MRI scan, Ultrasound, Petscan en scintimammography zijn onvoldoende accuraat in vaststellen van borstkanker in vergelijking met een biopt

10 mei 2023: lees ook dit artikel: https://kanker-actueel.nl/hoe-langer-het-duurt-voordat-borstdichtheid-afneemt-bij-ouder-wordende-vrouwen-hoe-groter-het-risico-op-ontstaan-van-borstkanker.html

23 februari 2006. Bron: Medscape

Een grote overzichtsstudie van 81 studies toont aan dat de veelvuldig gebruikte diagnose techieken als MRI scan, Petscan, Ultrasound en Scinti mammography (bij een verdachte mammografie of verdachte klachten gevonden door lichamelijk onderzoek) alleen onvoldoende aantonen dat er wel of geen sprake is van borstkanker. Een biopt blijkt uit deze overzichtstudie nog het meest accuraat in de vaststelling van borstkanker. We tekenen er wel bij aan dat bv. de AMAS test niet in dit onderzoek is meegenomen en bij een biopt lijkt het risico op tumorspill, het verspreiden van kankercellen door het prikken waardoor uitzaaiïngen zouden kunnen ontstaan niet als risico hier wordt genoemd.

De resultaten:
De negatief lijkende testgegevens tonen aan dat van elke 1000 vrouwen met een negatieve Petscan er 924 een onnodige biopt hadden gekregen, maar wel hadden 76 vrouwen een vaststelling van kanker gemist. Op elke 1000 vrouwen met een negatieve scintimammography 907 vrouwen hadden een olndnogie biopt gehad, maar 93 vrouwen hadden een vaststelling van kanker gemist. Van elke 1000 vrouwen met een negatieve MRI-scan, hadden ca. 962 vrouwen onnodig een biopt gekregen, maar 38 vrouwen hadden vaststelling van kanker gemist. Van elke 1000 vrouwen met een negatieve Ultrasound uitslag hadden 950 vrouwen onnodig een biopt gekregen, maar 50 vrouwen hadden de diagnose kanker gemist. Leest u verder onderstaand artikel met onderaan een link naar het volledige studierapport.

Feb. 10, 2006 — None of the 4 commonly used noninvasive tests for breast abnormalities are sufficiently accurate to preclude breast biopsy in average risk women, according to the results of The Agency for Healthcare Research and Quality (AHRQ) Effective Health Care Program comparative effectiveness review of magnetic resonance imaging (MRI), ultrasonography, positron emission tomography (PET) scanning, and scintimammography.

"So many women today undergo biopsies only to learn they do not have breast cancer," AHRQ Director Carolyn M. Clancy, MD, said in a news release. "But early and accurate diagnosis of breast cancer is crucial, and at this time, biopsies remain the most effective technique when mammography or physical examination reveals a potential problem. Hopefully, noninvasive tests can continue to improve so that in the future, there will be a viable alternative to biopsy."

A panel from the Evidence-based Practice Center in Plymouth Meeting in Pennsylvania identified 81 studies meeting inclusion criteria to evaluate the accuracy of MRI, PET, scintimammography, or ultrasound for diagnosing breast cancer in women. Based on the accuracy, sensitivity, specificity, and negative likelihood ratios of these tests, all could reduce the need for biopsy in women with an abnormal mammogram who do not have cancer, but each would miss some cancers.

In the United States, risk for breast cancer in a woman with an abnormal mammogram requiring a biopsy for evaluation is about 20%. For these women with average risk for cancer after an abnormal mammogram and nonpalpable lesions, the tests' negative likelihood ratios suggest that for every 1,000 women who had a negative PET scan, about 924 women would have avoided an unnecessary biopsy, but 76 women would have missed cancers. For every 1,000 women with a negative scintimammogram, about 907 women would have avoided unnecessary biopsy, but 93 women would have undetected cancers. For every 1,000 women with a negative MRI, approximately 962 women would have avoided an unnecessary biopsy, but 38 women would have missed cancers. For every 1,000 women with negative ultrasound, approximately 950 women would have avoided an unnecessary biopsy, but 50 women would have undiagnosed cancer.

Because each woman with an abnormality on mammogram or clinical examination may have a specific risk for breast cancer varying widely from the average, the patient and her healthcare provider should discuss the extent of cancer risk. The higher a woman's risk of breast cancer is before undergoing a noninvasive test, the higher the risk for cancer even if the test results are negative. None of these tests was sufficiently accurate to replace biopsy for women with nonpalpable lesions at average risk for breast cancer, assuming that a less than 2% risk of having breast cancer with a negative diagnostic test was considered an acceptable level of risk for a diagnostic test to reliably preclude biopsy. For only palpable lesions, data were insufficient to estimate the accuracy of PET scanning, MRI, ultrasound, and scintimammography. Although the authors are "moderately confident" that publication of future studies will not contradict these findings, they acknowledge limitations in their evidence base, including incomplete reporting of study design and patient characteristics, insufficient numbers of studies reporting data for particular subgroups of patients, and the extremely high prevalence of breast cancer in the patients enrolled. The authors also had insufficient evidence to estimate the accuracy of these tests in women whose mammogram indicates a lesion that probably is benign. "There is a wealth of information in this report that can give women and their health care providers detailed and helpful insight into the strengths and weaknesses of each of these techniques," Dr. Clancy concludes. http://www.effectivehealthcare.ahrq.gov/reports/final.cfm

borstkanker, Petscan, MRI scan, biopt