Recurrence and 5-FU sensitivity of stage I/II node-negative breast, lung, or gastric cancer with occult neoplastic cells in lymph node sinuses.

This study was designed to examine the relationship between the presence of occult neoplastic cells (ONCs) in lymph nodes (LNs) and survival in 238 patients with stage I/II LN-negative cancer of the breast, lung, or stomach. In addition, immunohistochemistry for TS and DPD was used to compare the 5-FU sensitivity of the primary tumor in ONC (+) patients. The 5-year relapse-free survival (RFS) rate of 215 ONC (-) patients and 23 ONC (+) patients was 95.2 and 82.6%, respectively (p=0.0107). The 5-year overall survival (OS) rate of the ONC (-) and (+) patients was 97.4 and 77.4%, respectively (p=0.0000). The 6 ONC (+) patients with recurrence showed high and low TS expression in 33.3% (2/6) and 66.7% (4/6), respectively, while high and low DPD expression was observed in 16.7% (1/6) and 83.3% (5/6), respectively. In the 17 ONC (+) patients without recurrence, the corresponding values were 64.7% (11/17), 35.3% (6/17), 29.4% (5/17), and 70.6% (12/17). Patients with a combination of high TS and low DPD expression accounted for 33.3% (2/6) of the ONC (+) patients with recurrence and 52.9% (9/17) of those without recurrence, showing no significant difference between the two groups. These results suggest that ONCs are associated with a lower survival rate and that ONC (+) patients are unlikely to respond to 5-FU+LV therapy.