Passive or active drainage system for chronic subdural haematoma-a single-center retrospective follow-up study.

BACKGROUND: Postoperative drainage systems have become a standard treatment for chronic subdural hematoma (CSDH). We previously compared treatment results from three Scandinavian centers using three different postoperative drainage systems and concluded that the active subgaleal drainage was associated with lower recurrence and complication rates than the passive subdural drainage. We consequently changed clinical practice from using the passive subdural drainage to the active subgaleal drainage. OBJECTIVE: The aim of the present study was to assess a potential change in reoperation rates for CSDH after conversion to the active subgaleal drainage. METHODS: This single-center cohort study compared the reoperation rates for recurrent same-sided CSDH and postoperative complication rates between patients treated during two study periods (passive subdural drainage cohort versus active subgaleal drainage cohort). RESULTS: In total, 594 patients were included in the study. We found no significant difference in reoperation rates between the passive subdural drain group and the active subgaleal drain group (21.6%, 95% CI 17.5-26.4% vs. 18.0%, 95% CI 13.8-23.2%; p = 0.275). There was no statistical difference in the rate of serious complications between the groups. The operating time was significantly shorter for patients operated with the active subgaleal drain than patients with the passive subdural drain (32.8 min, 95% CI 31.2-34.5 min vs. 47.6 min, 95% CI 44.7-50.4 min; p < 0.001). CONCLUSIONS: Conversion from the passive subdural to the active subgaleal drainage did not result in a clear reduction of reoperation rates for CSDH in our center.

Surgery for herniated lumbar disc in private vs public hospitals: A pragmatic comparative effectiveness study.

BACKGROUND: There is limited evidence on the comparative performance of private and public healthcare. Our aim was to compare outcomes following surgery for lumbar disc herniation (LDH) in private versus public hospitals. METHODS: Data were obtained from the Norwegian registry for spine surgery. Primary outcome was change in Oswestry disability index (ODI) 1 year after surgery. Secondary endpoints were quality of life (EuroQol EQ-5D), back and leg pain, complications, and duration of surgery and hospital stays. RESULTS: Among 5221 patients, 1728 in the private group and 3493 in the public group, 3624 (69.4%) completed 1-year follow-up. In the private group, mean improvement in ODI was 28.8 points vs 32.3 points in the public group (mean difference - 3.5, 95% CI - 5.0 to - 1.9; P for equivalence < 0.001). Equivalence was confirmed in a propensity-matched cohort and following mixed linear model analyses. There were differences in mean change between the groups for EQ-5D (mean difference - 0.05, 95% CI - 0.08 to - 0.02; P = 0.002) and back pain (mean difference - 0.2, 95% CI - 0.2, - 0.4 to - 0.004; P = 0.046), but after propensity matching, the groups did not differ. No difference was found between the two groups for leg pain. Complication rates was lower in the private group (4.5% vs 7.2%; P < 0.001), but after propensity matching, there was no difference. Patients operated in private clinics had shorter duration of surgery (48.4 vs 61.8 min) and hospital stay (0.7 vs 2.2 days). CONCLUSION: At 1 year, the effectiveness of surgery for LDH was equivalent in private and public hospitals.

Accuracy and complication rates of external ventricular drain placement with twist drill and bolt system versus standard trephine and tunnelation: a retrospective population-based study.

BACKGROUND: An external ventricular drain (EVD) is typically indicated in the presence of hydrocephalus and increased intracranial pressure (ICP). Procedural challenges have prompted the development of different methods to improve accuracy, safety, and logistics. OBJECTIVES: EVD placement and complications rates were compared using two surgical techniques; the standard method (using a 14-mm trephine burrhole with the EVD tunnelated through the skin) was compared to a less invasive method (EVD placed through a 2.7-3.3-mm twist drill burrhole and fixed to the bone with a bolt system). METHODS: Retrospective observational study in a single-centre setting between 2008 and 2018. EVD placement was assessed using the Kakarla scoring system. We registered postoperative complications, surgery duration and number of attempts to place the EVD. RESULTS: Two hundred seventy-two patients received an EVD (61 bolt EVDs, 211 standard EVDs) in the study period. Significant differences between the bolt system and the standard method were observed in terms of revision surgeries (8.2% vs. 21.5%, p = 0.020), surgery duration (mean 16.5 vs. 28.8 min, 95% CI 7.64, 16.8, p < 0.001) and number of attempts to successfully place the first EVD (mean 1.72 ± 1.2 vs. 1.32 ± 0.8, p = 0.017). There were no differences in accuracy of placement or complication rates. CONCLUSIONS: The two methods show similar accuracy and postoperative complication rates. Observed differences in both need for revisions and surgery duration favoured the bolt group. Slightly, more attempts were needed to place the initial EVD in the bolt group, perhaps reflecting lower flexibility for angle correction with a twist drill approach.

Surgery for extraforaminal lumbar disc herniation: a single center comparative observational study.

BACKGROUND: Surgery on extraforaminal lumbar disc herniation (ELDH) is a commonly performed procedure. Operating on this type of herniation is known to come with more difficulties than on the frequently seen paramedian lumbar disc herniation (PLDH). However, no comparative data are available on the effectiveness and safety of this operation. We sought out to compare clinical outcomes at 1 year following surgery for ELDH and PLDH. METHODS: Data were collected through the Norwegian Registry for Spine Surgery (NORspine). The primary outcome measure was change at 1 year in the Oswestry Disability Index (ODI). Secondary outcome measures were quality of life measured with EuroQol 5 dimensions (EQ-5D); and numeric rating scales (NRSs). RESULTS: Data of a total of 1750 patients were evaluated in this study, including 72 ELDH patients (4.1%). One year after surgery, there were no differences in any of the patient reported outcome measurements (PROMs) between the two groups. PLDH and ELDH patients experienced similar changes in ODI (- 30.92 vs. - 34.00, P = 0.325); EQ-5D (0.50 vs. 0.51, P = 0.859); NRS back (- 3.69 vs. - 3.83, P = 0.745); and NRS leg (- 4.69 vs. - 4.46, P = 0.607) after 1 year. The proportion of patients achieving a clinical success (defined as an ODI score of less than 20 points) at 1 year was similar in both groups (61.5% vs. 52.7%, P = 0.204). CONCLUSIONS: Patients operated for ELDH reported similar improvement after 1 year compared with patients operated for PLDH.

Lumbar microdiscectomy for sciatica in adolescents: a multicentre observational registry-based study.

BACKGROUND: Lumbar disc herniation (LDH) is rare in the adolescent population. Factors predisposing to LDH in adolescents differ from adults with more cases being related to trauma or structural malformations. Further, there are limited data on patient-reported outcomes after lumbar microdiscectomy in adolescents. Our aim was to compare clinical outcomes at 1 year following single-level lumbar microdiscectomy in adolescents (13-19 years old) compared to younger adults (20-50 years old) with LDH. METHODS: Data were collected through the Norwegian Registry for Spine Surgery. Patients were eligible if they had radiculopathy due to LDH, underwent single-level lumbar microdiscectomy between January 2007 and May 2014, and were between 13 and 50 years old at time of surgery. The primary endpoint was change in Oswestry Disability Index (ODI) 1 year after surgery. Secondary endpoints were generic quality of life (EuroQol five dimensions [EQ-5D]), back pain numerical rating scale (NRS), leg pain NRS and complications. RESULTS: A total of 3,245 patients were included (97 patients 13-19 years old and 3,148 patients 20-50 years old). A significant improvement in ODI was observed for the whole population, but there was no difference between groups (0.6; 95% CI, -4.5 to 5.8; p = 0.811). There were no differences between groups concerning EQ-5D (-0.04; 95% CI, -0.15 to 0.07; p = 0.442), back pain NRS (-0.4; 95% CI, -1.2 to 0.4; p = 0.279), leg pain NRS (-0.4; 95% CI, -1.2 to 0.5; p = 0.374) or perioperative complications (1.0% for adolescents, 5.1% for adults, p = 0.072). CONCLUSIONS: The effectiveness and safety of single-level microdiscectomy are similar in adolescents and the adult population at 1-year follow-up.

Is surgery for recurrent lumbar disc herniation worthwhile or futile? A single center observational study with patient reported outcomes.

Objective: To examine outcomes and complications following microdiscectomy for recurrent lumbar disc herniation. Methods: Prospectively collected data for patients operated at the Department of Neurosurgery, St. Olavs University Hospital, Norway, were obtained from the Norwegian Registry for Spine Surgery from May 2007 through July 2016. All patients underwent lumbar microdiscectomy. The primary outcome was change in the Oswestry Disability Index (ODI) at one year. Secondary endpoints were change in quality of life measured with EuroQol 5 Dimensions (EQ-5D), back and leg pain measured with numerical rating scales (NRS), complications, and duration of surgery and hospital stays. Results: 276 patients were enrolled in the study. A total of 161 patients (58.3%) completed one-year follow-up. The mean improvement in ODI at one year was 27.1 points (95% CI 23.1 to 31.0, P <0.001). The mean improvement in EQ-5D at one year of 0.47 points (95% CI 0.40-0.54, P <0.001), representing a large effect size (Cohens D â€‹= â€‹1.3). The mean improvement in back pain and leg pain NRS were 4.3 points (95% CI 2.2-3.2, P <0.001) and 3.8 points (95% CI 2.8-3.9, P <0.001), respectively. Nine patients (3.3%) experienced intraoperative complications, and 15 (5.5%) out of 160 patients reported complications within three months following hospital discharge. Conclusions: This study shows that patients operated for recurrent lumbar disc herniation in general report significant clinical improvement.

Can a Successful Outcome After Surgery for Lumbar Disc Herniation Be Defined by the Oswestry Disability Index Raw Score?

STUDY DESIGN: Prospective multicenter cohort study. OBJECTIVE: To investigate (1) the discriminative ability and cutoff estimates for success 12 months after surgery for lumbar disc herniation on the Oswestry Disability Index (ODI) raw score compared with a change and a percentage change score and (2) to what extent these clinical outcomes depend on the baseline disability. METHODS: A total of 6840 patients operated for lumbar disc herniation from the Norwegian Registry for Spine Surgery (NORspine) were included. In receiver operating characteristic (ROC) curve analyses, a global perceived effect (GPE) scale (1-7) was used an external anchor. Success was defined as categories 1-2, "completely recovered" and "much better." Cutoffs for success for subgroups with different preoperative disability were also estimated. RESULTS: When defining success after surgery for lumbar disc herniation, the accuracy (sensitivity, specificity, area under the curve, 95% CI) for the ODI raw score (0.83, 0.87, 0.930, 0.924-0.937) was comparable to the ODI percentage change score (0.85, 0.85, 0.925, 0.918-0.931), and higher than the ODI change score (0.79, 0.73, 0.838, 0.830-0.852). The cutoff for success was highly dependent on the amount of baseline disability (low-high), with cutoffs ranging from 13 to 28 for the ODI raw score and 39% to 66% for ODI percentage change. The ODI change score (points) was not as accurate. CONCLUSION: The 12-month ODI raw score, like the ODI percentage change score, can define a successful outcome with excellent accuracy. Adjustment for the baseline ODI score should be performed when comparing outcomes across groups, and one should consider using cutoffs according to preoperative disability (low, medium, high ODI scores).

Microdiscectomy for Lumbar Disc Herniation: A Single-Center Observational Study.

OBJECTIVE: To examine outcomes and complications following first-time lumbar microdiscectomy. METHODS: Prospective data for patients operated on between May 2007 and July 2016 were obtained from the Norwegian Registry for Spine Surgery. The primary outcome was change in Oswestry Disability Index (ODI) score at 1 year. Secondary endpoints were change in quality of life measured with EuroQol 5 Dimensions, back and leg pain measured with numeric rating scales, and perioperative complications within 3 months of surgery. RESULTS: For all enrolled patients (N = 1219) enrolled, mean improvement in ODI at 1 year was 33.3 points (95% confidence interval [CI] 31.7 to 34.9, P < 0.001). Mean improvement in EuroQol 5 Dimensions at 1 year of 0.52 point (95% CI 0.49 to 0.55, P < 0.001) represents a large effect size (Cohen's d = 1.6). Mean improvements in back pain and leg pain numeric rating scales were 3.9 points (95% CI 3.6 to 4.1, P < 0.001) and 5.0 points (95% CI 4.8 to 5.2, P < 0.001), respectively. There were 18 surgical complications in 1219 patients and 63 medical complications in 846 patients. The most common complication was micturition problems at 3 months following surgery (n = 25, 2.1%). In multivariate analysis, ODI scores of 21-40 (hazard ratio [HR] 14.5, 95% CI 1.1 to 27.9, P = 0.035), 41-60 (HR 27.5, 95% CI 13.4 to 41.7, P < 0.001), 61-80 (HR 47.4, 95% CI 33.4 to 61.4, P < 0.001) and >81 (HR 66.7, 95% CI 51.1 to 82.2, P < 0.001) were identified as positive predictors for ODI improvement at 1 year, whereas age ≥65 (HR -0.9, 95% CI -0.3 to -1.5, P = 0.004) was identified as a negative predictor for ODI improvement. CONCLUSIONS: Microdiscectomy for lumbar disc herniation is an effective and safe treatment.

Ocular angiostrongyliasis--first case report from Jamaica.

A 30-year-old female presented with a one-month history of blurred vision in her left eye. Examination revealed a live motile worm in the anterior chamber of the left eye. She also had retinal pigment epithelial disturbance with focal intraretinal haemorrhage. The 19.9 mm worm was surgically removed and identified as Angiostrongylus cantonesis. She was treated with oral mebendazole. Her vision improved from counting fingers in the left eye to 6/36. This is the first documented case of ocular angiostrongyliasis in Jamaica.

Lumbar Microdiscectomy in Obese Patients: A Multicenter Observational Study.

OBJECTIVE: To evaluate the association between obesity and outcomes after microdiscectomy for lumbar disc herniation. METHODS: The primary outcome measure was change in Oswestry Disability Index (ODI) at 1 year after surgery. Obesity was defined as body mass index (BMI) ≥30. Prospective data were retrieved from the Norwegian Registry for Spine Surgery. RESULTS: We enrolled 4932 patients, 4018 nonobese and 914 obese. For patients with complete 1-year follow-up (n = 3381) the mean improvement in ODI was 31.2 points (95% confidence interval 30.4-31.9, P < 0.001). Improvement in ODI was 31.4 points in nonobese and 30.1 points in obese patients (P = 0.182). Obese and nonobese patients were as likely to achieve a minimal clinically important difference (84.2 vs. 82.7%, P = 0.336) in ODI (≥10 points improvement). Obesity was identified as a negative predictor for ODI improvement in a multiple regression analysis (BMI 30-34.99; P < 0.001, BMI ≥35; P = 0.029). Obese and nonobese patients experienced similar improvement in Euro-Qol-5 scores (0.48 vs. 0.49 points, P = 0.441) as well as back pain (3.7 vs. 3.5 points, P = 0.167) and leg pain (4.7 vs. 4.8 points, P = 0.654), as measured by the Numeric Rating Scale. Duration of surgery was shorter for nonobese patients (55.7 vs. 65.3 minutes, P ≤ 0.001). Nonobese patients experienced fewer complications compared with obese patients (6.1% vs. 8.3%, P = 0.017). Obese patients had slightly longer hospital stays (2.0 vs. 1.8 days, P = 0.004). CONCLUSIONS: Although they had more minor complications, obese individuals experienced improvement after lumbar microdiscectomy for lumbar disc herniation similar to that of nonobese individuals.

Validation of intracranial hemorrhage in the Norwegian Patient Registry.

Objectives: Administrative health registries need to have accurate diagnoses and sufficient coverage in the population they serve in order to be useful in research. In this study, we investigated the proportion of discharge diagnoses of intracranial hemorrhage (ICH) that were coded correctly in the Norwegian Patient Registry (NPR). Materials and Methods: We reviewed the electronic medical records and diagnostic imaging of all admissions to St. Olavs University Hospital, Trondheim, Norway, between January 1, 2008, to December 31, 2014, with a discharge diagnosis of ICH in the NPR, and estimated positive predictive values (PPVs) for primary and secondary diagnoses. Separate calculations were made for inpatient and outpatient admissions. Results: In total, 1,419 patients with 1,458 discharge diagnoses of ICH were included in our study. Overall, 1,333 (91.4%) discharge diagnoses were coded correctly. For inpatient admissions, the PPVs for primary discharge codes were 96.9% for hemorrhagic stroke, 95.3% for subarachnoid hemorrhage, and 97.9% for subdural hemorrhage. The most common cause of incorrect diagnosis was previous stroke that should have been coded as rehabilitation or sequela after stroke. There were more false-positive diagnoses among outpatient consultations and secondary diagnoses. Conclusion: Coding of ICH discharge diagnoses in the NPR is of high quality, showing that data from this registry can safely be used for medical research.

Surgery for Herniated Lumbar Disc in Daily Tobacco Smokers: A Multicenter Observational Study.

OBJECTIVE: To compare clinical outcomes at 1 year following single-level lumbar microdiscectomy in daily tobacco smokers and nonsmokers. METHODS: Data were collected through the Norwegian Registry for Spine Surgery. The primary endpoint was a change in the Oswestry Disability Index (ODI) at 1 year. Secondary endpoints were change in quality of life measured with EuroQol 5 Dimensions (EQ-5D), leg and back pain measured with a numerical rating scale (NRS), and rates of surgical complications. RESULTS: A total of 5514 patients were enrolled, including 3907 nonsmokers and 1607 smokers. A significant improvement in ODI was observed for the entire cohort (mean, 31.1 points; 95% confidence interval [CI], 30.4-31.8; P < 0.001). Nonsmokers experienced a greater improvement in ODI at 1 year compared with smokers (mean, 4.1 points; 95% CI, 2.5-5.7; P < 0.001). Nonsmokers were more likely to achieve a minimal important change (MIC), defined as an ODI improvement of ≥10 points, compared with smokers (85.5% vs. 79.5%; P < 0.001). Nonsmokers experienced greater improvements in EQ-5D (mean difference, 0.068; 95% CI, 0.04-0.09; P < 0.001), back pain NRS (mean difference, 0.44; 95% CI, 0.21-0.66; P < 0.001), and leg pain NRS (mean difference, 0.54; 95% CI, 0.31-0.77; P < 0.001). There was no difference between smokers and nonsmokers in the overall complication rate (6.2% vs. 6.7%; P = 0.512). Smoking was identified as a negative predictor for ODI change in a multiple regression analysis (P < 0.001). CONCLUSIONS: Nonsmokers reported a greater improvement in ODI at 1 year following microdiscectomy, and smokers were less likely to experience an MIC. Nonetheless, significant improvement was also found among smokers.

Risk of intracranial hemorrhage (RICH) in users of oral antithrombotic drugs: Nationwide pharmacoepidemiological study.

BACKGROUND: The risks of intracranial haemorrhage (ICH) associated with antithrombotic drugs outside clinical trials are gaining increased attention. The aim of this nationwide study was to investigate the risk of ICH requiring hospital admission in users of antithrombotic drugs. METHODS AND FINDINGS: Data from the Norwegian Patient Registry and Norwegian Prescription Database were linked on an individual level. The primary outcome was incidence rates of ICH associated with use of antithrombotic drugs. Secondary endpoints were risk of ICH and fatal outcome following ICH assessed by Cox models. Among 3,131,270 individuals ≥18 years old observed from 2008 through 2014, there were 729,818 users of antithrombotic medications and 22,111 ICH hospitalizations. Annual crude ICH rates per 100 person-years were 0.076 (95% CI, 0.075-0.077) in non-users and 0.30 (95% CI, 0.30-0.31) in users of antithrombotic medication, with the highest age and sex adjusted rates observed for aspirin-dipyridamole plus clopidogrel (0.44; 95% CI, 0.19-0.69), rivaroxaban plus aspirin (0.36; 95% CI, 0.16-0.56), warfarin plus aspirin (0.34; 95% CI, 0.26-0.43), and warfarin plus aspirin and clopidogrel (0.33; 95% CI, 0.073-0.60). With no antithrombotic medication as reference, the highest adjusted hazard ratios (HR) for ICH were observed for aspirin-dypiridamole plus clopidogrel (6.29; 95% CI 3.71-10.7), warfarin plus aspirin and clopidogrel (4.38; 95% CI 2.71-7.09), rivaroxaban plus aspirin (3.82; 95% CI, 2.46-5.95), and warfarin plus aspirin (3.40; 95% CI, 2.99-3.86). All antithrombotic medication regimens were associated with an increased risk of ICH, except dabigatran monotherapy (HR 1.20; 95% CI, 0.88-1.65) and dabigatran plus aspirin (HR 1.79; 95% CI, 0.96-3.34). Fatal outcome within 90 days was more common in users (2,603 of 8,055) than non-users (3,228 of 14,056) of antithrombotic medication (32.3% vs 23.0%, p<0.001), and was associated with use of warfarin plus aspirin and clopidogrel (HR 2.89; 95% CI, 1.49-5.60), warfarin plus aspirin (HR 1.37; 95% CI, 1.11-1.68), aspirin plus clopidogrel (HR 1.30; 95% CI, 1.05-1.61), and warfarin (HR 1.19; 95% CI, 1.09-1.31). Increased one-year mortality was observed in users of antithrombotic medication following hemorrhagic stroke, subdural hemorrhage, subarachnoid hemorrhage, and traumatic ICH (all p<0.001). Limitations include those inherent to observational studies including the inability to make causal inferences, certain assumptions regarding drug exposure, and the possibility of residual confounding. CONCLUSIONS: The real-world incidence rates and risks of ICH were generally higher than reported in randomized controlled trials. There is still major room for improvement in terms of antithrombotic medication safety (clinicaltrials.gov NCT02481011).

Functional outcome and survival following spontaneous intracerebral hemorrhage: A retrospective population-based study.

BACKGROUND: Accurate and reliable clinical and radiological predictors of intracerebral hemorrhage (ICH) outcomes are needed to optimize treatment of ICH. The aim of this study was to investigate functional outcome and identify predictors of severe disability or death following ICH. MATERIALS AND METHODS: Retrospective population-based study of spontaneous ICH. Clinical and radiological data were obtained from electronic medical records, and functional outcome estimated using the modified Rankin Scale (mRS) before ICH and at 3 and 12 months after ICH. RESULTS: Four hundred and fifty-two patients were included (mean age 74.8 years, 45.6% females). Proportion of fatal outcome at 1 week was 22.1%, at 3 months 39.2%, and at 12 months 44.9%. Median mRS score before the ICH was 1 (interquartile range [IQR] 2); for survivors at 3 months, it was 5 (IQR 3); and at 12 months, it was 3 (IQR 2). Independent predictors of severe disability (mRS of 5) or death (mRS of 6) were use of oral antithrombotic drugs (OR 2.2, 95% CI 1.3-3.8, p = 0.04), mRS score before the ICH (OR 1.8, 95% CI 1.4-2.2, p < 0.001), Glasgow Coma Scale (GCS) on admission (OR 8.3, 95% CI 3.5-19.7, p < 0.001), hematoma volume >60 ml (OR 4.5, 05% CI 2.0-10.2, p < 0.001), and intraventricular hematoma extension (OR 1.8, 95% CI 0.8-4.2, p < 0.001). CONCLUSION: Intracerebral hemorrhage is associated with high mortality, and more than one third of survivors end up with severe disability or death 3 months later. Predictors of severe disability or death were use of oral antithrombotic drugs, functional disability prior to ICH, low GCS on admission, larger hematoma volume, and intraventricular hematoma extension.

Analyzing cytotoxic T lymphocyte activity: a simple and reliable flow cytometry-based assay.

A flow cytometry-based assay for analyzing cytotoxic T lymphocyte (CTL) activity is presented. This new approach is characterized by easy handling, the generation of highly reproducible data sets and is not dependent on the use of radioactivity. Before exposure to primed CTL effector cells the target cells were labeled with the green fluorescent dye DiO18(3) which is incorporated stably into the cell membrane. After a 4-h incubation period, samples were counterstained with the red fluorescent nuclear dye propidium iodide in order to permit discrimination between live and dead cells within both cell populations. The assay has been used to quantitate CTL effector activity against allogeneic lymphoblasts. Results derived from this novel flow cytometry assay show an excellent correlation (r = 0.988) with data obtained using the standard 51chromium release assay. An additional advantage of the assay is that freshly prepared splenocytes may be used as target cells because culturing and activation of target cells is no longer required. The results demonstrate that the fluorescent dyes DiO18(3) and propidium iodide in combination with flow cytometry permit accurate analysis of cytotoxic T cell activity.

20q13.2 amplification in intraductal hyperplasia adjacent to in situ and invasive ductal carcinoma of the breast.

The 20q13 region harboring recently described putative oncogenes is frequently amplified in invasive ductal carcinoma (IDC). The aim of this study was to examine the 20q13 copy number in intraduct hyperplasia (IH), atypical duct hyperplasia (ADH), and ductal carcinoma in situ (DCIS) adjacent to IDC. In 5 patients, comparative genomic hybridization (CGH) after laser microdissection revealed 20q13 amplification in four of five cases of IH, in all of three cases of IH with atypia, all five of DCIS, and all five of IDC. Fluorescence in situ hybridization (FISH) confirmed the amplification at 20q13.2 in IH in the two specimens analyzed. The amplification rate, however, was higher in DCIS and IDC. In phenotypically normal ductal epithelium normal values were found for 20q13 copy number by FISH (n=2) and CGH (n=5). Although the number of cases presented here is small, our results suggest that mutations in the 20q13.2 region in IH may be associated with accelerated proliferation and hyperplasia of the ductal epithelium. Progression to DCIS and ICD is accompanied by a further increase in the 20q13.2 copy number.

Accumulation of chromosomal imbalances from intraductal proliferative lesions to adjacent in situ and invasive ductal breast cancer.

Carcinoma of the breast is thought to evolve through a sequential progression from normal to proliferative epithelium and eventually into carcinoma. Here lumpectomy specimens from five patients were studied, selected for the presence of ductal hyperplasia without atypia, atypical ductal hyperplasia, ductal carcinoma in situ, and invasive ductal carcinoma. Laser microdissection of tissue allowed precise sampling and direct correlation of phenotypic and genotypic changes. Analyses of the samples revealed an increasing mean number of chromosomal changes occurring with increasing histologic severity, and for the first time chromosomal abnormalities were demonstrated in ductal hyperplasia without atypia. Chromosomal changes found in each of the four histologic entities included gains on 10q, 12q, 16p, and 20q and loss on 13q. In ductal hyperplasia without atypia, gain on 20q as well as loss on 13q was detected with high frequency (four of five samples). Alterations identified in more than 50% of atypical ductal hyperplasia samples included gains on 3p, 8q, 15q, and 22q and loss on 16q. In ductal carcinoma in situ, gain of DNA on 1q and 17q and loss on 4q were additionally found, and in invasive ductal carcinoma, further gains on 6p, 10q, 11q13, and 17p were identified. The chromosomal alterations occurring in the different histopathologic lesions strongly suggest that these regions harbor tumor suppressor genes or oncogenes significant for the development of ductal carcinoma of the breast.

Intratumoral heterogeneity in breast carcinoma revealed by laser-microdissection and comparative genomic hybridization.

To evaluate the potential cytogenetic heterogeneity in breast carcinoma, several small cell groups (each consisting of 20 to 50 cells) were investigated within paraffin sections. By laser-microdissection, three to seven cell groups were taken per case. The DNA was amplified by degenerate oligonucleotide primed PCR (DOP-PCR), and the samples were analyzed by CGH for chromosomal gains and losses. Two ductal invasive breast carcinomas, one of them with two lymphnode metastases, were investigated. To compare the results from the small samples, CGH was also performed on DNA isolated from the tumorous regions of three to five serial sections (10(7) to 10(6) cells). The aberrations observed in the microdissected tumor samples were multiple and involved up to 14 different chromosomal or subchromosomal regions. The most frequent changes were gains on chromosomes 12q (14/20) and 20q (16/20), and loss on 13q (12/20). Some aberrations have rarely been detected (e.g., loss on 2p, gain on 8q). Comparing chromosomal imbalances in primary tumors and lymph node metastases, more consistent changes were found between the primary tumor and its corresponding metastases than between both primary tumors. The laser-microdissected samples in general showed more chromosomal aberrations than DNA isolated from several tumor sections. Our CGH results were confirmed by fluorescence in situ hybridization (FISH) for the chromosomal regions of centromere 1 and 20, and 20q13. In addition, microsatellite analyses on 31 samples confirmed our CGH findings for selected chromosome regions 2p and 11q. It can be concluded that there is a distinct intratumoral heterogeneity in primary breast tumors as well as in the corresponding lymph node metastases. The combination of microdissection and CGH enabled us to detect cytogenetic aberrations from important clones which are missed when analyzing DNA extracted from large cell numbers.