Curative resection in signet ring cancer is difficult. Even when the primary tumor appears to be localized without nodal or peritoneal spread, tumors often prove to be more advanced than originally thought on the basis of radiologic techniques or intraluminal ultrasound. More extensive surgery than intersphincteric resection therefore appears to be advisable.

While while I agree dfs and overall survival for signet rings are suboptimal

in terms of local recurrence after r0 resection, comparative data is scarce

while these patients are likely to have to distant metastases, this is probably not a contraindication to sphincter saving to isr

in India young patients with signet ring are high and likely to default treatment if aper offered where technically Ist is possible

havent seen any literature so far, however original paper by schiesel  does state this to be a contraindication 

I woluld not perform intersphincteric resection in signet-ring or poorly differentiated  cancer since there is too high a risk of local recurrence. What is more, the preoperative radiation or chemoradiation should be applied to improve local control after curative surgery.

our experience is similar to what was mentioned by Dr Piotr,Local recurrence is high with ISR,and these pts in India are younger.However chemo rad followed by ISR with informed consent or APR is our practice.