We thank Lai[1] for their interest in our study.[2] We agree with their comments that pyogenic liver abscess (PLA) might be considered as a red flag sign of hepatocellular carcinoma (HCC). In our study, compared with the general population, patients with PLA had significantly higher risks of developing cancers, especially liver cancer, biliary tract cancer and colorectal cancer. The highest standardised incidence ratio occurred within 90 days after the diagnosis of PLA. Moreover, PLA and HCC with tumour necrosis are usually difficult to distinguish in the initial clinical presentations.[3] Consequently, it is reasonable to consider PLA as the herald of HCC.

Nevertheless, the risk of cancer remained elevated even 5 years after the diagnosis of PLA. In this aspect, the development of HCC in the long-term follow-up period may be less likely due to a delayed diagnosis of occult HCC. Previous studies demonstrate that the incidences of PLA are higher in patients with diabetes mellitus and cirrhosis, which are also the important risk factors for developing HCC.[4, 5] Consequently, the risks of HCC are persistently high in these patients even in the long-term follow-up period due to their underlying diseases.

In our opinion, early risk of HCC following the diagnosis of PLA may represent an initial manifestation of occult HCC; while the long-term risk may be attributed to the underlying diseases of patients with PLA. Therefore, patients with PLA should receive an intensive surveillance for cancers both in the early and in the long-term follow-up periods.


  1. Top of page
  2. Acknowledgement
  3. References

The authors’ declarations of personal and financial interests are unchanged from those in the original article.2


  1. Top of page
  2. Acknowledgement
  3. References
  • 1
    Lai SW. Letter: pyogenic liver abscess is a red flag sign of hepatocellular carcinoma. Aliment Pharmacol Ther 2012; 36: 906.
  • 2
    Kao WY, Hwang CY, Chang YT, et al. Cancer risk in patients with pyogenic liver abscess: a nationwide cohort study. Aliment Pharmacol Ther 2012; 36: 46776.
  • 3
    Lin YT, Liu CJ, Chen TJ, et al. Pyogenic liver abscess as the initial manifestation of underlying hepatocellular carcinoma. Am J Med 2011; 124: 115864.
  • 4
    Foo NP, Chen KT, Lin HJ, Guo HR. Characteristics of pyogenic liver abscess patients with and without diabetes mellitus. Am J Gastroenterol 2010; 105: 32835.
  • 5
    Molle I, Thulstrup AM, Vilstrup H, Sorensen HT. Increased risk and case fatality rate of pyogenic liver abscess in patients with liver cirrhosis: a nationwide study in Denmark. Gut 2001; 48: 2603.