Among women 40 years of age or older, tumors with favorable biologic features made up 38.2% of the tumors that were 1 cm or less in the greatest dimension, and this steadily decreased to only 9.0% of the tumors greater than 5 cm, whereas tumors with unfavorable biologic features made up only 14.1% of the tumors 1 cm or less and increased to 35.8% of the tumors greater than 5 cm. Both tumor size and biologic features had a major influence on prognosis, but large tumors with favorable biologic features had a better prognosis than small tumors with unfavorable biologic features. Because of the long lead times, mammography is very good at detecting tumors with favorable biologic features, and therefore these tumors are overrepresented among small tumors. A study involving patients enrolled in the MINDACT (Microarray in Node-Negative and 1 to 3 Positive Lymph Node Disease May Avoid Chemotherapy) trial showed that mammography resulted in tumors diagnosed with favorable biologic features as assessed by MammaPrint.9 Third, our analysis assumes that the favorable low-grade, hormone receptor– positive tumors do not dedifferentiate over time to high-grade or receptor-negative tumors. Prospective studies do show a discordance in receptor status of 10 to 15% between the primary tumor and subsequent distant metastases, these changes are usually the result of selection pressures on the tumor because of treatment.10 It is thought that in the primary tumor, low-grade and high-grade tumors arise by different molecular mechanisms,11 and it is very rare for a low-grade tumor to dedifferentiate into a high-grade tumor.12 Fourth, it is likely that tumor biologic features represent a continuous variable, and our analysis, similar to those with Oncotype DX recurrence scores, involves dividing the patients into prognostic groups with the use of somewhat arbitrary cut points.
The current write-up by Welch et al. 1 in the Journal proved that given that the fostering of extensive testing mammography, tiny bust cancers cells have actually raised in occurrence over 3 times greater than big cancers cells have actually reduced. This indicates that lots of tiny cancers cells are not predestined to advance to big cancers cells; rather, their discovery leads to overdiagnosis. The function of our research study was to define teams of growths that are most likely to include a big part of overdiagnosed cancers cells and also to describe the device that might have resulted in their overdiagnosis.
Intrusive bust cancers cells that were identified in 2001– 2013 were determined from the Security, Public health, as well as End Outcomes (SEER) data source.2 They were split right into 3 prognostic teams based on biologic variables: quality, estrogen-receptor (Emergency Room) condition, and also progesterone-receptor (Public Relations) standing. The circulation of these 3 teams throughout growth dimension was established. We additionally checked out the organizations of growth dimension and also biologic attributes with bust cancer cells– details survival.
We embraced the technique by Etzioni et al. 3 to review the mean lead time (the size of time in between when a cancer cells could be discovered by testing as well as when it would certainly have come to be medically evident without testing) throughout the 3 prognostic teams. We initially used the price quote of Welch et al. 1 that the general price of overdiagnosis for intrusive lumps was 22%. We presumed that the lead time complied with a rapid circulation, and also we made use of Weibull circulations with even more and also much less severe lead times as level of sensitivity evaluations