MRD-Based Therapeutic Decisions in Genetically Defined Subsets of Adolescents and Young Adult Philadelphia-Negative ALL

Simple Summary

In acute lymphoblastic leukemia (ALL), once a complete remission is achieved following induction chemotherapy, the study of submicroscopic minimal residual disease (MRD) represents a highly sensitive tool to assess the efficacy of early chemotherapy courses and predict outcome. Because of the significant therapeutic progress occurred in adolescent and young adult (AYA) ALL, the importance of MRD in this peculiar age setting has grown considerably, to refine individual prognostic scores within different genetic subsets and support specific risk and MRD-oriented programs. The evidence coming from the most recent MRD-based studies and the new therapeutic directions for AYA ALL are critically reviewed according to ALL subset and risk category.

Abstract

In many clinical studies published over the past 20 years, adolescents and young adults (AYA) with Philadelphia chromosome negative acute lymphoblastic leukemia (Ph− ALL) were considered as a rather homogeneous clinico-prognostic group of patients suitable to receive intensive pediatric-like regimens with an improved outcome compared with the use of traditional adult ALL protocols. The AYA group was defined in most studies by an age range of 18–40 years, with some exceptions (up to 45 years). The experience collected in pediatric ALL with the study of post-induction minimal residual disease (MRD) was rapidly duplicated in AYA ALL, making MRD a widely accepted key factor for risk stratification and risk-oriented therapy with or without allogeneic stem cell transplantation and experimental new drugs for patients with MRD detectable after highly intensive chemotherapy. This combined strategy has resulted in long-term survival rates of AYA patients of 60–80%. The present review examines the evidence for MRD-guided therapies in AYA’s Ph− ALL, provides a critical appraisal of current treatment pitfalls and illustrates the ways of achieving further therapeutic improvement according to the massive knowledge recently generated in the field of ALL biology and MRD/risk/subset-specific therapy

Relevance of antiphospholipid antibody profile in the clinical outcome of ITP: a single-centre study

OBJECTIVES

The relevance of detecting antibodies against anticardiolipin, β2-glycoprotein I (β2gpI) or lupus anticoagulant (LA), collectively called antiphospholipid autoantibodies (APA), in subjects with immune thrombocytopenia (ITP) is still a debated issue. In particular, whether APA profile may affect the clinical course of ITP is unknown.

METHODS

In this study, we report our experience in a cohort of ITP patients with APA with specific interest to the relevance of different antiphospholipid antibody profiles in clinical outcome and response to treatment.

RESULTS

Thirty-seven out of 159 patients (23.2%) fulfilling ITP criteria had a platelet count ≤50 × 10⁹/L and tested positive at APA at ITP onset. Twenty-three (62.1%) patients received at least one line of treatment for ITP. Fourteen subjects (37.8%) showing triple positivity for APA showed a significantly lower median platelet count compared to other APA patients (p = .006). Among these ITP subjects with triple positivity, 85.7% needed a treatment because of low platelet count compared to 47.8% ITP patients with non-triple-positive APA (p = .0094). ITP/APA subjects who received immunosuppressors had a higher rate of thrombosis (p = .024) as well as thrombosis developed in subjects who were on steroid therapy at a significantly higher dosage than subjects who did not develop thrombotic episodes (p < .001). When considering treatment, CR and SR rate were significantly higher in ITP/triple-positive patients compared to non-triple-positive subjects (p = .021 and p = .005).

CONCLUSIONS

The profile of APA may affect the outcome of patients with ITP.

Safety and efficacy of switching from branded to generic imatinib in chronic phase chronic myeloid leukemia patients treated in Italy

The use of generic drugs after patent expiration of their originators is a relative novelty in the treatment of chronic cancer patients in Western countries. In this observational study we analyzed a cohort of 294 Italian chronic phase chronic myeloid leukemia patients treated frontline with branded imatinib (Glivec®) for at least 6 months and then uniformly switched to generic imatinib upon requirement of health authorities in early 2017. Median age at diagnosis was 57 years (range 19-87). Sokal risk was low/intermediate/high in 55%, 32% and 8% of cases, respectively. Median duration of branded imatinib treatment was 7.4 years (range 0.5-16.7). At a median follow-up of 7.5 months after switch to generic imatinib, 17% of patients reported new or worsening side effects, but grade 3-4 non-hematological adverse events were rare. Six patients switched back to branded imatinib, with improvement in the side effect profile, and 4 pts moved to bosutinib or nilotinib for resistance/intolerance. The majority of patients were in major (26%) or deep molecular response (66%) at the time of switch. Molecular responses remained stable, improved or worsened in 61%, 25% and 14% of patients, respectively. We conclude that switch to generic imatinib for patients who have been receiving branded imatinib appears to be effective and safe. Molecular responses may continue to improve over time. Some patients experienced new or worsened side effects but less than 5% of the whole cohort needed to switch back to branded imatinib or move to other treatments. Savings were around 3 million Euros.

Excellent outcomes of 2G-TKI therapy after imatinib failure in chronic phase CML patients

Second-generation tyrosine kinase inhibitors (2G-TKIs) dasatinib and nilotinib produced historical rates of about 50% complete cytogenetic response (CCyR) and about 40% major molecular response (MMR) in chronic myeloid leukaemia (CML) patients failing imatinib. Direct comparisons between dasatinib and nilotinib are lacking, and few studies addressed the dynamics of deep molecular response (DMR) in a "real-life" setting. We retrospectively analyzed 163 patients receiving dasatinib (n = 95) or nilotinib (n = 68) as second-line therapy after imatinib. The two cohorts were comparable for disease's characteristics, although there was a higher rate of dasatinib use in imatinib-resistant and of nilotinib in intolerant patients. Overall, 75% patients not in CCyR and 60% patients not in MMR at 2G-TKI start attained this response. DMR was achieved by 61 patients (37.4%), with estimated rate of stable DMR at 5 years of 24%. After a median follow-up of 48 months, 60% of patients persisted on their second-line treatment. Rates and kinetics of cytogenetic and molecular responses, progression-free and overall survival were similar for dasatinib and nilotinib. In a "real-life" setting, dasatinib and nilotinib resulted equally effective and safe after imatinib failure, determining high rates of CCyR and MMR, and a significant chance of stable DMR, a prerequisite for treatment discontinuation.

Pharmacokinetics and Pharmacodynamics of Melagatran, a Novel Synthetic LMW Thrombin Inhibitor, in Patients with Acute DVT

Forty-eight patients with acute proximal deep vein thrombosis (DVT) were randomised to intravenous infusions for 4 to 6 days with melagatran, a novel synthetic low molecular weight thrombin inhibitor, or unfractionated heparin adjusted by the activated partial thromboplastin time (APTT). The aim of the study was to investigate the pharmacokinetics, pharmacodynamics and the safety of melagatran therapy at three different doses. Steady-state plasma concentrations were rapidly achieved and maintained throughout the infusion period. The mean plasma concentrations in the low, medium and high dose groups were 0.17, 0.31 and 0.53 μmol/l, respectively. The prolongation of APTT was stable during the melagatran infusions and correlated to the plasma concentration. Phlebographically verified regression of thrombus size measured as decrease in Marder score was seen after 4 to 6 days in 8 of 12 patients, 6 of 12 patients and 5 of 11 patients in the low, medium and high dose groups of melagatran and in 5 of the heparin-treated patients. In the low dose group with melagatran, thrombus extension was seen in one patient. At the dose levels studied, melagatran was well tolerated with no clinically significant bleeding problems, suggesting that melagatran could safely be given to patients suffering from DVT.

Factor V Leiden (G1691A) and Prothrombin Gene G20210A Mutations as Potential Risk Factors for Venous Thromboembolism after Total Hip or Total Knee Replacement Surgery

Patients (n = 1600) from 12 European countries, scheduled for elective orthopaedic hip or knee surgery, were screened for Factor V Leiden and prothrombin gene G20210A mutations, found in 5.5% and 2.9% of the populations, respectively. All patients underwent prophylactic treatment with one of four doses of melagatran and ximelagatran or dalteparin, starting pre-operatively. Bilateral ascending venography was performed on study day 8-11. The patients were subsequently treated according to local routines and followed for 4-6 weeks postoperatively. The composite endpoint of screened deep vein thrombosis (DVT) and symptomatic pulmonary embolism (PE) during prophylaxis did not differ significantly between patients with or without these mutations. Symptomatic venous thromboembolism (VTE) during prophylaxis and follow-up (1.9%) was significantly over-represented among patients with the prothrombin gene G20210A mutation (p = 0.0002). A tendency towards increased risk of VTE was found with the Factor V Leiden mutation (p = 0.09). PE were few, but significantly over-represented in both the Factor V Leiden and prothrombin gene G20210A mutated patients (p = 0.03 and p = 0.05, respectively). However, since 90% of the patients with these genetic risk factors will not suffer a VTE event, a general pre-operative genotyping is, in our opinion, of questionable value.

Effects of recombinant human prothrombin on thrombin generation in plasma from patients with hemophilia A and B

BACKGROUND

The present study was carried out to investigate the impact of FII levels, and their increase, on the hemostatic potential in plasma from hemophilia A and B patients with and without inhibitors.

METHOD

Recombinant human factor (F) II (rhFII) was added ex vivo to plasma from 68 patients with hemophilia A and B, with or without inhibitors. The hemostatic potential as measured by thrombin generation (calibrated automated thrombogram [CAT]) was focused on the endogenous thrombin potential (ETP) as it has been shown to correlate with the clinical phenotype of bleeding in hemophilia patients and has also been used to guide bypassing therapy in hemophilia patients with inhibitors before elective surgery. The factor eight inhibitor bypassing agent (FEIBA(®) ) was used as a reference to the clinical situation.

RESULTS

The study shows that rhFII concentration-dependently increased ETP by a similar magnitude in hemophilia A and B, both with and without inhibitors. Compared with FEIBA, rhFII showed a shallower concentration-response curve. In both types of hemophilia 100 mg L(-1) of rhFII roughly doubled the ETP. A corresponding response was obtained by 0.5 U mL(-1) of FEIBA.

CONCLUSION

These data support the theory that FII is one of the major components responsible for the efficacy of FEIBA. The data also indicate that rhFII may be useful, alone or in combination with other coagulation factors, in some of the conditions for which FEIBA is used today, although more data are needed to substantiate this.

Reproducibility of three-dimensional cephalometric landmarks in cone-beam and low-dose computed tomography

OBJECTIVES

The purpose of this study is to compare the reproducibility of three-dimensional cephalometric landmarks on three-dimensional computed tomography (3D-CT) surface rendering using clinical protocols based on low-dose (35-mAs) spiral CT and cone-beam CT (I-CAT). The absorbed dose levels for radiosensitive organs in the maxillofacial region during exposure in both 3D-CT protocols were also assessed.

MATERIALS AND METHODS

The study population consisted of ten human dry skulls examined with low-dose CT and cone-beam CT. Two independent observers identified 24 cephalometric anatomic landmarks at 13 sites on the 3D-CT surface renderings using both protocols, with each observer repeating the identification 1 month later. A total of 1,920 imaging measurements were performed. Thermoluminescent dosimeters were placed at six sites around the thyroid gland, the submandibular glands, and the eyes in an Alderson phantom to measure the absorbed dose levels.

RESULTS

When comparing low-dose CT and cone-beam CT protocols, the cone-beam CT protocol proved to be significantly more reproducible for four of the 13 anatomical sites. There was no significant difference between the protocols for the other nine anatomical sites. Both low-dose and cone-beam CT protocols were equivalent in dose absorption to the eyes and submandibular glands. However, thyroid glands were more irradiated with low-dose CT.

CONCLUSIONS

Cone-beam CT was more reproducible and procured less irradiation to the thyroid gland than low-dose CT.

CLINICAL RELEVANCE

Cone-beam CT should be preferred over low-dose CT for developing three-dimensional bony cephalometric analyses.

[Management of plexiform neurofibroma isolated in childhood: four patients]

Plexiform neurofibroma is a rare and benign tumor often associated with type 1 neurofibromatosis (NF1) or Von Recklinghausen's disease. Present in one third of cases of NF1, there are isolated forms where the diagnosis should remain a diagnosis of exclusion. We report four cases of isolated plexiform neurofibromas found in children from topographies and we discuss the pretherapeutic assessment, the surgical management and the long-term follow-up.

[Validating a loading protocol for weakened mandibular models]

INTRODUCTION

The purpose of this study was to validate an experimental model of weakened synthetic mandible loaded in a device simulating masticatory forces by studying the reproducibility of the fracture threshold.

MATERIALS AND METHODS

Both sides of five synthetic mandibles were weakened by progressive synthetic bone resection. The synthetic mandibles were submitted, after each resection, to static chewing exercises in the simulator. The threshold fracture was recorded.

RESULTS

The fracture threshold mean resection height was 19.33 mm with a percentage of error of 6.72%.

DISCUSSION

The low percentage of error allowed us to validate this experimental model. A comparison with other experimental or finite element models confirmed our protocol and results. We plan to apply this protocol to fresh weakened mandibles.

Stroke event rates in anticoagulated patients with paroxysmal atrial fibrillation

AIMS

To test the hypothesis that stroke and systemic embolic events (SEE) in the stroke prevention using an oral thrombin inhibitor in atrial fibrillation (SPORTIF) III and V trials are different between paroxysmal and persistent atrial fibrillation (AF).

METHODS

Data analysis from two cohorts of patients enrolled in the prospective SPORTIF III and V clinical trials (n = 7329); 836 subjects (11.4%) with paroxysmal AF [mean age 70.1 years (SD = 9.5)] were compared with 6493 subjects with persistent AF for this ancillary study.

RESULTS

The annual event rates for stroke/SEE are 1.73% for persistent AF and 0.93% for paroxysmal AF. In a multivariate analysis, after adjusting for stroke risk factors, gender and aspirin usage, the differences remained statistically significant with a higher hazard ratio (HR) for stroke/SEE in persistent AF [vs. paroxysmal AF, HR 1.87, 95% confidence interval (CI) 1.04-3.36; P = 0.037]. In 'high risk' patients (with >or=2 stroke risk factors) annual event rates for stroke/SEE were 2.08% for persistent AF and 1.27% for paroxysmal AF (adjusted HR = 1.68, 95% CI 0.91-3.1, P = 0.098). Elderly patients had annual event rates for stroke/SEE of 2.38% for persistent AF and 1.13% for paroxysmal AF (adjusted HR = 2.27, 95% CI 0.92-5.59, P = 0.075). Vitamin K antagonist (VKA)-naive paroxysmal AF patients had a 1.89%/year stroke/SEE rate, compared with 0.61% for previous VKA takers (HR = 0.33, 95% CI 0.11-1.01, P = 0.052).

CONCLUSION

In this large clinical trial cohort of anticoagulated AF patients, those with paroxysmal AF had stroke rates which were lower than for patients with persistent AF, although both groups had broadly similar stroke risk factors. Subjects with paroxysmal AF at 'high risk' had stroke/SEE rates that were not significantly different to persistent AF subjects.

Angiotensin converting enzyme inhibitor and angiotensin receptor blockade use in relation to outcomes in anticoagulated patients with atrial fibrillation

BACKGROUND

The renin-angiotensin-aldosterone-system (RAAS) plays an important role in atrial fibrillation (AF). Evidence shows that blocking the RAAS with angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) has a definite role in preventing new onset AF and in maintaining sinus rhythm in recurrent AF. Our aim was to determine if ACEI/ARB treatment was associated with clinical outcomes [stroke/systemic embolic events (SEE), mortality] in a controlled, anticoagulated AF population.

METHODS

An ancillary retrospective cross-sectional and longitudinal analysis of participants in the Stroke Prevention using an ORal Thrombin Inhibitor in AF (SPORTIF) III and V trials, in relation to use (or nonuse) of ACEI/ARBs.

RESULTS

Rates of stroke/SEEs, mortality or major bleeding were no different between users and nonusers in the whole cohort, or in relation to the presence/absence of hypertension, coronary artery disease and previous stroke/transient ischaemic attack, nor amongst those aged <75 years. Patients aged > or = 75 years taking ACEIs or ARBs had lower mortality (HR 0.71, 95% CI 0.52-0.95), but no significant influence on other end-points was noted. Diabetics and those with left ventricular dysfunction on ximelagatran had a higher odds ratio of abnormal liver enzyme levels. There was no apparent benefit of ACEIs or ARBs on other event rates.

CONCLUSIONS

This analysis from two large randomized trials of anticoagulation has not demonstrated a significant benefit of ACEI or ARB use amongst AF patients, except amongst elderly subjects.

A randomized, controlled, dose-guiding study of the oral direct thrombin inhibitor ximelagatran compared with standard therapy for the treatment of acute deep vein thrombosis: THRIVE I

This randomized, controlled, multicentre study evaluated the efficacy and tolerability of the oral direct thrombin inhibitor ximelagatran, compared with a low-molecular-weight heparin (dalteparin) followed by warfarin, in the treatment of deep vein thrombosis (DVT) of the lower extremity. Patients with acute DVT received oral ximelagatran (24, 36, 48 or 60 mg twice daily) or dalteparin and warfarin for 2 weeks. Evaluation of paired venograms from 295 of 350 patients showed regression of the thrombus in 69% of patients treated with ximelagatran and 69% of patients treated with dalteparin and warfarin. Progression was observed in 8% and 3% of patients, respectively. Changes in thrombus size according to the Marder score were similar in all groups. Treatment discontinuation due to bleeding occurred in two patients receiving ximelagatran (24- and 36-mg groups) and in two patients receiving dalteparin and warfarin. Reduction in pain, edema and circumference of the affected leg was similar in all groups. Oral ximelagatran appears to be a promising alternative to current anticoagulant therapy to limit the progression of acute DVT, and it seems to possess a wide therapeutic window.

Factor V Leiden (G1691A) and prothrombin gene G20210A mutations as potential risk factors for venous thromboembolism after total hip or total knee replacement surgery

Patients (n = 1600) from 12 European countries, scheduled for elective orthopaedic hip or knee surgery, were screened for Factor V Leiden and prothrombin gene G20210A mutations, found in 5.5% and 2.9% of the populations, respectively. All patients underwent prophylactic treatment with one of four doses of melagatran and ximelagatran or dalteparin, starting pre-operatively. Bilateral ascending venography was performed on study day 8-11. The patients were subsequently treated according to local routines and followed for 4-6 weeks postoperatively. The composite endpoint of screened deep vein thrombosis (DVT) and symptomatic pulmonary embolism (PE) during prophylaxis did not differ significantly between patients with or without these mutations. Symptomatic venous thromboembolism (VTE) during prophylaxis and follow-up (1.9%) was significantly over-represented among patients with the prothrombin gene G20210A mutation (p = 0.0002). A tendency towards increased risk of VTE was found with the Factor V Leiden mutation (p = 0.09). PE were few, but significantly over-represented in both the Factor V Leiden and prothrombin gene G20210A mutated patients (p = 0.03 and p = 0.05, respectively). However, since 90% of the patients with these genetic risk factors will not suffer a VTE event, a general pre-operative genotyping is, in our opinion, of questionable value.

Omeprazole and ranitidine in the prevention of relapse in patients with duodenal ulcer disease

BACKGROUND

Although the eradication of Helicobacter pylori is of primary importance when initiating treatment, it is also important to have a strategy for patients who are H pylori-negative, fail to demonstrate eradication or have a tendency to become re-infected or relapse.

PATIENTS AND METHODS

In a double-blind, parallel-group clinical trial of 928 patients (from 70 centres in 16 countries) with duodenal ulcers who after a short term study had relief of symptoms and healed ulcers proved endoscopically, 308 were randomly assigned to receive omeprazole 10 mg in the morning, 308 to receive omeprazole 20 mg in the morning and 312 to receive ranitidine 150 mg at bedtime for up to 12 months. Symptoms were assessed every three months and endoscopy repeated at three, six and 12 months, or more often if indicated by recurrence of symptoms. The safety screening included basal serum gastrin concentrations and gastric mucosal histopathology.

RESULTS

The remission rates up to 12 months were 87% for the omeprazole 20 mg group, 71% for the omeprazole 10 mg group and 63% for the ranitidine group. Omeprazole 20 mg differed significantly from both omeprazole 10 mg (P=0.0001, 95% CI 9 to 23) and ranitidine (P=0.0001, 95% CI 17 to 31). There was no statistically significant difference between omeprazole 10 mg and ranitidine over the 12-month period, but the 95% confidence interval allowed differences between 0% and 16% in favour of omeprazole at 12 months. A Cox regression analysis revealed that longer treatment courses to heal, smoking, a long ulcer history and young age negatively contributed to the odds of staying in remission. The treatments were well tolerated. There was a slight increase in basal serum gastrin concentrations, reflecting the different degrees of acid inhibition induced by the three treatments. No dysplastic or neoplastic lesions were found in any biopsies.

CONCLUSIONS

More duodenal ulcer patients are maintained in remission with omeprazole 20 mg daily than with omeprazole 10 mg daily or with ranitidine 150 mg at bedtime.

Pharmacokinetics and pharmacodynamics of melagatran, a novel synthetic LMW thrombin inhibitor, in patients with acute DVT

Forty-eight patients with acute proximal deep vein thrombosis (DVT) were randomised to intravenous infusions for 4 to 6 days with melagatran, a novel synthetic low molecular weight thrombin inhibitor, or unfractionated heparin adjusted by the activated partial thromboplastin time (APTT). The aim of the study was to investigate the pharmacokinetics, pharmacodynamics and the safety of melagatran therapy at three different doses. Steady-state plasma concentrations were rapidly achieved and maintained throughout the infusion period. The mean plasma concentrations in the low, medium and high dose groups were 0.17, 0.31 and 0.53 micromol/l, respectively. The prolongation of APTT was stable during the melagatran infusions and correlated to the plasma concentration. Phlebographically verified regression of thrombus size measured as decrease in Marder score was seen after 4 to 6 days in 8 of 12 patients, 6 of 12 patients and 5 of 11 patients in the low, medium and high dose groups of melagatran and in 5 of the heparin-treated patients. In the low dose group with melagatran, thrombus extension was seen in one patient. At the dose levels studied, melagatran was well tolerated with no clinically significant bleeding problems, suggesting that melagatran could safely be given to patients suffering from DVT.

Prognostic factors influencing relapse of oesophagitis during maintenance therapy with antisecretory drugs: a meta-analysis of long-term omeprazole trials

BACKGROUND

This meta-analysis investigated factors that may affect the risk of relapse of oesophagitis, and evaluated the predictive value of symptoms for the presence of relapse during long-term treatment.

METHODS

Individual data from 1154 patients included in five independently conducted, randomized, long-term clinical trials of the efficacy of different dosage regimens of omeprazole, standard ranitidine treatment and placebo for the prevention of relapse of oesophagitis were pooled for this meta-analysis. The therapeutic regimens studied were omeprazole 20 mg o.m. (OME20) in 366 patients, omeprazole 10 mg o.m. (OME10) in 225 patients, omeprazole 20 mg weekends (OMEW) in 235 patients, ranitidine 150 mg b.d. (RAN) in 179 patients, or placebo (PLA) in 149 patients.

RESULTS

OME20 maintained 82.4% (95% CI: 78.2-86.6%) of patients in endoscopic remission over the 6-month period compared to 71.9% (95% CI: 65.5-78.3%) for OME10, 52.3% (95% CI: 44.4-60.1%) for RAN, 42.7% (95% CI: 35.8-49.5%) for OMEW, and 10.6% (95% CI: 5.0-16.3%) for PLA. A Cox's regression analysis of time to recurrence of oesophagitis showed that four factors were associated with a higher relapse rate during placebo and active maintenance therapy: (a) pre-treatment severity of oesophagitis (P < 0.0001), (b) young age (P = 0.01), (c) non-smoking (P = 0.02) and (d) moderate/severe regurgitation before entry into the trials (P = 0.03). Asymptomatic relapse of oesophagitis was uncommon, being found in only 8.6% of the patients.

CONCLUSIONS

Maintenance treatment with omeprazole 10 and 20 mg daily is superior to all other regimens tested, and is only marginally influenced by the pretreatment severity of oesophagitis. Age contributes to the factors that influence the outcome during long-term treatment with omeprazole. Symptom relief is highly predictive for the maintenance of healing.

Repeated measures in clinical trials: analysis using mean summary statistics and its implications for design

This paper explores the use of simple summary statistics for analysing repeated measurements in randomized clinical trials with two treatments. Quite often the data for each patient may be effectively summarized by a pre-treatment mean and a post-treatment mean. Analysis of covariance is the method of choice and its superiority over analysis of post-treatment means or analysis of mean changes is quantified, as regards both reduced variance and avoidance of bias, using a simple model for the covariance structure between time points. Quantitative consideration is also given to practical issues in the design of repeated measures studies: the merits of having more than one pre-treatment measurement are demonstrated, and methods for determining sample sizes in repeated measures designs are provided. Several examples from clinical trials are presented, and broad practical recommendations are made. The examples support the value of the compound symmetry assumption as a realistic simplification in quantitative planning of repeated measures trials. The analysis using summary statistics makes no such assumption. However, allowance in design for alternative non-equal correlation structures can and should be made when necessary.

Endometriosis: studies of a method for the design of a surgical staging system

This study develops a method of identifying factors that predict pregnancy rates in patients with endometriosis. In 123 women, 60% had adhesions, 89% had implants, and 29% had endometriomas. The most common lesions were cul-de-sac implants (60%), ovarian implants (58%), and ovarian adhesions (55%). With no treatment, the life-table-estimated 3-year pregnancy rate was 40%; with oral contraceptives, 33%; and with surgery, 53%. Clustering techniques suggested new combinations of variables to be tested. We identified structures commonly involved simultaneously in a given patient, defined subgroups based on type of lesion, and developed a method to determine which factors were important in predicting outcome. In our patients, neither of two current methods of endometriosis staging predicted outcome. Further testing of the model systems suggested by the data may enable us to develop a staging system more predictive of pregnancy rates in endometriosis patients.