Solitary necrotic nodule of the liver: always benign?

Solitary necrotic nodule of the liver (SNNL) is a rare lesion and accepted as a benign entity. The aim of this study is to investigate the possible causes for the development of solitary necrotic nodules.

Twenty-two retrospective solitary necrotic nodule specimens were examined to evaluate histologic features. The clinical records of these patients were reviewed, and clinical data were obtained for all patients.

Histologically, 17 of the 22 nodules were necrotic with surrounding fibrosis, and the remaining five nodules were completely fibrotic. Four of the 22 cases were found to have specific lesions within the nodules which may put light on the pathogenesis. Foci of metastatic carcinoma were identified in two of these four cases, and cuticle fragments of the hydatid cyst were identified in the other two cases. Clinical data showed that half of the cases with solitary necrotic nodule have an associated malignancy mainly involving the gastrointestinal system.

SNNL is not always benign. The possible causes of this lesion include parasites and metastatic tumors. It is important to identify the minute foci of metastatic carcinoma for the appropriate management of this lesion.