It's important to remember what is removed in a mesorectal resection. Only the mesorectal lymph nodes are removed. The external iliac and internal iliac nodes are not removed and in fact cannot even be selectively removed after preoperative therapy because they usually respond. The reason for this i...

I think typically people only extend anteriorly to cover the external iliacs when there is evidence of adjacent gynecologic/gastrointestinal organ involvement (bladder, prostate, or vagina/uterus), and not usually based on nodal positivity. There are data to indicate that one can lower the superior ...

re the last part of the question.  I would not electively cover the common iliac region.  However, if a clinically postive node were identified in that area, I would cover it and boost it, much as Chris advocates.  A node at the level of the common iliac vessels might actually be a hi...

More data suggesting an elevated risk of lateral lymph node recurrence in the absence of dissection if cN+ by MRI: pmid 30403572 (JCO 2019).  The risk is upwards of 30% if >= 10 mm on short axis (Table 2).  There is clear rationale for dose escalation in this situation but am curious to...