Endometrium

Protocol applies to all carcinomas of the endometrium.

 

Procedures

• Cytology

• Biopsy

• Curettage

• Hysterectomy

This protocol is intended to assist pathologists in providing clinically useful and relevant information as a result of the examination of surgical specimens. Use of this protocol is intended to be entirely voluntary. If equally valid protocols or similar documents are applicable, the pathologist is, of course, free to follow those authorities. Indeed, the ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of the individual circumstances presented by a specific patient or specimen.

 

It should be understood that adherence to this protocol will not guarantee a successful result. Nevertheless, pathologists are urged to familiarize themselves with the document. Where a physician chooses to deviate from the protocol based on the circumstances of a particular patient or specimen, the physician is advised to make a contemporaneous written notation of the reason for the procedure followed.

 

The College recognizes that this document may be used by hospitals, attorneys, managed care organizations, insurance carriers, and other payers. However, the document was developed solely as a tool to assist pathologists in the diagnostic process by providing information that reflects the state of relevant medical knowledge at the time the protocol was first published. It was not developed for credentialing, litigation, or reimbursement purposes. The College cautions that any uses of the protocol for these purposes involve considerations that are beyond the scope of this document.

 

I. Cytologic material                  back     Top     Main Page

      A.  Clinical Information

            1.   Patient identification

                  a.   Name

                  b.   Identification number

                  c.   Age (birth date)

            2.   Responsible physician(s)

            3.   Date of procedure

            4.   Other clinical information

                  a.   Relevant history

                        (1)  previous diagnosis, treatment or procedure (Note A)

                        (2)  menstrual history, including date of last normal period

                        (3)  previous/current pregnancy history

                        (4)  exogenous hormones, including type and duration

                  b.   Relevant findings (e.g. intraoperative, hysteroscopic, radiologic, laboratory)

                  c.   Clinical diagnosis                                                                     

                  d.   Procedure

                        (1)  cervical smear

                        (2)  vaginal pool aspiration

                        (3)  endocervical or direct endometrial sampling (specify technique)

                        (4)  peritoneal washing

                        (5)  fine needle aspiration (specify and describe site)

                        (6)  scraping of diaphragmatic or peritoneal surface (specify if gross lesion present)

B.   Macroscopic Examination

            1.   Specimen

                  a.   Unfixed/fixed (specify fixative)

                  b.   Number of slides received, if appropriate

                  c.   Quantity and appearance of fluid specimens, if appropriate

                  d.   Other (e.g. cytologic preparation from tissue)

                  e.   Results of intraprocedural consultation

            2.   Material submitted for microscopic evaluation (e.g. smear, cytocentrifuge, touch or filter preparation, cell block)

            3.   Special studies (specify) (e.g. cytochemistry, immunocytochemistry, DNA analysis [specify type], morphometry, cytogenetic analysis)

      C.  Microscopic evaluation

            1.   Adequacy of specimen (if unsatisfactory for evaluation, specify reason) (Note B)

            2.   Tumor, if present

                  a.   Histologic type of tumor, if possible (Note C)

                  b.   Other characteristics (e.g. degree of differentiation)

            3.   Additional pathologic findings, if present

            4.   Results/status of special studies (specify)

            5.   Comments

                  a.   Correlation with intraprocedural consultation, as appropriate

                  b.   Correlation with other specimens, as appropriate

                  c.   Correlation with clinical information, as appropriate

 

II. Biopsy and Curettage              back     Top     Main Page

 

      A.  Clinical Information

            1.   Patient identification

                  a.   Name

                  b.   Identification number

                  c.   Age (birth date)

            2.   Responsible physician(s)

            3.   Date of procedure

            4.   Other clinical information

                  a.   Relevant history

                        (1)  previous diagnosis, treatment or procedure (Note A)

                        (2)  menstrual history, including date of last normal period

                        (3)  previous/current pregnancy history

                        (4)  exogenous hormones, including type and duration

b.   Relevant findings (e.g. intraoperative, hysteroscopic, radiologic, laboratory)

c.   Clinical diagnosis

d.   Procedure (e.g. biopsy, fractional curettage, polypectomy)

e.   Site of specimen (e.g. endometrium, endocervix)

 

      B.   Macroscopic Examination

            1.   Specimen

                  a    Unfixed/fixed (specify fixative)

                  b.   Size (if multiple pieces, aggregate dimensions or size range of pieces: distinguish tissue from blood, if possible)

c.   Results of intraoperative consultation

2.   Tumor, if discernible (e.g. consistency or necrosis)

                  a.   Dimensions

                  b.   Other descriptive features

            3.   Tissue submitted for microscopic evaluation (Note D)

            4.   Special studies (specify) (e.g. estrogen/ progesterone receptors, immunohisto-chemistry, flow cytometry, morphometry, cytogenetic analysis)

      C.  Microscopic Examination

            1.   Adequacy of specimen (if inadequate for evaluation, specify reason) (Note E)

            2.   Tumor

                  a.   Histologic type(s) (Note C)

                  b.   Histologic grade (Note F)

                  c.   Extent (proportion of specimen involved or dimensions if small and measurable)

            3.   Additional pathologic findings, if present

                  a.   Hyperplasia (specify type) (Note C)

                  b.   Metaplasia (specify type)

                  c.   Others(s)

            4.   Results/status of special studies (specify)

            5.   Comments

                  a.   Correlation with intraoperative consultation, as appropriate

                  b.   Correlation with other specimens, as appropriate

                  c.   Correlation with clinical information, as appropriate

III. Hysterectomy            back     Top     Main Page

      A.  Clinical Information

            1.   Patient identification

                  a.   Name

                  b.   Identification number

                  c.   Age (birth date)

            2.   Responsible physician(s)

            3.   Date of procedure

            4.   Other clinical information

                  a.   Relevant history

                        (1)  previous diagnosis, treatment or procedure (Note A)

                        (2)  menstrual history, including date of last normal period

                        (3)  previous/current pregnancy history

                        (4)  exogenous hormones, including type and duration

                  b.   Relevant findings (e.g. intraoperative, hysteroscopic, radiologic, laboratory)

c.   Clinical diagnosis

d.   Procedure (e.g. hysterectomy with bilateral salpingo-oophorectomy and pelvic lymph node sampling)

 

      B.   Macroscopic Examination

            1.   Specimen

                  a.   Organ(s)/tissue(s) included

                  b.   Unfixed/fixed (specify fixative)

                  c.   Number of pieces

                  d.   Dimensions (three)

                  e.   Orientation (if indicated by surgeon)

                  f.    Results of intraoperative consultation

            2.   Uterine tumor

                  a.   Location (e.g. fundus/right cornu/isthmus)

                  b.   Dimensions (three)

                  c.   Descriptive characteristics (e.g. exophytic/necrosis)

                  d.   Distance from margins

                  e.   Estimated extent of invasion (Note G)

            3.   Uninvolved uterus

                  a.   Dimensions

                  b.   Appearance of:

                        (1)  endometrium

                        (2)  myometrium, including thickness

                        (3)  serosa

                        (4)  cervix

                  c.   Additional pathologic findings, if present

            4.   Fallopian tubes

                  a.   Tumor, if present

                        (1)  dimensions

                        (2)  location and relation to uterine tumor

                  b.   Resection margins, as appropriate

                  c.   Other pathologic findings, if present

            5.   Ovary(ies)

                  a.   Tumor, if present (see Ovary protocol)

                        (1)  dimensions

                        (2)  location and relation to uterine tumor

                  b.   Resection margins, as appropriate

                  c.   Other pathologic findings, if present

            6.   Regional lymph nodes

                  a.   Location (if specified by surgeon)

                  b.   Number at each location

                  c.   Descriptive features of grossly involved nodes at each location

            7.   Other organs and tissues, including biopsy specimens with location specified by surgeon

                  a.   Descriptive features

                  b.   Tumor, if present

                        (1)  dimensions

                        (2)  location and relation to uterine tumor

                  c.   Resection margins, as appropriate

                  d.   Other pathologic findings

            8.   Tissues submitted for microscopic evaluation

                  a.   Carcinoma, including section(s) to demonstrate:

                        (1)  deepest invasion of myometrium (See Figure 1)

                        (2)  distance from serosa (if thickness of myometrium or depth of tumor is not known, extent may be specified as distance in mm from the serosa)

                        (3)  most inferior level of involvement

                        (4)  interface with adjacent uninvolved endometrium and myometrium

                  b.   Uninvolved endo-myometrium

                  c.   Cervix including endocervical and exocervical portions

                  d.   Resection margin, as appropriate

                        (1)  cervical or vaginal

                        (2)  parametrial

                        (3)  other(s)

                  e.   Additional uterine lesions, if present

                  f.    Lymph nodes — at least one section of each

                  g.   Staging biopsy specimens — one section of each

                  h.   Omentum — several sections if grossly negative; otherwise representative sampling

                  i.    Frozen tissue fragment(s) (unless saved for special studies)

                  j.    Other organs and tissues

                        (1)  Tumor present — sections adequate to demonstrate:

                              i.    histologic type and grade of tumor

                              ii.    relation to uterine tumor and resection margins (if appropriate)

                        (2)  Tumor absent

                              i.    routine sections

                              ii.    sections through previous site of tumor, if discernible

                        (3)  Other pathologic lesions, as appropriate

            9.   Special studies (specify) (e.g. DNA ploidy, hormone receptors, oncogene evaluation)

 

      C.  Microscopic Examination

            1.   Uterus

                  a.   Tumor

                        (1)  histologic type (Note C)

                        (2)  histologic grade (Note F)

                        (3)  extent of invasion (Note G)

                        (4)  blood/lymphatic vessel invasion

                  b.   Additional pathologic findings, if present

                        (1)  hyperplasia (specify type) (Note C)

                        (2)  endometrial intraepithelial carcinoma (EIC – particularly associated with serous carcinomas)

                        (3)  adenomyosis, with/without tumor (extension of tumor into adenomyosis is not considered true myometrial invasion but is reported separately)

                  c.   Margins

                        (1)  cervical or vaginal

                        (2)  parametrial

                        (3)  other(s)

            2.   Regional lymph nodes

                  a.   Number at each site (Note G)

                  b.   Number involved by tumor at each site

                  c.   Additional findings (e.g. glandular inclusions)

            3.   Other organs and tissues including staging biopsy specimens (specify)

                  a.   Tumor, if present (Note G)

                        (1)  histologic type, if different from main tumor

                        (2)  histologic grade, if different from main tumor

                        (3)  consistent with

                              i.    direct extension

                              ii.    metastasis

                              iii.   separate primary tumor

                        (4)  site

                        (5)  extent

                        (6)  relation to resection margins

                  b.   Additional pathologic findings, if present

                  c.   Results/status of special studies (specify)

            4.   Comments

                  a.   Correlation with intraoperative consultation, as appropriate

                  b.   Correlation with other specimens, as appropriate

                  c.   Correlation with clinical information, as appropriate

 

EXPLANATORY NOTES

A.  Previous Diagnoses            back     Top     Main Page

Slides of previous pertinent specimens should be made available to the pathologist if their review is deemed essential by the surgeon or pathologist for optimal interpretation of the present specimen.

B.  Adequacy of Cytology Sample for Microscopic Evaluation                        back     Top     Main Page

If a cytologic sample is procured by a transvaginal procedure other than direct endometrial sampling, the absence of endometrial cells does not signify specimen inadequacy.

C.  Histologic Type             back     Top     Main Page

The World Health Organization (WHO) Histologic Classification of Endometrial Carcinoma and Hyperplasia(1) is shown below.

 

Carcinoma

•     Endometrioid carcinoma

      -     Adenocarcinoma

            -     Secretory (variant)

            -     Ciliated cell (variant)

      -     Adenocarcinoma with squamous
            differentiation

            -     (Adenoacanthoma)

            -     (Adenosquamous carcinoma)

•     Serous adenocarcinoma

•     Clear cell adenocarcinoma

•     Mucinous adenocarcinoma

•     Squamous cell carcinoma

•     Mixed carcinoma*

•     Undifferentiated carcinoma

 

*A carcinoma (other than adenocarcinoma with squamous differentiation) in which one or more additional types of tumor account for at least 10% of the entire tumor. The diagnosis is optimally made on examination of a hysterectomy specimen, but if only a smaller specimen is available, any amount of a second tumor category suffices for the diagnosis. When a carcinoma is classified as “mixed,” the major and minor types and their relative proportions should be specified.

 

Hyperplasia

•     Simple

•     Complex (adenomatous)

 

Atypical hyperplasia

•     Simple

•     Complex (adenomatous with atypia)

 

D. Tissue Submitted for Microscopic Evaluation                    back     Top     Main Page

All biopsy or curettage tissue is generally submitted, often in an embedding bag. The blood may be removed before submission either with a clean forceps or by gentle washing in saline solution.

 

E.   Adequacy of Biopsy/Curettage Material                               back     Top     Main Page

It should be noted that adequacy varies both with the procedure (e.g. more tissue expected from a curettage than an outpatient biopsy) and the diagnosis (e.g. atrophic endometrium generally yields scanty specimens even at curettage).  If the tissue obtained is not representative of functioning endometrium (e.g. endocervix, lower uterine segment, or surface endometrium only), this fact should be specified.

 

F.   Histologic Grading              back     Top     Main Page

The glandular component of all endometrioid carcinomas is graded as follows(1):

 

•     Grade X:    Cannot be assessed

•     Grade 1:     5% or less non-squamous solid
                        growth pattern

•     Grade 2:     6%-50% non-squamous solid
                        growth pattern

•     Grade 3:     More than 50% of a non-squamous
                        solid growth pattern

 

Notable nuclear atypia inappropriately severe for the architectural grade of the tumor raises the grade of otherwise Grade 1 tumors by one.

 

Comment: Serous, clear cell, and undifferentiated carcinomas are high-grade and need not be graded. No universally accepted criteria exist for grading of mucinous adenocarcinomas, but if graded by the same criteria listed above for endometrioid adenocarcinomas, they are almost all Grade 1. The squamous component of endometrioid adenocarcinoma with squamous differentiation is generally not graded.

 

G. TNM and FIGO Staging of Endometrial Carcinoma(2,3)                                 back     Top     Main Page

 

The TNM Staging System for endometrial cancer endorsed by the American Joint Committee on Cancer (AJCC) and the International Union Against Cancer (UICC) and the parallel system formulated by the International Federation of Gynecology and Obstetrics (FIGO) are recommended as shown below.

TNM*             FIGO               Definition

Category          Stage   

 

TX                   (--)                   Primary tumor cannot be

                                                assessed

T0                    (--)                   No evidence of primary tumor

Tis                    0                      Carcinoma in situ

T1                    I                       Tumor confined to corpus

                                                uteri

T1a                  IA                    Tumor limited to

                                                endometrium

T1b                  IB                    Tumor invades up to or less

                                                than one half of the

                                                myometrium

T1c                  IC                    Tumor invades to more than

                                                one half of the myometrium

T2                    II                      Tumor invades cervix, but

                                                does not extend beyond uterus

T2a                  IIA                   Endocervical glandular

                                                involvement only

T2b                  IIB                   Cervical stromal invasion

T3                    III                    Local and/or regional spread

                                                as specified in T3a, b, N1 and

                                                FIGO IIIA, B and C below

T3a                  IIIA                  Tumor involves serosa and/or

                                                adnexa (direct extension or

                                                metastasis) and/or cancer

                                                cells in ascites or peritoneal

                                                washings

T3b                  IIIB                  Vaginal involvement (direct

                                                extension or metastasis)

N1                   IIIC                  Metastasis to the pelvic and/or

                                                Para-aortic lymph nodes

T4**                IVA                 Tumor invades bladder

                                                mucosa** and/or bowel

                                                mucosa**

M1                   IVB                  Distant metastasis***

 

*By AJCC/UICC convention, the designation “T” refers to a primary tumor that has not been previously treated. The symbol “p” refers to the pathologic classification of the TNM, as opposed to the clinical classification and is based on gross and microscopic examination.  pT entails a resection of the primary tumor or biopsy adequate to evaluate the highest pT category; pN entails removal of nodes adequate to validate lymph node metastasis; and pM implies microscopic examination of distant lesions.  Clinical classification (cTNM) is usually carried out by the referring physician before treatment during initial evaluation of the patient or when pathologic classification is not possible.

 

Tumor Remaining in the Patient

Tumor remaining in a patient after therapy with curative intent (e.g., surgical resection for cure) is categorized by a system known as R classification, shown below. 

 

RX                   Presence of residual tumor cannot

                        be assessed

R0                    No residual tumor

R1                    Microscopic residual tumor

R2                    Macroscopic residual tumor.

 

For the surgeon, the R classification may be useful to indicate the known or assumed status of the completeness of a surgical excision.  For the pathologist, the R classification is relevant to the status of the margins of a surgical resection specimen.  That is, tumor involving the resection margin on pathologic examination may be assumed to correspond to residual tumor in the patient and may be classified as macroscopic or microscopic according to the findings at the specimen margin(s).

 

Tumor Remaining in a Specimen

In contrast, tumor remaining in a resection specimen from a patient who has undergone previous (neoadjuvant) treatment of any type (radiation therapy alone, chemotherapy therapy alone, or any combined modality treatment) is codified by the TNM using a prescript “y” (e.g., ypT1).  Thus, yTNM indicates the post-treatment status of the tumor.  For many neoadjuvant therapies, the classification of residual disease may be a strong predictor of postoperative outcome.  In addition, the ypTNM classification provides a standardized framework for the collection of data needed to accurately evaluate new neoadjuvant therapies.

 

Locally Recurrent Tumor

In contrast to “residual” tumor, classification of a tumor as “recurrent” requires a documented disease-free interval after definitive therapy.  Recurrent tumor may also be classified according to the TNM categories, but the prefix “r” (e.g., rpT1) is used to indicate the recurrent status of the tumor. 

 

**Presence of bullous edema is not sufficient evidence to classify a tumor as T4.

 

***Excludes metastasis to vagina, pelvic serosa, or adnexa; includes metastasis to intra-abdominal lymph nodes other than para-aortic and/or inguinal lymph nodes.

 

Regional Lymph Nodes (N)† : TNM Staging System

NX                  Regional lymph nodes cannot be assessed

N0                   No regional lymph node metastasis

N1                   Regional lymph node metastasis

 

†Regional lymph nodes include the pelvic, hypogastric (obturator), common iliac, external iliac, internal iliac, parametrial, sacral, and para-aortic lymph nodes.

 

Distant Metastasis (M): TNM Staging System

MX                  Distant metastasis cannot be assessed

M0                   No distant metastasis

M1                   Distant metastasis

 

AJCC/UICC TNM STAGE GROUPINGS and FIGO STAGES

AJCC/UICC                                       FIGO

 

Stage 0             Tis        N0       M0      

Stage IA           T1a      N0       M0       Stage IA

Stage IB           T1b      N0       M0       Stage IB

Stage IC           T1c      N0       M0       Stage IC

Stage IIA         T2a      N0       M0       Stage IIA

Stage IIB          T2b      N0       M0       Stage IIB

Stage IIIA        T3a      N0       M0       Stage IIIA

Stage IIIB        T3b      N0       M0       Stage IIIB

Stage IIIC        T1        N1       M0       Stage IIIC

                        T2        N1       M0

                        T3a,b   N1       M0

Stage IVA        T4        Any N  M0       Stage IVA

Stage IVB        Any T   Any N  M1       Stage IVB

 

REFERENCES                                                                                  back     Top     Main Page

1.     Scully RE, Bonfiglio TA, Kurman RJ, Silverberg SG, Wilkinson EJ. Histological Typing of Female Genital Tract Tumours. In: World Health Organization: International Histological Classification of Tumours. New York: Springer-Verlag; 1994.

2.     Fleming ID, Cooper JS, Henson DE, et al. eds. AJCC Manual for Staging of Cancer. 5th ed. Philadelphia, PA: Lippincott Raven; 1997.

3.     Pettersson F. Annual report of the results of treatment in gynecological cancer. Stockholm: International Federation of Gynecologic and Obstetrics; 1991.

 

BIBLIOGRAPHY

•      Silverberg SG, Kurman RJ. Tumors of the Uterine Corpus. In: Atlas of Tumor Pathology. 3rd series. Fascicle 3. Washington, DC: Armed Forces Institute of Pathology; 1992.

•      Silverberg SG, Tabbara SO. The Uterine Corpus. In: Silverberg SG, ed. Principles and Practice of Surgical Pathology. 3rd ed. New York: Churchill Livingstone; 1997:2459-2524.

 

Author:

Steven G. Silverberg, MD

 

©2000. College of American Pathologists (CAP). All rights reserved. None of the contents of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise) without prior written permission of the publisher.

 

Expires as CAP policy in May 2001. A year prior, the protocol will be reviewed and updated.

 

Contributors:

CAP Cancer Committee; Donald E. Henson, MD; Enrique Hernandez, MD;  Maureen Killacky, MD; Beverly B. Kramer, MD; Rachelle Lanciano, MD; Janice M. Lage, MD; Stanley J. Robboy, MD; Stephen G. Ruby, MD; Robert E. Scully, MD; Richard Zaino, MD

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