Is neoadjuvant chemoradiotherapy sufficient in patients with advanced rectal malignancy and positive extra‐mesorectal lateral lymph nodes?

Abstract

Aim There is current debate about the optimal management of lateral pelvic lymph nodes (LPLNs) in rectal cancer between Western and Eastern centres. This paper aims to report the rate of histologically proven positive LPLNs in a group of patients undergoing the conventional Western approach to primary and recurrent rectal cancer. Method A retrospective cohort review of all patients who underwent LPLN dissection at Royal Prince Alfred Hospital in Sydney, Australia. This included patients who underwent pelvic exenteration who had LPLNs excised either en bloc for laterally invasive or recurrent tumours or as part of selective node dissection for suspicious lymph nodes on preoperative imaging. Histopathological results for these patients were compared with node status at preoperative imaging. Results Seventy‐one patients satisfied the inclusion criteria. Of those patients with positive nodes on histology, 27% (9/33) with radiologically positive LPLNs were treated with preoperative radiotherapy and 75% (9/12) with radiologically positive LPLNs were not treated with preoperative radiotherapy (P = 0.004). None of the 12 patients with radiologically negative nodes treated with radiotherapy had positive nodes; 25% (3/12) of the patients with radiologically negative nodes who were not treated with radiotherapy had positive nodes. Fifty‐three per cent of patients developed postoperative complications. Conclusion Our study suggests that in patients with radiologically positive LPLNs chemoradiotherapy may not be enough to sterilize these extra‐mesorectal lymph nodes as a large proportion (27%) will have residual viable adenocarcinoma cells. In patients with radiologically negative LPLNs, however, the addition of chemoradiotherapy may serve to adequately sterilize these lymph nodes without the need for prophylactic LPLN dissection.

Rectal cancer lateral pelvic sidewall lymph nodes: a review of controversies and management

“…The longer‐term significance and oncological outcomes were not considered in this review. These findings were recently corroborated in the most advanced cancers requiring exenteration and undergoing concurrent LPND; clinically positive nodes were associated with a 75 per cent risk of histopathological positivity if NCRT was not used, and a 25 per cent risk of histopathological positivity despite the use of NCRT 30 . Taken together, these results suggest that, although NCRT reduces the risk of local recurrence overall, there are groups of patients in whom this may not be sufficient to achieve local control and targeted LPND for suspicious nodes after NCRT may be beneficial.…”

“…This found a non-significant trend towards improved survival and reduced local recurrence after LPND; the full study data remain unpublished. A summary of relevant studies is presented in Table 1 21,22,[26][27][28]30,[32][33][34][35]39,40 .…”

Management of Clinically Involved Lateral Lymph Node Metastasis in Locally Advanced Rectal Cancer: A Radiation Dose Escalation Study

“…According to previous studies, baseline LLNs SA cut-off from 5 to 10 mm were adopted as the clinically positive standard before nCRT (13,(23)(24)(25). In a recent large-scale study conducted The bold type indicates that the P value is statistically significant.…”

Outcome of lateral pelvic lymph node dissection with total mesorectal excision in treatment of rectal cancer: A systematic review and meta-analysis

“…Neoadjuvant therapy, whether radiotherapy, chemotherapy, or a combination of both, serves to reduce the tumor burden in advance of curative surgery and address the extra-mesorectal lateral pelvic lymph nodes (LPLN). 2,3 A controversial aspect regarding the treatment of locally advanced rectal cancer is the role of LPLN dissection (LPLND). 4 Although guidelines followed in the West have recommended the liberal use of neoadjuvant therapy rather than LPLND for locally advanced rectal carcinoma, the Japanese guidelines have routinely employed LPLND with or without neoadjuvant treatment.…”