Quirke's Method For Dissecting Colorectal Adenocarcinoma
Posted Nov 04 2009 10:02pm
Quirke's Method For Dissecting Colorectal Adenocarcinoma. This is Philip Quirke's method for assessing colorectal adenocarcinoma as demonstrated for the MRC-CR07 trial participants. The first step is to assess the colon for completeness of mesorectal excision. A grade of 1, 2 or 3 (3 is best) is given. Gross pathologic assessment of completeness of mesorectal excision (i.e. complete excision of the rectal mesentery or mesorectal fat pad) be reported on all rectal cancers. The purpose of this is to identify those patients who are more likely to recur postop., giving prognostic information and thus affecting followup . There is no doubt that complete mesorectal excision will reduce local recurrence rates (from 30-40% without TME, down to 3.7% with TME (as reported by Heald).
Quirke's graded assessment of completeness of mesorectal excision (MRC trial) 3-Good: Intact mesorectum with only minor irregularities of a smooth mesorectal surface. No defect is deeper then 5 mm. No coning on the specimen. Smooth CRM on slicing.
2-Moderate: moderate bulk to the mesorectum but irregularity of the mesorectal suface. Moderate coning of the specimen towards the distal margin. At no site is the m.propria visible with the exception of the insertion of levator muscles. Moderate irregularity of CRM.
1-Poor: Little bulk to mesorectum with defects down onto m.propria and/or very irregular cirumferential resection margin.
Notes - Coning refers to the tendency for the surgeon to cut towards the colon and breachthe mesorectal envelope as he goes distal rather than staying outside the mesorectal plane. This gives a tapered conical appearance rather than a bulky distal mesorectal fat pad. This can also lend a ragged appearance to the specimen since the surgeon may realize his mistake and go outside the mesorectum to find the correct plane once again, leaving gashes in what should be a smooth mesorectal surface. - Is it possible for the entire mesorectum to be removed even though it has a ragged appearance? Yes, but it doesn't matter. Once the mesorectum has been violated the risk for spillage of tumour from lymphatics exists. A ragged specimen without a smooth surface must therefore be a grade 2.