Reports of two cases, in JAMA and in the Archives of Pathology and Laboratory Medicine, respectively, present unusual phenomena that merit readers' attention.1 In the first case, Ashby and Dappen (p 2519) were interested principally in the extraordinary rarity of any patellar neoplastic disease, whether benign or malignant, or primary or secondary. Only 15 cases of metastasis to the patella had been described in the literature before the authors added the 16th. In the second report, Krumerman and Katatikarn dwelled on the infrequency of bladder rhabdomyosarcoma in adults and on the manner of the tumor's intraepidermal migration. Incidentally, the neoplasm had also spread to the pelvic bones and lumbar vertebrae.
Understandably, neither case report included discussion of the route by which the respective neoplasms arrived at the involved bones; such discussion was not germane to the authors' prime purposes. Yet, the facts of metastasis deserve editorial comment if for