Margin status is a predictor of outcome for patients with liver malignancies, although what constitutes a negative margin is controversial. Traditionally, the completeness of resection is estimated by surgical histopathology of the resected specimen margin, despite the in situ margin being potentially more important. The true margin is often altered by parenchymal transection techniques. The authors propose that cytologic assessment of the in situ margin is more specific for determining the true margin.
A total of 84 patients with primary or metastatic liver tumors who were undergoing surgical resection were enrolled in this prospective Institutional Review Board-approved study. Specimen and in situ (patient) margins were assessed using a "scrape preparation" cytologic technique and compared with traditional surgical histopathology. Patients were followed for assessment of local disease recurrence.
Follow-up data were complete for 64 patients for a median of 37 months (range, 12 months-56 months). Twenty patients were excluded because of perioperative death (6 patients; 7%) or a follow-up of < 12 months. Seven patients (12.2%) had positive histopathologic specimen margins, but only 1 was found to be positive by cytology (1.8%). No in situ cytologically positive margins were identified along the cut edge of the liver remnant. The rate of intra- or extrahepatic recurrences was 56.7%, whereas the local recurrence rate was 1.8%. One patient with local recurrence demonstrated simultaneous intra- and extrahepatic disease recurrences and had negative margins by all methods of evaluation.
To the authors' knowledge, the current study is the first to demonstrate that in situ margins can be assessed using cytopathology. This method is quick and can be universally applied. Given the difficulty of accurately assessing margins after hepatectomy, cytopathologic evaluation may be more reflective of the true margin. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.