Evaluation of the significance of isolated tumor cells in gynecological cancers.

In gynecological oncology, sentinel lymph node biopsy with ultrastaging is increasingly used in cervical, endometrial and vulvar cancers. Isolated tumor cells (ITCs) are encountered much more commonly in this scenario than when standard histologic evaluation of non-sentinel lymph nodes is performed. The prognostic implication of ITCs in gynecological cancers is not well defined and international guidelines do not offer clear guidance regarding the management of gynecological cancers with ITCs. The current size cut-off for defining ITCs, micrometastases and macrometastases in lymph nodes are arbitrary and based on weak data. The detection rate of ITCs is strongly influenced by the "intensity" of pathological ultrastaging which varies greatly and there are resource constraints related to pathology services. However, even with standardized and intensive protocols, ITCs are by definition too small to be detected in all cases, and therefore it is challenging to completely define their prognostic risk. Moreover, in the absence of definitive evidence excluding their contribution to recurrence risk, we suggest that ITCs should be regarded as a potential negative prognostic risk factor and managed accordingly in clinical practice.