We read with great interest the recently published article by van Driel et al. [1] in The New England Journal of Medicine, which reported that the single administration of hyperthermic intraperitoneal chemotherapy (HIPEC) to interval cytoreductive surgery (CRS) increases survival in patients with advanced ovarian cancer. This finding is encouraging; however, some aspects of the study warrant closer attention.

First, lymph node involvement is common in advanced ovarian cancer that is an established prognostic factor. The extent of lymphadenectomy and the number of positive nodes are associated with survival of patients with advanced ovarian cancer [2]. The current recommendations regarding lymphadenectomy in advanced ovarian cancer remain debatable. Did all the trial patients receive systematic lymphadenectomy or lymph node sampling as a part of CRS? This trial did not report surgery information about lymphadenectomy, which was a potential confounding factor. Second, intraabdominal temperature of 40.0°C was maintained in this trial, but in another randomized phase III study by Spiliotis et al. [3], the temperature setting of HIPEC was 42.5°C. Therefore, it would be interesting to know whether the increase of temperature in HIPEC within an appropriate range will improve the outcome. In addition, a study [4] has suggested that HIPEC with cisplatin and paclitaxel after CRS is feasible with acceptable morbidity, the role of which merits further investigations.

In short, despite the scientific merit of this trial, further clinical studies are necessary before HIPEC can become a practice-changing option for advanced ovarian cancer.