account when considering breast conservation as a treatment option.

Predictors of breast recurrence after conservative surgery and radiation therapy for invasive breast cancer

The majority of women with breast cancer are adequately treated with breast-conserving surgery and radiation therapy. Although most women need very limited surgery, some require a larger volume of resection to attain a high level of local control, and some might even require a mastectomy. This article summarizes the current state of knowledge concerning the assessment of the adequacy of excision.

Skin recurrences after breast-conserving therapy for early-stage breast cancer

PURPOSE

To assess the frequency and prognosis of skin recurrences after breast-conserving therapy (BCT) compared with other breast recurrences.

MATERIALS AND METHODS

From 1968 to 1986, 1,624 patients with unilateral stage I or II breast cancer treated with BCT at the Joint Center for Radiation Therapy (Boston, MA) underwent gross tumor excision and received a dose of > or = 60 Gy to the tumor bed. Skin recurrences (SR) were defined as breast recurrences without associated parenchymal disease. An invasive breast recurrence with any parenchymal disease noted clinically or radiographically was scored as an other breast recurrence (OBR). Median follow-up for survivors was 137 months.

RESULTS

SR represented 8% (18 of 229) of all breast recurrences and occurred in 1.1% of all patients. The outcome after local recurrence was different for patients with SR and invasive OBR. Patients with SR more frequently had uncontrolled local failure (50%; 9 of 18) than did patients with OBR (14%; 26 of 188) (P = .0007). Forty-four percent (8 of 18) of patients with SR had distant metastasis simultaneously or within 2 months of the recurrence compared with 5% (9 of 188) of invasive OBR patients (P < .0001). For patients without distant metastasis at the time of recurrence, the 5-year actuarial rate of development of distant metastasis was 60% for SR patients compared with 39% for invasive OBR patients (P = .07), and the corresponding 5-year actuarial survival rates beyond the time of local failure were 51% and 79%, respectively (P = .06).

CONCLUSION

In contrast to other types of invasive breast recurrence after breast-conserving therapy, skin recurrences are rare and are associated with a significantly higher rate of distant metastasis and uncontrolled local disease as well as a lower rate of survival.

The familial aggregation of adolescent suicide attempts

The objective of this study was to determine whether the familial aggregation of suicidal behaviour is explained by the familial aggregation of personality disorder and aggression. The relatives of 62 clinically referred adolescent suicide attempters were compared with 70 never-suicidal psychiatric controls. The first-degree relatives of the suicide attempters had a higher rate of suicide attempts/completion than those of the psychiatric controls. This rate remained significantly higher after controlling for Axis I and II differences in the probands and the relatives, but familial personality disorder was significantly associated with suicidal risk in probands. Among the adolescent attempters, high scores on a measure of assaultiveness were associated with significantly higher familial rates of suicide attempts/completion. Our results support the hypothesis that suicidal behaviour may be transmitted as a trait independent of Axis I and II psychopathology but that, in addition, personality disorder has a role in the transmission of suicidal behaviour. An interrelationship between proband assaultiveness and the familial aggregation of suicidality was noted.

Paracetamol poisoning in the north east of England: presentation, early management and outcome

1. Paracetamol is increasingly involved in self-poisoning in the United Kingdom and remains a common cause of fatal poisoning. 2. To document the epidemiology and early management of paracetamol poisoning data were collected on consecutive patients with suspected paracetamol poisoning presenting to 6 hospitals in the North East of England over 12 weeks in 1994. 3. There were 400 presentations (attendance rate 1.14/10(3) population/yr) involving 343 persons (45% male). Paracetamol concentrations at 4 h correlated weakly with reported paracetamol dose (R = 0.49, P < 0.0001) and were similar comparing those treated and not treated by gastric decontamination. 4. In 38 (9%) cases paracetamol concentrations were above the appropriate nomogram treatment line, including 3% and 20% of patients who reported ingesting less than and more than 12 g respectively. In 21 patients acetylcysteine treatment was deferred until admission to the ward, the mean delay involved was 2.8 h. 5. One patient died, from arrhythmias caused by co-ingested dothiepin. 6. Paracetamol poisoning is common. Most cases do not have potentially toxic plasma paracetamol concentrations, but those who do often present late and antidotal treatment may be delayed inappropriately.