Answers are grounded in this paper and cite their sources.
From the SEER files of the NCI, 8,587 cases of breast cancer diagnosed in 1975 were analyzed. Of these cases, 5.3% were noninvasive. Of the invasive cancers under 0.5 cm in diameter, 17.2% had positive axillary lymph nodes. Where the physician recorded no palpable axillary lymph nodes, 34.5% were found to be positive.
No takes yet. Share an insight, caveat, or question.
Smart et al. (1978) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: