Operable colon cancer: New therapeutic perspectives,same old problems

Dear Editor,

We greatly appreciate Wetterholm et al.’s ¹ “CT is unreliable in locoregional staging of early colon cancer: A nationwide registry-based study”, whose results confirmed that computed tomography (CT) scan may lead to incorrect staging of colon cancers. Through examination of nationwide Swedish colorectal cancer registry, the authors retrospectively analyzed 4849 patients with colon cancer staged as cT1-2 and all patients with pT1 undergoing surgical resection in 2009–2018 time lapse.

Results showed that 2898 patients (59%) were understaged, coming to pT3-4 histological examination. Among 1474 patients (30%) staged as pN+, 73% (1106) turned out to have been incorrectly staged as cN0-X cases. On the contrary, among 771 CT patients staged as cN+, 403 (52%) were found to be pN0 cases. Out of 3960 patients CT scan staged as cT1-2cN0 cases, 2480 ones (63%) turned out histopathologically understaged either as pN+ or pT3-4. Although outcomes comply with current scientific literature,^2–5 data need careful interpretation.

Recently published results by Morton et al. ⁵ in FOXTROT trial both laid foundations and paved way for new therapeutic approaches in patients with operable colon cancer. Outcomes proved that neoadjuvant therapy (6 weeks oxaliplatin–fluoropyrimidine preoperatively plus 18 postoperatively) in cT3-4, N0-2, M0 colon cancers can be considered safe, as it does not increase perioperative morbidity, allows more R0 surgery and produces histopathologic downstaging. In addition, recurrence rate is lower if compared with control group (adjuvant chemotherapy only) with better disease control (2 years). These data cannot be considered as final results and need careful elucidation. Moreover, if confirmed, they will require greater accuracy in pre-operative radiological diagnosis, in order to avoid both overstaging and understaging of patients.

Improvement of diagnostic pathways, combination of CT scan with other radiological examinations positron emission tomography–computed tomography (PET/CT) or implementation of radiomics studies may all lead to goal fulfillment. ⁶