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Biomedical subjects

R W Giard

Publications and source records attributed to R W Giard.

At least 19 recordsLinked to original sources
PubMed2004

[Sensitivity and speed of cell and tissue pre-diagnosis among breast cancer patients undergoing primary surgical treatment in two hospitals, determined with the aid of PALGA data].

OBJECTIVE: Result and process testing of cell and tissue diagnostics, including the sentinel-gland procedure, executed on patients who underwent a primary surgical intervention for mammary carcinoma. DESIGN: Retrospective. METHOD: In a group of 191 women who underwent 192 primary surgical interventions for breast cancer in 2002, data from the Pathological-Anatomical National Computerised Archive (PALGA) were examined with regard to which form of cell or tissue diagnosis was used and in how many stages the cancer diagnosis was morphologically established with sufficient certainty. RESULTS: In three-quarters of the women the diagnosis 'cancer' was established with certainty in the first stage. When the initial diagnosis was made using fine-needle cytological puncture, 35 of the 81 women had to undergo a second diagnostic test; with histological tests using needle biopsies this was 10 out of 92. The false-negative chance of fine-needle cytological tests was 13% (95% CI: 8-22) and for tests involving large-core needle biopsies 14% (95% CI: 8-23). A delay in treatment of more than 4 months occurred in 6 women due to the cancer being missed. A sentinel-gland procedure was performed on 58% of the women. In 33 women who underwent pre-operative ultrasound with fine-needle cytological testing of the axillary glands, the sensitivity for axillary gland metastases was 74% (95% CI: 53-87). CONCLUSION: Looked at in terms of the practical guideline for diagnosis of breast cancer the cell and tissue diagnoses were adequate, but the standards prescribed in that guideline for the chances of a false-negative (5%) were exceeded.

Adult↗
PubMed2004

[Evaluation of frozen sections and cytological diagnosis during surgery].

When a surgeon feels it to be necessary to carry out morphological diagnosis during the operation, the pathologist may assist him or her with rapid cell or tissue diagnosis. This must be a conscious decision to introduce an additional step into the chain of laboratory procedures from the taking of the sample to the reporting of the result. Because this additional phase requires a longer stay in the operating room and additional effort on the part of the laboratory staff, together with an increased risk of misclassification of the disease process, this step should only be taken after careful consideration of the pros en cons. On the one hand, the need for intra-operative diagnosis has decreased because of the availability of better and more accurate pre-operative diagnostic techniques; on the other hand, there are new developments such as the introduction of sentinel-node biopsy, in which one must weigh the advantages of a rapid intra-operative diagnosis against the slower but surer results of a more comprehensive lymph-node investigation. Routine examination of the cut edges during an operation is hardly ever done any longer as a result of changed biological knowledge regarding the margins needed for radical surgery.

Biopsy↗
PubMed2004

[The yield of breast cancer screening: the importance of observational data and the problems of bias].

Descriptive studies are important for the analysis of the effects of medical interventions. Especially in breast cancer screening, where the balance between gains and losses is often difficult to establish, detailed, empirical, long-term follow-up data on outcomes are of vital importance. Recent Dutch data comparing the prognosis, tumour stage at diagnosis and surgical treatment before and after the introduction of a population-based breast cancer screening programme reveal a better prognosis and a more favourable tumour stage after introduction of the programme. However, these data have their limitations. The interpretation of such figures is hampered by different types of bias (lead-time, length and over-diagnosis). The final assessment is always subjective and prone to confirmation bias.

Breast Neoplasms↗
PubMed2003

[Screening: careful considerations versus commercial medicine].

People no longer seem to view their state of health in a light-hearted manner. The worried well hunger for every scrap of information they can find about their physical well-being, with the result that a veritable diagnostic industry is developing. Is the early detection of a disease always better than waiting for its signs or symptoms? It is difficult to answer this question and properly weigh up the beneficial effects against the side effects. Two main reasons are given for this. First of all, studies on the early detection of disease report the results selectively: beneficial effects are overstated and side effects are underreported. A more comprehensive evaluation method is needed. Secondly, new technological and therapeutic innovations are in competition with the existing techniques under investigation, which makes a long-term evaluation almost impossible. Moreover, this approach obscures questions fundamental to screening practices. There is a widening gulf between medical screening and traditional medicine, with the result that care is being transformed into a commercial product with a huge market. These developments in diagnostics pose new scientific and ethical questions that need to be answered.

Cost-Benefit Analysis↗
PubMed2001

[Breast cancer screening lacking effectiveness].

The recent Cochrane review on mammographic breast cancer screening disclosed no convincing reduction of breast cancer mortality, together with an increase in the number of aggressive treatments. Given this outcome, there no longer exists solid experimental evidence to support mass screening. In the Netherlands over 800,000 women are invited to participate in this activity yearly. Is this still justifiable? The final answer rests on the conclusions from the analyses carried out from three different perspectives. From the methodological viewpoint, a broad re-analysis is needed which also takes the long-term adverse effects of radiotherapy into account. From the tumourbiological perspective, whether 'early' diagnosis really has potential therapeutic consequences should be explored further. From a societal perspective, more detailed and balanced information is required, since expectations regarding the effect of screening are unrealistic. Given the preliminary outcomes of these analyses, there are now serious reservations as to whether continuation of screening is justified. Women should be informed about this matter promptly.

Adult↗
PubMed2001

[Medical errors: inevitable but preventable].

Medical errors are increasingly reported in the lay press. Studies have shown dramatic error rates of 10 percent or even higher. From a methodological point of view, studying the frequency and causes of medical errors is far from simple. Clinical decisions on diagnostic or therapeutic interventions are always taken within a clinical context. Reviewing outcomes of interventions without taking into account both the intentions and the arguments for a particular action will limit the conclusions from a study on the rate and preventability of errors. The interpretation of the preventability of medical errors is fraught with difficulties and probably highly subjective. Blaming the doctor personally does not do justice to the actual situation and especially the organisational framework. Attention for and improvement of the organisational aspects of error are far more important then litigating the person. To err is and will remain human and if we want to reduce the incidence of faults we must be able to learn from our mistakes. That requires an open attitude towards medical mistakes, a continuous effort in their detection, a sound analysis and, where feasible, the institution of preventive measures.

Humans↗
PubMed2001

[Increasing importance of cytological diagnostics in the Netherlands].

Cytological diagnosis has important practical clinical value, as shown by the observation that 54% of all diagnostic activities in pathology laboratories consist of cytological investigations. New impulses are, however, required to ensure ongoing developments. For example, from a scientific point of view, there appears to be little evidence-based information. A shift from case reports to systematic evaluation and from descriptive to prescriptive research is needed. The discipline of cytological diagnostics requires greater academic interest, and better guidance and structuring.

Cytodiagnosis↗
PubMed2001

[Doctors are increasingly held liable for missed diagnosis of cancer in mass screening].

Radiologists and pathologists are increasingly subjected to litigation for alleged faults in diagnosing cancer. An important cause of this appears to be the introduction of mass screening for cancer. According to liability law, the judge must assess whether the person making the diagnosis effected his/her duty with due care. The distinction between error and incompetence cannot be judged solely on the basis of the individual case, but requires an estimation of the accuracy of the diagnosis on a population level. The traditional role of the expert witness, who is asked to judge the individual cases, needs to be reconsidered. A re-examination of slides or radiograms with prior knowledge of the outcome obtained does no justice to the original situation and an alternative procedure is therefore needed. Since the government initiates and controls population screening and the professional organisations involved in screening have committed themselves to monitoring the process and the results obtained, the general public must be better informed about the limitations of screening. Unrealistic expectations as to the benefits of screening appear to be an important motive for legal actions. It is questionable whether screening quality can be enhanced by means of the preventive effect of professional liability. Doctors and lawyers should analyse and solve this problem together.

Diagnostic Errors↗
PubMed2001

[Evaluation of the Dutch Medical Treatment Act, five years after implementation: subjective and poorly substantiated].

Five years after its implementation, the Dutch Medical Treatment Act, which regulates the doctor-patient contract, was evaluated. Two subjects were investigated: the right of the patient to be informed and to give informed consent and the way physicians deal with personal information. From a methodological point of view, this appraisal was very disappointing. At best, the evaluation report is descriptive but not evaluative: no comparative study was carried out before and after the law was implemented to ascertain effects. The Act is difficult to evaluate in practice as its goal, improving the legal position of the patient, is dogmatic. Its regulations on informed consent and agreement as well as the rules of law concerning the use of patient data for clinical research, have at times proved to be impractical even though such legal directives appear to be reasonable. The problems addressed by this law should be more widely debated and be subjected to a far more rigorous validation process.

Confidentiality↗
PubMed2001

[Care for body materials obtained from autopsy].

During every autopsy, small tissue samples are taken from each organ for microscopic examination. Organs or part of organs are retained for a longer period if (a) the organ concerned is so small that the entire organ is needed for the microscopic examination; (b) the organ exhibits complicated abnormalities which can only be diagnosed following fixation or a special treatment; (c) the organ must be fixed before the examination can take place, for example, the brain. This means that the corpse is not buried or cremated in its entirety. Next of kin are not always aware of this procedure even if they have given their consent for an autopsy. Changes within society, especially the handling of aborted foetal material and foetal material from intra-uterine deaths, require new agreements and rules for the retention of organs. Next of kin must be able to have confidence in the provision of information and the careful management of body material retained during autopsies.

Autopsy↗
PubMed2001

[Mix-up of patient specimens: error prevention through a systems approach].

A correct diagnosis may reach the wrong patient because of a mix-up of either diagnostic specimens or identification data. It is astonishing how little attention is paid to this problem in medicine while the scale, the reach and the complexity of diagnosis are growing fast. More research is urgently needed to detect and investigate these types of errors. There is no quick remedy for this problem: a systems approach with comprehensive assessment of potential risks and subsequent management is the only sensible way out. Regrettably it is impossible to completely eliminate swapping errors, at best they can be reduced to an absolute minimum.

Diagnostic Errors↗
PubMed2001

Extramedullary plasmacytoma of the breast simulating breast cancer.

A patient with a palpable mass in the breast suggestive of carcinoma underwent radical modified mastectomy. Surprisingly, histology of the tumor revealed an extramedullary plasmacytoma. Further diagnostic work up showed no evidence of underlying multiple myeloma. Among neoplastic lesions of the breast, although rare, malignancy of mesenchymal or lymphoproliferative origin should always be considered.

Aged↗
PubMed2000

Use and accuracy of fine-needle aspiration cytology in histologically proven thyroid carcinoma: an audit using a national nathology database.

BACKGROUND: Fine-needle aspiration cytology is recommended as the first and most decisive diagnostic step in the workup of patients with nodular thyroid disease. METHODS: A retrospective analysis of all thyroid carcinomas diagnosed was conducted using the Netherlands Pathology Database PALGA, which covers all cytologic and histologic examinations in the Netherlands, with the aim of investigating nationwide whether fine-needle aspiration cytology of the thyroid (FNAC-t) actually had been used prior to surgery for thyroid carcinoma and if so, with what result. RESULTS: FNAC-t was used in 591 of the 890 patients (66%) analyzed, with a total of 769 aspirations (a single FNAC-t in 459 patients, multiple FNAC-ts in 132 patients). The overall sensitivity rate was 57%; when restricting the FNAC-ts to the most recent one for each patient, the sensitivity rate rose to 70%. Sensitivity was lowest for follicular carcinoma (67%) and was highest for anaplastic and medullary carcinomas (89%). Limiting these calculations to aspirations from patients with tumors > 10 mm was found to have very little influence on these rates (FNAC rate: 71%; overall sensitivity rate: 58%). CONCLUSIONS: If the application rate (66%) and sensitivity for the most recent aspiration (70%) were considered regardless of the tumor size, only 47% of the malignancies were detected by FNAC-t. When patients with tumors > 10 mm and all FNAC-ts in this group are considered, only 41% of thyroid carcinoma cases were detected cytologically. Contrary to common belief based on current guidelines for the workup of patients with nodular thyroid disease, the majority of thyroid carcinoma cases are not detected by FNAC-t.

Adolescent↗
PubMed2000

[Population screening for cervical cancer; eventual gain not expected to increase by testing for papillomavirus].

Since the development of cervical cancer and its precursors is epidemiologically associated with oncogenic, high risk types of human papilloma virus (hrHPV), the availability of testing for hrHPV opens new dimensions for the much-criticised traditional cytological screening. It seems that hrHPV is a necessary but not in itself sufficient condition for the oncogenesis of cervical cancer. In women the prevalence of hrHPV is highest during their most active sexual phase in life, but most (> 95%) of the infections die out spontaneously and they rarely lead to cervical cancer. Only when viral infection persists together with other hitherto mostly unknown factors may cancer develop. Given the current status of research it is not advised to add testing for hrHPV to the current national screening programme or even replace cytological testing with hrHPV analysis: it makes screening definitely more complex but not better, while 'old' problems like overdiagnosis of abnormalities and subsequent overtreatment are far from being resolved.

Adult↗
PubMed2000

[Objective re-evaluation procedures in cases of possible diagnostic error].

Auxiliary diagnostic specialists such as clinical pathologists or radiodiagnosticians may be held liable by injured patients for erroneous diagnoses. Nearly always there will be a reconstruction of the situation in which the alleged misstake was made, and relevant facts will be tested against both professional and legal rules. The Court or one of the parties involved frequently ask an expert for re-evaluation of microscopic preparations, X-rays, etc. This objectivating evaluation requires a procedure that does justice to the original diagnostic situation and therefore should not be made by one single expert familiar with the chain of events. The results of the re-evaluation should be interpreted meticulously and their relative importance established by the Court.

Adult↗