Prognostic effect of pregnancy on young female patients with nasopharyngeal carcinoma: results from a matched cohort analysis

Objectives We aimed to evaluate the prognosis of pregnancy-associated patients with nasopharyngeal carcinoma (NPC) in a young population. Methods From June 1999 to December 2010, 51 patients aged ≤ 35 years who were diagnosed with NPC during pregnancy or within one year after delivery were admitted into the pregnancy-associated group in our institution. An additional 51 patients who were not pregnant at diagnosis were selected from 451 patients based on the matching criteria to match the pregnancy-associated female patients. The primary endpoint was overall survival (OS). The secondary endpoints were progression-free survival (PFS) and distant-metastasis failure-free survival (DMFS) and locoregional failure-free survival (LRFS). Results The advanced stage was not different between the pregnant and the non-pregnant group before matching (69.8% vs. 70.3%, P = 0.690). No difference in OS at the median follow-up time of 92 months was observed between the pregnancy-associated and the non-pregnant group (85.4% vs. 92.2%, P = 0.478); likewise, no differences were observed regarding PFS and DMFS. However, the pregnancy-associated group had worse LRFS than the non-pregnant group (84.8% vs. 95.9%, P = 0.033). When the pregnancy-associated patients were dichotomized into an early pregnancy group and a late pregnancy group, our data showed that pregnancy interval did not seem to impact the risk of death or relapse. Conclusion Our results show that patients in the pregnant group did not seem to have more advanced stage or inferior survival than that in the non-pregnant group.