Occult neoplastic cells and malignant micro-aggregates in lymph node sinuses: review and hypothesis.
Many studies have shown a close relationship between the detection of occult neoplastic cells (ONCs) freely floating in lymph node sinuses remote from the primary tumor and the recurrence/metastasis of various malignancies. If 5 to 10 circulating ONCs form an aggregate of tumor cells, it may easily escape attack by the host immune system. Since such malignant micro-aggregates cannot pass through the circulation in the liver and lungs, which filter tumor cells from the blood, the aggregates may become anchored in these organs and cause metastasis. A hypothesis is proposed that the most important factor leading to distant metastasis/recurrence of stage I or II cancer without microscopic lymph node metastasis, so-called N0 local disease (N0-LD), is the release of malignant micro-aggregates consisting of many ONCs from the primary tumor. Distant metastasis/recurrence of N0-LD may occur when such infiltrating/proliferating cells enter target organs, especially the liver and lungs, in a viable state during their first pass through the circulation preoperatively and/or intraoperatively.
Mukai
Masaya
M
Tokai University Oiso Hospital, Department of Surgery, Gakyou 21-1, Oiso, Kanagawa 259-0198, Japan. onc-res@oiso.u-tokai.ac.jp
D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008954:Models, Biological; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis; D009367:Neoplasm Staging; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology*