Protocol for the Examination of Specimens From Patients With Primary Carcinoma of the Colon and Rectum

The College of American Pathologists offers these protocols to assist pathologists in providing clinically useful and relevant information when reporting results of surgical specimen examinations. The College regards the reporting elements in the “Surgical Pathology Cancer Case Summary (Checklist)” portion of the protocols as essential elements of the pathology report. However, the manner in which these elements are reported is at the discretion of each specific pathologist, taking into account clinician preferences, institutional policies, and individual practice.The College developed these protocols as an educational tool to assist pathologists in the useful reporting of relevant information. It did not issue the protocols for use in litigation, reimbursement, or other contexts. Nevertheless, the College recognizes that the protocols might be used by hospitals, attorneys, payers, and others. Indeed, effective January 1, 2004, the Commission on Cancer of the American College of Surgeons mandated the use of the checklist elements of the protocols as part of its Cancer Program Standards for Approved Cancer Programs. Therefore, it becomes even more important for pathologists to familiarize themselves with these documents. At the same time, the College cautions that use of the protocols other than for their intended educational purpose may involve additional considerations that are beyond the scope of this document.This protocol applies to all primary carcinomas of the colon and rectum. Well-differentiated neuroendocrine neoplasms (carcinoid tumors) are not included. The seventh edition TNM staging system for carcinoma of the colon and rectum of the American Joint Committee on Cancer (AJCC) and the International Union Against Cancer (UICC) is recommended.Select a Single Response Unless Otherwise Indicated* Data elements with asterisks are not required. However, these elements may be clinically important but are not yet validated or regularly used in patient management.Tumor Site (note A)__ Cecum__ Right (ascending) colon__ Hepatic flexure__ Transverse colon__ Splenic flexure__ Left (descending) colon__ Sigmoid colon__ Rectum__ Other (specify): ______ Not specified*Specimen Integrity*__ Intact*__ Fragmented*Polyp Size* Greatest dimension: __ cm* Additional dimensions: __ × __ cm*__ Cannot be determined (see Comment)*Polyp Configuration*__ Pedunculated with stalk * Stalk length: __ cm*__ SessileSize of Invasive CarcinomaGreatest dimension: __ cm* Additional dimensions: __ × __ cm__ Cannot be determined (see Comment)Histologic Type (note B)__ Adenocarcinoma__ Mucinous adenocarcinoma__ Signet-ring cell carcinoma__ Small cell carcinoma__ Squamous cell carcinoma__ Adenosquamous carcinoma__ Medullary carcinoma__ Undifferentiated carcinoma__ Other (specify): ______ Carcinoma, type cannot be determinedHistologic Grade (note C)__ Not applicable__ Cannot be determined__ Low grade (well differentiated to moderately differentiated)__ High grade (poorly differentiated to undifferentiated)Microscopic Tumor Extension (note D)__ Cannot be determinedInvasion (deepest): __ Lamina propria __ Muscularis mucosae __ Submucosa __ Muscularis propriaMargins (select all that apply)Deep Margin (Stalk Margin)__ Cannot be assessed__ Uninvolved by invasive carcinoma Distance of invasive carcinoma from margin: __ mm__ Involved by invasive carcinomaMucosal/Lateral Margin__ Not applicable__ Cannot be assessed__ Uninvolved by invasive carcinoma__ Involved by invasive carcinoma__ Involved by adenomaLymph-Vascular Invasion (notes D and E)__ Not identified__ Present__ Indeterminate*Type of Polyp in Which Invasive Carcinoma Arose (note F)*__ Tubular adenoma*__ Villous adenoma*__ Tubulovillous adenoma*__ Traditional serrated adenoma*__ Sessile serrated adenoma*__ Hamartomatous polyp*__ Indeterminate*Additional Pathologic Findings (select all that apply)*__ None identified*__ Inflammatory bowel disease *__ Active *__ Quiescent*__ Other (specify): ____*Ancillary Studies* Specify: ____*__ Not performed*Comment(s): ____Select a Single Response Unless Otherwise Indicated* Data elements with asterisks are not required. However, these elements may be clinically important but are not yet validated or regularly used in patient management.Specimen (select all that apply) (note A)__ Terminal ileum__ Cecum__ Appendix__ Ascending colon__ Transverse colon__ Descending colon__ Sigmoid colon__ Rectum__ Anus__ Other (specify): ______ Not specifiedProcedure__ Right hemicolectomy__ Transverse colectomy__ Left hemicolectomy__ Sigmoidectomy__ Rectal/rectosigmoid colon (low anterior resection)__ Total abdominal colectomy__ Abdominoperineal resection__ Transanal disk excision (local excision)__ Other (specify): ______ Not specified*Specimen Length (if applicable)* Specify: __ cmTumor Site (select all that apply) (note A)__ Cecum__ Right (ascending) colon__ Hepatic flexure__ Transverse colon__ Splenic flexure__ Left (descending) colon__ Sigmoid colon__ Rectosigmoid__ Rectum__ Colon, not otherwise specified__ Cannot be determined (see Comment)Tumor SizeGreatest dimension: __ cm* Additional dimensions: __ × __ cm__ Cannot be determined (see Comment)Macroscopic Tumor Perforation (note G)__ Present__ Not identified__ Cannot be determined*Macroscopic Intactness of Mesorectum (note H)*__ Not applicable*__ Complete*__ Near complete*__ Incomplete*__ Cannot be determinedHistologic Type (note B)__ Adenocarcinoma__ Mucinous adenocarcinoma__ Signet-ring cell carcinoma__ Small cell carcinoma__ Squamous cell carcinoma__ Adenosquamous carcinoma__ Medullary carcinoma__ Undifferentiated carcinoma__ Other (specify): ______ Carcinoma, type cannot be determinedHistologic Grade (note C)__ Not applicable__ Cannot be assessed__ Low grade (well differentiated to moderately differentiated)__ High grade (poorly differentiated to undifferentiated)__ Other (specify): ____*Histologic Features Suggestive of Microsatellite Instability (note I)*Intratumoral Lymphocytic Response (tumor-infiltrating lymphocytes)*__ None*__ Mild to moderate (0–2 per high-power [×400] field)*__ Marked (3 or more per high-power field)*Peritumor Lymphocytic Response (Crohn-like response)*__ None*__ Mild to moderate*__ Marked*Tumor Subtype and Differentiation (select all that apply)*__ Mucinous tumor component (specify percentage: __)*__ Medullary tumor component*__ High histologic grade (poorly differentiated)Microscopic Tumor Extension__ Cannot be assessed__ No evidence of primary tumor__ Intramucosal carcinoma, invasion of lamina propria__ Tumor invades submucosa__ Tumor invades muscularis propria__ Tumor invades through the muscularis propria into the subserosal adipose tissue or the nonperitonealized pericolic or perirectal soft tissues but does not extend to the serosal surface__ Tumor penetrates to the surface of the visceral peritoneum (serosa)__ Tumor is adherent to other organs or structures (specify: ____)__ Tumor directly invades adjacent structures (specify: ____)__ Tumor penetrates to the surface of the visceral peritoneum (serosa) and directly invades adjacent structures (specify: ____)Margins (select all that apply) (note J)Proximal Margin__ Cannot be assessed__ Uninvolved by invasive carcinoma__ Involved by invasive carcinoma__ Intramucosal carcinoma/adenoma not identified at proximal margin__ Intramucosal carcinoma/adenoma present at proximal marginDistal Margin__ Cannot be assessed__ Uninvolved by invasive carcinoma__ Involved by invasive carcinoma__ Intramucosal carcinoma/adenoma not identified at distal margin__ Intramucosal carcinoma/adenoma present at distal marginCircumferential (Radial) or Mesenteric Margin__ Not applicable__ Cannot be assessed__ Uninvolved by invasive carcinoma__ Involved by invasive carcinoma (tumor present 0– 1 mm from margin)If all margins uninvolved by invasive carcinoma: Distance of invasive carcinoma from closest margin: __ mm or __ cm Specify margin: __Lateral Margin (for noncircumferential transanal disk excision)__ Cannot be assessed__ Uninvolved by invasive carcinoma Distance of invasive carcinoma from closest lateral margin: __ mm * Specify location (eg, o’clock position), if possible: ______ Involved by invasive carcinoma * Specify location (eg, o’clock position), if possible: ______ Uninvolved by adenoma__ Involved by adenomaTreatment Effect (applicable to carcinomas treated with neoadjuvant therapy) (note K)__ No prior treatment__ Present *__ No residual tumor (complete response, grade 0) *__ Moderate response (grade 1, minimal residual cancer) *__ Minimal response (grade 2)__ No definite response identified (grade 3, poor response)__ Not knownLymph-Vascular Invasion (note E)__ Not identified__ Present__ IndeterminatePerineural Invasion (note E)__ Not identified__ Present__ IndeterminateTumor Deposits (Discontinuous Extramural Extension)(note L)__ Not identified__ Present__ Indeterminate*Type of Polyp in Which Invasive Carcinoma Arose (note F)*__ None identified*__ Tubular adenoma*__ Villous adenoma*__ Tubulovillous adenoma*__ Traditional serrated adenoma*__ Sessile serrated adenoma*__ Hamartomatous polyp*__ IndeterminatePathologic Staging (pTNM) (note M)TNM Descriptors (required only if applicable) (select all that apply)__ m (multiple primary tumors)__ r (recurrent)__ y (posttreatment)Primary Tumor (pT)__ pTX: Cannot be assessed__ pT0: No evidence of primary tumor__ pTis: Carcinoma in situ, intraepithelial (no invasion)__ pTis: Carcinoma in situ, invasion of lamina propria__ pT1: Tumor invades submucosa__ pT2: Tumor invades muscularis propria__ pT3: Tumor invades through the muscularis propria into pericolorectal tissues__ pT4a: Tumor penetrates the visceral peritoneum__ pT4b: Tumor directly invades or is adherent to other organs or structuresRegional Lymph Nodes (pN)__ pNX: Cannot be assessed__ pN0: No regional lymph node metastasis__ pN1a: Metastasis in 1 regional lymph node__ pN1b: Metastasis in 2 to 3 regional lymph nodes__ pN1c: Tumor deposit(s) in the subserosa, or nonperitonealized pericolic or perirectal tissues without regional lymph node metastasis__ pN2a: Metastasis in 4 to 6 regional lymph nodes__ pN2b: Metastasis in 7 or more regional lymph nodesSpecify: Number examined: __ Number involved: __Distant Metastasis (pM)__ Not applicable__ pM1: Distant metastasis * Specify site(s): ______ pM1a: Metastasis to single organ or site (eg, liver, lung, ovary, nonregional lymph node)__ pM1b: Metastasis to more than one organ/site or to the peritoneum*Additional Pathologic Findings (select all that apply)*__ None identified*__ Adenoma(s)*__ Chronic ulcerative proctocolitis*__ Crohn disease*__ Dysplasia arising in inflammatory bowel disease*__ Other polyps (type[s]): ____*__ Other (specify): ____*Ancillary Studies (select all that apply) (note N)*__ Microsatellite instability (specify testing method: ____) *__ Stable *__ Low *__ High* Immunohistochemistry Studies for Mismatch Repair Proteins *__ MLH1 *__ Intact nuclear positivity, tumor cells *__ Loss of nuclear positivity, tumor cells *__ Pending *__ Other (specify): ____ *__ MSH2 *__ Intact nuclear positivity, tumor cells *__ Loss of nuclear positivity, tumor cells *__ Pending *__ Other (specify): ____ *__ MSH6 *__ Intact nuclear positivity, tumor cells *__ Loss of nuclear positivity, tumor cells *__ Pending *__ Other (specify): ____ *__ PMS2 *__ Intact nuclear positivity, tumor cells *__ Loss of nuclear positivity, tumor cells *__ Pending *__ Other (specify): ____*__ BRAF V600E mutational analysis (specify testing method: ____) *__ Mutant BRAF detected *__ No mutant BRAF detected (wild-type BRAF allele) *__ Other (specify): ____*__ KRAS mutational analysis (specify testing method: ____) *__ Mutant KRAS detected (specify mutation ____) *__ No mutant KRAS detected (wild-type KRAS allele) *__ Other (specify): ____Other, specify: ____*__ Not performed*Comment(s): ____The protocol applies to all carcinomas arising in the colon and rectum.1 It excludes carcinomas of the vermiform appendix and low-grade neuroendocrine neoplasms (carcinoid tumors).The colon is divided as shown in Figure 1. The right colon is subdivided into the cecum and the ascending colon.2 The left colon is subdivided into the descending colon and sigmoid colon (see Table).1The transition from sigmoid to rectum is marked by the fusion of the tenia coli of the sigmoid to form the circumferential longitudinal muscle of the rectal wall approximately 12 to 15 cm from the dentate line. The rectum is defined clinically as the distal large intestine commencing opposite the sacral promontory and ending at the anorectal ring, which corresponds to the proximal border of the puborectalis muscle palpable on digital rectal examination1 (Figure 2). When measuring below with a rigid sigmoidoscope, it extends 16 cm from the anal verge.Tumors located at the border between 2 subsites of the colon (eg, cecum and ascending are as of the that is more 2 subsites are to the same the tumor is as an tumor is as rectal if its than 16 cm from the anal or if part of the tumor is located at the of the rectal tumor is as when between rectum and sigmoid to the is not in the histologic by the is and than cell carcinoma than cell cell neuroendocrine cell cell and carcinomas are grade (see The only histologic of carcinoma that shown to of are cell and cell carcinoma neuroendocrine Medullary carcinoma is a histologic type with of instability of in Medullary carcinoma may or in with colon tumor type is by in or with evidence of neuroendocrine Medullary carcinomas are by tumor (see The otherwise is not part of the of for but a single and used for is into 3 or 4 as a of histologic grade shown by analysis to be a it that tumor grade is an It is that in the of tumor the of to a for analysis as differentiated and moderately differentiated and in the of low-grade into or moderately differentiated in carcinoma is Therefore, in of its and a system for carcinoma grade and is The for on are than or to than invasive that extends through the muscularis mucosae into the defined as in which the is by carcinoma and with but the excludes with or carcinoma carcinoma to the lamina propria or than the muscularis these polyps for (see in polyps by of histologic to the of lymph node metastasis or from residual shown to and are important in the for surgical of shown to be invasion by analysis to be an Invasion of in shown to be an of and of of The of invasion is specific to this issue are and shown by analysis to be of poor The if of the location of these structures is not it is not to from are the or of tumor invasion of be reported in all be between serrated which of and the serrated The serrated may be the for carcinomas with are more in the right colon and are by serrated with of and of nuclear in is an of but one that is with a poor and Perforation of the uninvolved colon proximal to an tumor is with of and from to Perforation is more to in of the surgical is a in the of surgical for rectal in the of and in that excision and the by as as surgical the the visceral to the rectum. the its and all regional and from to to to or and from to in the of a may to of the specimen shown to be a of the of rectal It is to of surgical as of of and It shown that of the of the of the as or and as the of the circumferential the between the tumor and circumferential and the between the tumor and the closest distal are all important of and may be by surgical is evidence that the of the circumferential is a of but is and nonperitonealized surface of the specimen is and the of the is as in the The specimen is to the to the in the to the muscularis the circumferential to the of the surface with than but to the muscularis of of the muscularis propria at the site of the with a of the surface than mm in the distal of the the circumferential of is as may as a of patient a of response to and as a tool for for testing for the in a patient is than of or other and and and and of with in a patient is than in 1 or more with an with 1 of the in a than in 2 or more or with of histologic are defined as of cell or are with and (see and be from or are the tumor not with lymph not only and 3 or more per high-power be with in carcinomas and of may be to the closest to the tumor with of the serosal surface for and other of tumor marked by be in the of the surgical pathology report. The serosal surface does not a surgical to the proximal and distal the circumferential (Figure 3, through be for (Figure 3, or by peritoneum (Figure 3, (see The circumferential the soft tissue closest to the of tumor and is by or of the or analysis that tumor of the circumferential is the in in rectal circumferential in rectal the of by and the of from this the circumferential be in all rectal carcinomas as as with nonperitonealized The between the tumor and circumferential be reported (see The circumferential is if the tumor is more than 1 mm from the nonperitonealized surface but be as if tumor is located 1 mm or from the nonperitonealized surface are with of to 1 tumor a lymph node as as tumor but if circumferential is on this be is the only relevant circumferential in by peritoneum (eg, of this be reported even if tumor does not the serosal to the proximal and distal margins be by longitudinal to the or by to the The from the tumor to the closest may be for anterior these a distal of 2 cm is for and 1 cm may be distal are when the to the closest is cm or of carcinoma arising in a of inflammatory bowel proximal and distal margins be for and in rectal is with tumor response and of the as detected by of the is with a from neoadjuvant be with of the tumor Minimal residual disease shown to a than residual for tumor response a tumor grade shown to with and to be only in the primary lymph node not be in the of in from patient neoadjuvant are to tumor and are not used to or as lymph tumor in pericolic or perirectal from the of the tumor and evidence of residual lymph node but the of the primary carcinoma, are or and are not as lymph by are to more these tumor are with and their be in the surgical pathology report. tumor are in that otherwise be as (tumor to or (tumor to muscularis the primary tumor is not but the is in a as (see the effective for carcinoma, and the of is from the on the The of disease is by the important in protocol the TNM staging system of the and the but does not the use of other staging the to a primary tumor that not The to the of the as to the and is on and a of the primary tumor or to the or of to lymph node and of is by the of the patient or when is not of of TNM or the and and are not the the of primary in a single site and is in in which is or neoadjuvant or and The or is identified by a The or the of tumor present at the of that The is not an of tumor prior to of neoadjuvant a tumor when a and is identified by the in as a staging cells the carcinoma, with or invasive into the lamina to but not through the muscularis mucosae Tumor through the muscularis mucosae into the is as invasion of other organs or structures invasion of other of by of the or (eg, invasion of the sigmoid colon by carcinoma of the is as (Figure a an adjacent organ and the visceral peritoneum are by of tumor from 1 of the large intestine into an adjacent or into the (eg, for a or anal (eg, for a rectal does not the that is adherent to other organs or structures is as However, if tumor is the the tumor be rectal invasion of the is as invasion of the is as in or does not the by tumor cells by analysis to a on as does invasion of adjacent organs be without and cells identified in serosal in as as of as by histologic the of for may to the are to serosal by Tumor present at the serosal surface with inflammatory tumor cells on the serosal surface the with of the visceral of are with that serosal with than invasion of adjacent from a large of more than colon that of the visceral peritoneum a to than invasive carcinomas for each of Therefore, of the in the seventh edition of the Cancer Staging to these regional lymph for the subsites of the large intestine (Figure are as anterior right right right left left rectal sigmoid left sigmoid sigmoid lateral sacral the sigmoid are pericolic and their is as or to the lymph the lateral sacral promontory rectal and rectal Metastasis in the or is as or lymph are to be lymph may be for of and of are directly to the of the surgical in all regional and the of the specimen in and all regional lymph for It that 12 lymph be the minimal from a specimen the the of at 12 lymph in a surgical the for colon in the (see evidence that this be as the the of the the that metastasis be that of or all it shown that is to lymph node in shown that of of lymph is with an in a of by the lymph node from the specimen by the pathologist, or of lymph from specimen is on and patient (eg, and the of in a but the and of the in and lymph in the specimen are Lymph may be more to in from are or or neoadjuvant it shown that metastasis in is in lymph mm in for lymph is on of than 12 lymph are the specimen for additional lymph with or without be The pathology the of lymph and the by Data are to use of tissue or of lymph in large lymph be as regional to the location of the Metastasis to nonregional lymph is as metastasis and as tumor in the without histologic evidence of residual lymph node tissue is as a tumor or and is not a lymph tumor may with or lymph the of lymph node tumor are as is defined as tumor measuring than mm but than or to mm in are as or in lymph or at tumor cells are defined as single tumor cells or of tumor cells measuring mm or by as and are as the of a single in a single a single or of is The of lymph by or be of regional lymph is to and histologic and are to to or of the use of as are for of regional lymph of the is as for in which are the only evidence of staging is surgical of the primary Pathologic staging on of the of or not the primary tumor a tumor is not for (eg, when and if the and or the of the tumor be the for and staging without of the primary of in in carcinomas is important for of of for approximately of all and of the tissue for is if of the in the (note are that in colon is with and may as a of response to these for testing are not and not as of from with to not an are to testing but not for an be in approximately of The of testing be by it on as than or with a of (eg, or testing be used to for with an may a mutation in one of (eg, or and may to testing for may in a of the and in the of in of to and and testing is with at or a of that use a of 3 and 3 for that may and for with an a a more and in testing use a for testing that of in a tumor by analysis that the used for the analysis be from a portion of the tumor that approximately or more tumor pathologists of the tumor for that at this of testing is in with testing for the results of and testing are (eg, with or with the that the same used for and testing and that testing are through the College of American Pathologists and other are to that the are as the results of and testing be into the surgical pathology for the and an of the of these not this testing be for that an this information the that is to a mutation (eg, a patient tumor of MSH2 and MSH6 but of MLH1 and PMS2 is to an MSH2 of of and PMS2 is the testing used for to these are in the of tumor cells is as and it is for to be of be only if is in as the of or Intact of all 4 that are but does not as approximately of may a mutation in that to a with in may to a but this is Loss of of MLH1 may be to or of the in testing is for this a specific BRAF mutation is present in but not Loss of MSH2 PMS2 is with of MLH1 and is only if MLH1 is MSH6 is to for in the V600E in BRAF may be for that as this mutation in but not in of BRAF mutational analysis as a testing in with may be a of with for testing is not of the mutation shown to be with of response to at the as and for KRAS mutational analysis are from the American for are that all with carcinoma are for their tumor for KRAS is not for mutation in KRAS 12 or