Who Should Get a Right Colectomy in Low-Grade Appendiceal Adenocarcinomas?

Waheed MT, Malik I, Blakely AM, et al. Who Should Get a Right Colectomy in Low-Grade Appendiceal Adenocarcinomas? Association of Lymphovascular Invasion and Nodal Metastases. Surgery (2024).

Appendiceal adenocarcinomas (AA) are rare cancers accounting for 0.4% of gastrointestinal neoplasms. Clinical practice guidelines recommend that these tumors be treated with right hemicolectomy (RHC) to ensure complete removal of nodal metastases; available data cited in this article showed that 2/3 of patients who undergo RHC did not have nodal involvement.

This article reported a study that described development of a predictive score for determining risk for nodal involvement. Components of the scoring system included lymphovascular invasion, non-mucinous histology and T3/T4 tumor stage.

Lymphovascular invasion was documented in 6.9% of the 1,303 included patients. A composite score of 0 was associated with a 3.9% risk of nodal metastasis and hemicolectomy did not improve survival in this patient group.

The authors concluded that the composite score could be used to determine the need for RHC in patients with low grade AA. Of note are the facts that the authors emphasized the practice guidelines recommendation for histologic examination by an “expert pathologist” but did not state whether the composite score could be calculated based on frozen section histology at the time of primary appendectomy.