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PubMed2002

Prostate cancer trends in the era of prostate-specific antigen. An update of incidence, mortality, and clinical factors from the SEER database.

Concurrent with the successful life-saving efforts in terms of prostate cancer diagnosis and treatment, some men who do not need treatment are receiving it. These are men destined to die of causes other than prostate cancer. Unfortunately, at diagnosis, men needing treatment for prostate cancer cannot be differentiated from men who do not. To make such decisions correctly for individual patients would require extremely precise measures of the time to death from prostate cancer versus when the patient would die from a competing cause. Predictive tools with this level of accuracy will never be available given the inherent uncertainty of life. At the time of prostate cancer diagnosis, the date and the cause of death for the patient are matters of weak statistical speculation. Unless the date of death from prostate cancer and the date of death from non-prostate cancer causes can be precisely determined for each patient, some men will always be overtreated or undertreated. Conservative strategies result in the undertreatment of some patients who would benefit from treatment while sparing other patients unneeded treatment. Aggressive strategies result in the overtreatment of patients who do not need therapy while curing other men of prostate cancer. Both strategies are correct, but only some of the time. Better methods of determining the length of life and cause of death may improve this situation, but not by much. [figure: see text] Dramatic shifts in the incidence, grade, stage, and age of men with prostate cancer have been observed with the advent of widespread PSA-based cancer detection in the United States. Grade and stage trends suggest that more biologically relevant (the shift from well-differentiated to moderately differentiated tumors) and yet therapeutically amenable (earlier stage) tumors have been identified in large numbers of patients during the PSA era. Clearly many men have been diagnosed and treated who will not benefit from such treatment. The relative mix of these two groups of men is not known. Given the long delay between treatment and mortality that is inherent in prostate cancer (Fig. 14), the full effects of treatment on prostate cancer mortality are probably not yet seen in prostate cancer mortality data.

Age Factors↗

PubMed1997

Combined androgen blockade: the gold standard for metastatic prostate cancer.

There is no debate that both the earlier diagnosis and the treatment of men with cancer of the prostate (CaP) are having an impact on patients with this disease. In many practices there are fewer and fewer patients presenting with the classic diagnosis of 'advanced disease', i.e., stage M (D2). Only a few years ago, a large percentage of men with CaP had bony metastases when they presented to a physician. Hormonal ablation was the optimal treatment, and the only question was whether bilateral orchiectomy or medical castration should be used. The median time to progression with either type of monotherapy was 12-18 months, and the median time to survival was 24-36 months. Unfortunately, in many parts of the world, this scenario is still the norm. In the United States, Europe, and an increasing number of other countries, improved methods of detection with transrectal ultrasound and prostate-specific antigen (PSA) have resulted in a dramatic shift in the stage of disease at diagnosis. It is safe to say that in these countries the majority of prostate cancers are now being clinically diagnosed while still localized, and many organ-confined tumors are being definitively treated and cured. Nevertheless, many of these patients will be understaged at the time of diagnosis and will show progression following definitive therapy. In most surgical series approximately one half of patients will be found on pathologic examination to have pT3 disease. The use of PSA in the diagnosis of CaP has been mentioned, and it is being used extensively to monitor recurrent/residual disease. Hormonal therapy is being employed earlier in numerous clinical situations, and its use is no longer reserved solely for patients with metastatic disease. In this context combined androgen blockade has become the gold standard of treatment in neoadjuvant situations as well as for advanced CaP. Newer advances, including 3-month depot formulations of luteinizing hormone-releasing hormone analogues, the reversibility of medical castration, the preference of most patients to have medical castration, and the approval of other antiandrogens in the United States, all have further strengthened the use of combined androgen blockade. Hormonal therapy in adjuvant settings, when there is a high likelihood of disease recurrence, is also being used in many clinical situations. In addition, there appears to be a role for certain types of hormonal therapy in chemoprevention.

Androgen Antagonists↗

PubMed2002

[Narcotrend stages and end-tidal desflurane concentrations. An investigation during recovery from desflurane/remifentanil anaesthesia].

OBJECTIVE: [corrected] As indicated by the manufacturer the EEG monitor Narcotrend trade mark (MonitorTechnik, Bad Bramstedt) can be used to analyse EEG effects of volatile anaesthetics, however, published data are missing. This study evaluated the emergence from a desflurane/remifentanil anaesthetic and was designed to investigate the relationship between Narcotrend stages (version 2.0 AF) and end-tidal desflurane concentrations and to identify the pattern of changes of the Narcotrend stages during recovery. METHODS: Adult patients scheduled for orthopaedic surgery were premedicated with 0.15 mg/kg diazepam orally in the evening and on the morning before surgery. Narcotrend EEG electrodes were positioned on the patient's forehead as recommended by the manufacturer. For induction of anaesthesia, remifentanil was infused at 0.4 microgram/kg/min and propofol 2 mg/kg was given for hypnosis. After neuromuscular blockade and orotracheal intubation, remifentanil was reduced to 0.2 microgram/kg/min, and desflurane in O(2)/air was added according to clinical needs. After termination of surgery, administration of anaesthetics was discontinued and simultaneously, the fresh gas flow was increased to 10 l/min of O(2) while the respirator pattern was left unchanged. Narcotrend stages and end-tidal desflurane concentrations were recorded as data pairs at intervals of 1 min during emergence from anaesthesia; data evaluation included the last 7 min before extubation. RESULTS: A total of 50 patients (mean age +/-SD 44.4+/-13.0 years) were studied and 400 data pairs were obtained. A decreasing depth of anaesthesia as indicated by the Narcotrend was associated with significantly lower end-tidal desflurane concentrations: for E (general anaesthesia with deep hypnosis) 3.6+/-1.0 vol%, for D (general anaesthesia) 1.7+/-0.8 vol%, for C (light anaesthesia) 0.7+/-0.3 vol% and for A and B (awake or sedated) 0.5 vol%. A reduction of end-tidal desflurane concentrations was accompanied by a shift of Narcotrend stages from C/D/E to A/B/C. CONCLUSION: During emergence from desflurane/remifentanil anaesthesia, a reduction of end-tidal desflurane concentrations was detected by the EEG monitor Narcotrend and classified as a typical change of distribution of Narcotrend stages.

Adult↗

PubMed2005

Brain shift estimation in image-guided neurosurgery using 3-D ultrasound.

Intraoperative brain deformation is one of the most important causes affecting the overall accuracy of image-guided neurosurgical procedures. One option for correcting for this deformation is to acquire three-dimensional (3-D) ultrasound data during the operation and use this data to update the information provided by the preoperatively acquired MR data. For 12 patients 3-D ultrasound images have been reconstructed from freehand sweeps acquired during neurosurgical procedures. Ultrasound data acquired prior to and after opening the dura, but prior to surgery, have been quantitatively compared to the preoperatively acquired MR data to estimate the rigid component of brain shift at the first stages of surgery. Prior to opening the dura the average brain shift measured was 3.0 mm parallel to the direction of gravity, with a maximum of 7.5 mm, and 3.9 mm perpendicular to the direction of gravity, with a maximum of 8.2 mm. After opening the dura the shift increased on average 0.2 mm parallel to the direction of gravity and 1.4 mm perpendicular to the direction of gravity. Brain shift can be detected by acquiring 3-D ultrasound data during image-guided neurosurgery. Therefore, it can be used as a basis for correcting image data and preoperative planning for intraoperative deformations.

Algorithms↗

PubMed1984

Increasing incidence and constant mortality rates of breast cancer: time trends in Stockholm County 1961-1973.

This study describes trends in breast cancer incidence and survival in Stockholm County during 1961-1973. A discrepancy between increasing incidence and constant mortality rates was reflected in a significantly improved survival of the more recently treated patients. However, no change in survival was found when the patients were classified by axillary node status. The improvement thus seemed entirely the result of a more favorable stage distribution. The shift towards less advanced tumors was mainly caused by an increased age-standardized incidence of node-negative tumors, whereas the incidence of more advanced tumors seemed relatively unchanged. The survival from first distant metastasis was significantly increased; the use of combination chemotherapy might have contributed to this. The increase, however, was only moderate and did not seem to have contributed much to the improved overall survival. It is concluded that several confounding factors must be recognized when time trends in breast cancer are analyzed. A straightforward interpretation of observed changes is therefore not always possible. An increasing detection of tumors with relatively benign biological properties or lead time bias may well contribute to seemingly improved results.

Breast Neoplasms↗

PubMed2000

Incidental prostatic adenocarcinomas and putative premalignant lesions in TURP specimens collected before and after the introduction of prostrate-specific antigen screening.

BACKGROUND: Since the introduction of prostate-specific antigen (PSA) screening for the detection of prostatic adenocarcinoma (PCA), there has been an increase in the incidence of stage T1c PCA. The purpose of this study was to compare the frequency of incidental PCA found in transurethral resection of prostate (TURP) specimens for a 14-month period during 1989-1990 (before PSA screening was available) with the incidence of PCA for a 32-month period during 1997-1999 (after PSA screening became available). DESIGN: Consecutive TURP specimens from the 2 time periods were reviewed to identify incidental PCA, prostatic intraepithelial neoplasia (PIN), and atypical adenomatous hyperplasia (AAH). Cases of TURP for palliative treatment of known advanced PCA were excluded from the study. All TURP specimens were fixed in 10% buffered formalin and were processed according to the same protocol. RESULTS: We reviewed 533 and 449 TURP specimens for the time periods 1989-1990 and 1997-1999, respectively. Comparison of the results for these 2 time periods revealed that the combined prevalence of T1a and T1b PCA decreased over time from 12.9% to 8.0% (P =.06) with the introduction of PSA screening. A new group of T1c PCA was established in the post-PSA screening period of 1997-1999. There were no statistically significant differences in the incidences of T1a PCA, PIN, and AAH in TURP specimens for the 2 time periods. CONCLUSION: The decreased incidence of T1b PCA in TURP specimens for the 1997-1999 period represents a shift in PCA staging. Some PCAs previously staged as T1b are now staged as T2 carcinomas, as a result of PSA screening and earlier clinical detection. The introduction of PSA screening has had no influence on the incidence of T1a PCA, PIN, or AAH in TURP specimens.

Adenocarcinoma↗

PubMed2006

Detection rates of high-grade prostate cancer during subsequent screening visits. Results of the European Randomized Screening Study for Prostate Cancer.

Screening for prostate cancer using prostate-specific antigen (PSA) tests has led to a stage and grade shift as compared to the pre-PSA era. Effectiveness of screening for prostate cancer should be manifested by a reduction in detection rate of aggressive cancers during subsequent screening. In 6 centers of the European Randomized Screening study for Prostate Cancer, a total of 58,710 men were tested for prostate cancer. Screening centers differed with regard to age-range, screening interval and biopsy indications. During the 2nd visit, the proportion of Gleason score 6 cancers increased from 62.5 to 75%, mainly at the expense of Gleason score 7 cancers. High-grade (Gleason score 8-10) cancer detection rates varied per screening center during the 1st visit from 5.1 to 41.1, and during the 2nd visit from 6.4 to 29.3/10,000 men. The overall detection rate of high-grade cancers showed a reduction during the 2nd visit from 26 to 12/10,000 men, an effect mainly attributable to the screening center with the highest cancer detection rate (i.e. 507/10,000 men). Variations in detection rates among screening centers related among others to biopsy compliance and age range.

Age Factors↗

PubMed1997

Changes in patterns of prostate cancer care in the United States: results of American College of Surgeons Commission on Cancer studies, 1974-1993.

BACKGROUND: Advances in medical and public health practice have led to many changes in patterns of prostate cancer care. Data from several studies of prostate cancer by the Commission on Cancer of the American College of Surgeons provide information on the directions, magnitudes, and consequences of these changes. METHODS: The Commission on Cancer conducts patient care evaluation (PCE) studies based on the voluntary participation of hospital cancer programs and their tumor registries. PCE studies have been conducted repeatedly for prostate cancer covering patients diagnosed as early as 1974 and as recently as 1990. In addition, the National Cancer Data Base of the Commission on Cancer collects data for all forms of cancer from throughout the country. The Commission on Cancer, the American Cancer Society, and the American Urologic Association also has conducted a focused survey of radical prostatectomy outcomes. In aggregate, these multiple studies have accrued 179,366 reports on treatment of prostate cancer patients. RESULTS: Predominant among practice changes are new techniques of prostate cancer detection and initial evaluation which have led to shifts in disease stage at the time of initial therapy. The proportion of prostate cancer that is localized at the time of detection has increased. Use of radiation therapy and radical prostatectomy has increased as the selection of hormone treatment and no cancer-directed treatment have decreased. Five-year prostate cancer survival has improved for every stage of disease. CONCLUSIONS: The multiple studies by the Commission on Cancer provide data that are not available from other sources. Continued monitoring of prostate cancer patterns of care may be useful in measuring progress in control of this common disease.

Aged↗

PubMedDate not supplied

Endocrine treatment in prostate cancer.

Over its natural course, prostate cancer is a heterogeneous tumour with a generally slow but constant rate of growth. The androgen dependence of the prostate gland was demonstrated more than half a century ago by the landmark studies of Professor C. Huggins and colleagues. They established that androgens are implicated not only in growth regulation of the normal gland but also in the pathogenesis of prostate cancer, and that this malignant tissue retains some degree of androgen dependence. This concept was supported by studies of symptomatic clinical cancer, with androgen ablative therapy bringing relief to the patient in more than 80% of the cases. The classical treatment consisted of either bilateral orchiectomy, or administration of diethylstilbestrol (DES). Other forms of therapy followed, involving successive waves of new compounds that either withdrew androgen support from the cancer or blocked the androgens from their receptors in the prostate cancer cells. Chronologically, the progestagens can be well recognised, with one in particular: The successful derivative, cyproterone acetate (CPA). There also have been a number of oral vs. parenteral estrogens, the development of the luteinizing hormone-releasing hormone agonists (LH-RHA), the introduction of the non-steroidal anti-androgens characterised by flutamide and casodex, and more recently, the introduction of the LH-RHA. Moreover, there have been multiple possible forms of combination treatment to obtain maximal androgen blockade (MAB). However, no major differences in treatment outcome have been reported during the last 5 decades and most treatment choices have been based on tradition, associated side effects, the preferences of a particular doctor and patient, together with economic considerations. Furthermore, endocrine treatment has never been shown to cure clinical prostate cancer, which consequently has led to initiatives to defer endocrine treatment or to use it intermittently or use it as a form of neo-adjuvant or adjuvant treatment with surgery or radiotherapy. The history of endocrine therapy is replete with clinical trials that do not represent the patient population in general, and these trials share the clinical fact that they ignore the 20% to 30% of all patients who lack an initial response to a given endocrine treatment. Thus, it is no wonder that prognostic factors determine the outcome more than the treatment itself. Important to current endocrine treatment, however, is the shift to earlier stages of prostate cancer at initial diagnosis. Integration of endocrine treatment at this earlier phase in the pathogenesis of prostate cancer will substantially alter the treatment strategy in relation to long-term benefit with regard to survival, associated side effects, and costs. This complex adjustment is enhanced by recent discoveries in the molecular biology of the prostate which show, on the one hand, that the dihydrotestosterone-androgen receptor (DHT-AR) complex is important in the regulation of gene expression, but also that a number of intrinsic factors (e.g., peptide growth regulatory factors) can, through various paracrine, autocrine or intracrine interactions, exercise a major influence on cellular homeostasis and the regulation of prostatic growth.

Androgen Antagonists↗

PubMedDate not supplied

An economic appraisal of alternative strategies for the delivery of MCH-FP services in urban Dhaka, Bangladesh.

The strategy of distributing maternal and child health and family planning (MCH-FP) services at the doorsteps of the clients--through routine visits to the eligible couples by trained fieldworkers--has been instrumental in increasing the contraceptive prevalence rate (CPR), reducing fertility and attaining a considerably high immunization coverage of children and women in Bangladesh. The doorstep strategy, however, appeared to be labour-intensive and costly. With the maturity of the programme, priorities of the national MCH-FP programme have shifted to a stage that calls for more cost-effective service-delivery strategies, capable of offering a broader package of reproductive and other essential health services. The main objective of the present study was to examine the cost and effectiveness implications of the alternative strategies of delivering services from fixed sites--field-tested within an ICDDR,B operations research--in comparison to the conventional (existing) doorstep strategy. The key findings of the economic appraisal indicated that, at the end of the operations research intervention, both cost per birth averted and cost per QALY gained were lowest for the option of delivering services from static (fixed-site) clinics: US$13 and US$17 compared with the corresponding values of US$18 and US$42 for the doorstep strategy. Provision of health and family planning services from clinics--complemented with a reduced system of outreach workers to inform and target the hard-to-reach clients--was found to be the most cost-effective service-delivery alternative.

Adolescent↗

PubMed1979

Stage of palate closure as one indication of "liability" to cleft palate.

A new inbred mouse strain, SW/Fr, developed from a random-bred SW stock has a 6% incidence of spontaneous cleft palate without cleft lip. SW/Fr mice close their palates comparatively late in development. After cortisone treatment, the mean of the distribution (mean time to reach palate stage 5) is shifted towards later gestational ages. There is no change in the variance of the distribution. These data lend further support to the hypothesis that cleft palate in mice may fit a model where a continuous distribution is separated into discontinuous parts by a developmental threshold, and that time of palate closure is an important component of liability to cleft palate.

Animals↗

PubMed2005

Breast cancer in sub-Saharan Africa: how does it relate to breast cancer in African-American women?

BACKGROUND: African-American women have had a lower incidence, yet higher mortality rate from breast cancer compared with White-American women. African-American women also have had a higher risk for early-onset, high-grade, node-positive, and hormone receptor-negative disease. Similar features have characterized hereditary breast cancer, prompting speculation that risk factors could be genetically transmitted. Further evaluation of this theory required the study of breast cancer among women from sub-Saharan Africa because of their shared ancestry with African-American women. METHODS: Publications from 1988 to 2004 of English-language literature on breast cancer in Africa were reviewed. RESULTS: Women from sub-Saharan Africa were found to have a low incidence of breast cancer. This was partly explained by a largely protective reproductive history, including late menarche, early menopause, high parity with prolonged breastfeeding, irregular menses, and fewer ovulatory cycles. The average age at diagnosis, however, was approximately 10 years younger than breast cancer patients of western nations, and disease stage distribution was shifted toward more advanced disease, which resulted in higher mortality rates. These features were found to be similar to data on breast cancer in African-American women. Mutations in BRCA1 and BRCA2 have been reported in African-American women, but the extent of the contribution of BRCA1 and BRCA2 to breast cancer burden in Africa was uncertain. Limited financial resources lead to suboptimal cancer data collection, as well as delayed diagnosis and treatment of many African breast cancer patients. CONCLUSIONS: Parallels between breast cancer burdens of African-American and sub-Saharan-African women were provocative, indicating the need for further exploration of possible genetically transmitted features related to estrogen metabolism and/or breast cancer risk.

Africa South of the Sahara↗

PubMed1991

The effects of orchidectomy and gonadotropins on steroidogenesis and oogenesis in Bidder's organs of the toad Bufo woodhousii.

In the family Bufonidae, male toads possess rudimentary ovaries, called Bidder's organs, which are attached to the testes. The mechanisms involved in the inhibition of oogenesis in these structures were investigated in male Bufo woodhousii. Orchidectomized and sham-operated animals were injected with gonadotropins (pregnant mare serum gonadotropin [PMSG] + human chorionic gonadotropin [hCG]) for 26 days and the effects of these hormones on oogenesis and steroidogenic activity (3 beta-hydroxysteroid dehydrogenase [3 beta-HSD] and 17 beta-HSD) in the Bidder's organ were quantified. Bilateral orchidectomy alone resulted in the growth of bidderian oocytes and a shift towards later stages of oogenesis. Gonadotropins enhanced this effect and stimulated the proliferation of new germ cells. In the presence of testes, however, bidderian oogenesis remained inhibited despite high levels of circulating gonadotropins. In both ooplasm and follicular layers of the bidderian oocytes of all toads, 3 beta-HSD and 17 beta-HSD activities were detected by histochemistry. Follicular enzymatic activity increased in orchidectomized toads treated with PMSG + hCG but decreased in sham-operated toads treated with gonadotropins. Testis weights, rudimentary oviduct weights, and plasma steroid levels increased in intact toads injected with hCG + PMSG. Gonadotropins had no effect on plasma steroid levels in orchidectomized toads, however. These results suggest that the testes play a major role in the inhibition of oogenesis in Bidder's organs of B. woodhousii and are a major source of androgens. High circulating levels of gonadotropins do not overcome the inhibitory effects of the testes.

Analysis of Variance↗

PubMed2003

Fecal occult blood screening--trial evidence, practice and beyond.

Colorectal cancer is a leading cause of morbidity and mortality in Western countries. Primary prevention and early detection of this malignancy has been shown in multiple research set-ups, and using different modalities, to be effective in reducing the incidence and mortality rates of this disease. Three randomized controlled trials have been conducted over the last 30 years to evaluate the efficacy of periodic screening with fecal occult blood tests (FOBT). These studies have consistently demonstrated mortality reduction with biennial as well as annual testing after 8-18 years of follow-up. A significant primary prevention effect through reduction of colorectal cancer incidence was also reported. The results of the Israeli population-based screening program using Hemoccult Sensa show that it is possible to achieve a high detection rate in a well-organized community set-up and, in addition, also a shift in tumor stage towards smaller tumors, a low positivity rate, and an acceptable false positivity rate. FOBT is cheap and performs very well in cost effectiveness analyses evaluating the cost of detecting one cancer. This is quite a rare situation where mortality reduction can be achieved with a simple rather than a sophisticated technology. Research to further enhance the cancer detection capabilities of FOBT through the incorporation of molecular testing of the stool for tumor genes is underway. Multiple policymakers are already recommending this procedure for routine screening of average risk population. Taking their recommendations into action is of major importance.

Clinical Trials as Topic↗

PubMed1975

Lymphocyte differentiation and antibody synthesis in the secondary immune response of peroxidase stimulated lymph nodes of rat.

Lymphocyte differentiation and specific antibody synthesis were studied in the course of the secondary immune response of horseradish-peroxidase immunized rat popliteal lymph nodes by electron microscopic immunocytochemistry. From primary immunization, mature plasma cells containing specific antibody remained as long as 10 months. Antihorseradish peroxidase antibodies were localized in lymphocytic blast cells on Day 3 after restimulation with antigen. In the subsequent days blast cells were still present, and shifting to mature stages occured. During immunocyte differentiation and maturation vesicles and tubules of the Golgi complex became filled with specific antibody suggesting occasional secretion of antibody via the Golgi apparatus. At very mature cell stages, antibody was accumulated in distended cisternae.

Animals↗

PubMed2000

Resistance to freshwater exposure in White Sea Littorina spp. II: Acid-base regulation.

Parameters of acid-base and energy status were studied by in vivo 31P-nuclear magnetic resonance spectroscopy in three White Sea Littorina spp. (L. littorea, L. saxatilis and L. obtusata) during prolonged anaerobiosis in freshwater. Intracellular pH decreased significantly, especially during the early period of anaerobiosis, but later the decrease in intracellular pH slowed down considerably, suggesting a capacity for intracellular pH regulation in all three species. There was a trend for intracellular pH to fall most rapidly in the least freshwater-resistant species, L. obtusata, as compared to the most resistant, L. littorea. Non-bicarbonate, non-phosphate buffer values estimated by the homogenate technique were similar in the three studied species (28-37 mmol pH(-1) kg(-1) wet weight) and did not change during freshwater exposure. The CaCO3 buffer value of the foot tissues was considerably higher (171-218 mmol pH(-1) kg(-1) wet weight) and decreased significantly during freshwater exposure. The contribution of the multiple tissue buffering systems to intracellular pH regulation in Littorina spp. shifts between different stages of freshwater exposure. Initially, the non-bicarbonate, non-phosphate tissue buffering system seems to be of major importance for metabolic proton buffering at intracellular pH between 7.5 and 7.0. During later stages of anaerobiosis and at lower intracellular pH, the CaCO3 buffer is involved in proton buffering. Decrease in the CaCO3 buffer value during freshwater exposure was in quantitative agreement with the amount of metabolic protons buffered, thus suggesting that CaCO3 tissue stores may serve as a major buffering system during prolonged anaerobiosis in Littorina spp.

Acid-Base Equilibrium↗

PubMed1991

The effect of 'conditioning' exposures on hearing loss from traumatic exposure.

The role of 'conditioning' exposures as moderators of hearing loss produced by exposure to a higher level noise was explored using chinchillas. Monaural chinchillas were exposed to an octave band of noise centered at 0.5 kHz at 95 dB for six hours/day for ten days. The subjects were allowed to recover to pre-exposure sensitivity and at five days after the last exposure they were re-exposed to the same noise at 106 dB. Thresholds recorded at various time intervals following the second exposure were compared with those recorded in a control group exposed only to the higher level noise. The experimental animals were found to have less threshold shift at all stages of recovery. Results are discussed in the light of results of other related studies and possible mechanisms involved are hypothesized.

Acoustic Stimulation↗

PubMed1994

Patient population analysis in EORTC trial 22881/10882 on the role of a booster dose in breast-conserving therapy.

The changing composition of the patient population in breast cancer, which has been reported over the last decade, has important consequences for prognosis. In the present trial, an analysis of the population in an EORTC trial (22881/10882) on breast-conserving therapy was conducted. A shift towards earlier stages has been seen stage per stage, therefore better survival and local control rates are likely to be expected in comparison to previously published series. The majority of tumours in this trial were small, with a median clinical size of 2 cm and a median pathological size of 1.5 cm. A substantial number of lesions were detected in a pre-clinical stage (17.8%). Nodal involvement was present in only 19% of all patients and usually in only a low number of nodes (only 4% of all patients had four or more nodes invaded). The median number of nodes examined was 12, the difference between institutions was large. There was a significant correlation between the number of nodes examined, the percentage of patients with positive nodes (P = 0.03) and the percentage of patients with massive axillary invasion (P = 0.003). The correlation between clinical evidence and pathological invasion of the axillary nodes showed that 15% of the clinical examinations were false-negative and 51% were false-positive. Pathological nodal invasion could be clinically predicted in only 31% of patients, and consequently clinical examination of the axilla was a poor predictor of prognosis in this study. Pathological invasion of axillary lymph nodes was better correlated to pathological tumour size than clinical or radiological size.

Breast Neoplasms↗