Recent studies1-5 have been reported from several laboratories demonstrating the presence of malignant cells in the blood streams of patients having malignant neoplasm. The cytologic studies are positive for malignant cells in a significant number of patients in blood specimens drawn from the peripheral blood as well as from the regional veins draining the tumor. Of even greater importance is the observation that showers of cancer cells may follow various types of tumor manipulation, such as diagnostic examinations (pelvic exams), surgical preparation of skin (mammary tumors), and operative procedures.
These excellent studies serve to confirm the works of Tyzzer,6 who in 1913 demonstrated that gentle massage of a transplanted carcinoma in a mouse greatly increased the number of metastases in the lung, and of Knox7 (1922), who observed that gentle massage of tumors in the mouse increased the number of tumor emboli which can produce metastatic tumors.
BERENS JJ. Management of Breast CancerWith Special Reference to Prevention of Metastases by Seeding of Malignant Cell from Self-Examination and Operative Manipulation. Arch Surg. 1961;82(5):662-664. doi:10.1001/archsurg.1961.01300110024003