Gallbladder

Protocol applies to all carcinomas of the gallbladder including those showing focal endocrine differentiation.

Procedures

• Cholecystectomy

• Cholecystectomy with Wedge Resection

• Cholecystectomy with Lymph Node Dissection

 

      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. Resection (cholecystectomy)                 back     Top     Main Page

 

      A.  CLINICAL INFORMATION

1.   Patient identification

a.   Name

b.   Identification number

c.   Age (birth date)

d.   Gender

2.   Responsible physician(s)

3.   Date of procedure

4.   Other clinical information

a.   Relevant history (e.g. right upper abdominal pain)

b.   Relevant findings (e.g. ultrasound, other imaging studies)

c.   Clinical diagnosis (e.g. chronic cholecystitis)

d.   Procedure (e.g. abdominal cholecystectomy)

e.   Operative findings

 

 

      B.   MACROSCOPIC EXAMINATION

1.   Specimen

a.   Organ(s)/tissue(s) received (Note A)

b.   Unfixed/fixed (specify fixative)

c.   Previously opened

d.   Orientation (if indicated by surgeon)

e.   Dimensions (measure attached tissues individually)

f.    Gallstones (number, type) (Note B)

g.   Results of intraoperative consultation

2.   Tumor

a.   Location (fundus/body/neck)

b.   Configuration (Note C)

c.   Dimensions (include entire tumor)

d.   Descriptive features (e.g. color, consistency, necrosis)

e.   Extent of invasion (Note D)

3.   Margins

a.   Cystic duct

b.   Liver bed

c.   Other(s) (as appropriate)

4.   Regional lymph nodes

a.   Location (if possible)

b.   Number

5.   Additional pathologic findings, if present

6.   Tissues submitted for microscopic evaluation

a.   Tumor, including:

(1)  point of deepest penetration

(2)  overlying serosa

(3)  interface with adjacent tissue

b.   Gallbladder uninvolved by tumor

c.   Margin of cystic duct

d.   Liver (including margin of resection closest to tumor)

e.   All lymph nodes

f.    Other lesion(s)

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

h.   Other tissue(s)/organ(s)

7.   Special studies (specify) (e.g. histochemistry, immunohistochemistry, morphometry, DNA analysis, cytogenetic analysis)

 

 

      C.  MICROSCOPIC EVALUATION

1.   Tumor (Note E)

a.   Histologic type (Note F)

b.   Histologic grade (Note G)

c.   Depth of invasion (Note D)

d.   Blood/lymphatic vessel invasion (Note H)

e.   Perineural invasion (Note I)

2.   Margins

a.   Cystic duct

b.   Liver bed

c.   Other(s) (as appropriate)

3.   Additional pathologic findings, if present (Note J)

a.   Dysplasia

b.   Intestinal metaplasia

c.   Other(s)

4.   Regional lymph nodes (Note K)

a.   Number

b.   Number involved by tumor (specify location, if possible)

5.   Other organ(s) or structure(s) (specify sites) (Note K)

a.   Involvement by tumor by direct extension

b.   Metastasis involvement

6.   Other tissue(s)/organ(s)

7.   Results/status of special studies (specify)

8.   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.  Application         back     Top     Main Page

The protocol applies only to carcinomas of the gallbladder including those showing endocrine differentiation but excludes carcinoid tumors. More than 98% of malignant tumors of the gallbladder are carcinomas.

 

B.  Gallstones            back     Top     Main Page

The presence or absence of stones should be reported. Gallbladder cancer occurring in the absence of stones may result from an anomalous choledocho-pancreatic junction or from an association with chronic inflammatory bowel disease.

 

C.  Configuration             back     Top     Main Page

Configuration types include exophytic, endophytic, or diffusely infiltrating. Since papillary carcinomas have a favorable prognosis, these lesions should be specifically reported.(1)

 

D. TNM and Stage Grouping                back     Top     Main Page

The TNM Staging System for carcinomas of the gallbladder of the American Joint Committee on Cancer/International Union Against Cancer is recommended by the protocol and shown below.(2,3) The TNM does not apply to carcinoid tumors or to sarcomas. Carcinomas of the gallbladder are staged according to their depth of penetration into the wall and extension to adjacent organs, and the extent of invasion correlates inversely with survival.(1)

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 a patient after definitive therapy (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).

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.

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.

Primary Tumor (T)

TX                   Primary tumor cannot be assessed

T0                    No evidence of primary tumor

Tis                    Carcinoma in situ

T1                    Tumor invades lamina propria or muscle layer

T1a                  Tumor invades lamina propria

T1b                  Tumor invades muscle layer

T2                    Tumor invades perimuscular connective tissue; no extension beyond serosa or into liver

T3                    Tumor perforates serosa (visceral perito-neum) or directly invades into one adjacent organ, or both (extension 2 cm or less into liver)

T4                    Tumor extends more than 2 cm into liver, and/or into two or more adjacent organs (stomach, duodenum, colon, pancreas,
                        omentum, extrahepatic bile ducts, any involvement of liver)

Regional Lymph Nodes (N)

NX                  Regional lymph nodes cannot be assessed

N0                   No regional lymph node metastasis

N1                   Metastasis in cystic duct, pericholedochal, and/or hilar lymph nodes (i.e. in the hepatoduodenal ligament)

N2                   Metastasis in peripancreatic (head only), periduodenal, periportal, celiac, and/or superior mesenteric lymph nodes

Note: The frequency of nodal involvement depends on the depth of invasion into the gallbladder wall by the primary tumor. To separate pN1 from pN2, the lymph nodes must be specifically identified. Peripancreatic nodes located along the body and tail of the pancreas are sites of distant metastasis. The hilar nodes include those along the inferior vena cava, hepatic artery, portal vein and hepatic pedicle.

Distant Metastasis (M)

MX                  Presence of distant metastasis cannot be assessed

M0                   No distant metastasis

M1                   Distant metastasis

Stage Groupings

Stage 0             Tis        N0       M0

Stage I T1        N0       M0

Stage II            T2        N0       M0

Stage III           T1        N1       M0

                        T2        N1       M0

                        T3        N0       M0

                        T3        N1       M0

Stage IVA        T4        N0       M0

                        T4        N1       M0

Stage IVB        Any T   N2       M0

                        Any T   Any N  M1

 

 

E.  Occult Carcinomas          back     Top     Main Page

Occasionally carcinoma is found in gallbladders removed by laparoscopic surgery. Not recognized clinically or by imaging techniques, tumor is discovered during pathologic evaluation of the resected specimen. In this setting, tumor spillage with seeding along the endoscopic tract or intra-abdominal dissemination may be a major complication of the procedure. If carcinoma in situ is found in such specimens, multiple sections should be examined to exclude invasive cancer.

 

To exclude occult carcinoma in gallbladders excised intact, at least three sections, one from the fundus, one from the body, and one from the neck should be submitted if no gross lesions are found.

 

F. Histologic Type           back     Top     Main Page

For consistency in reporting, the histologic classification proposed by the World Health Organization (WHO) is recommended.(4) However, this protocol does not preclude use of other systems of classification or histologic types. A modified WHO classification of gallbladder tumors follows:

 

WHO Classification of Gallbladder Carcinomas

•     Carcinoma in situ*

•     Adenocarcinoma**

•     Papillary carcinoma

•     Adenocarcinoma, intestinal type

•     Clear cell adenocarcinoma

•     Mucinous carcinoma***

•     Signet ring cell carcinoma+

•     Squamous cell carcinoma

•     Adenosquamous carcinoma

•     Small cell carcinoma (oat cell carcinoma)++

•     Undifferentiated carcinoma

 

*Because carcinoma in situ may be multifocal, cases of carcinoma in situ should be studied by multiple sections or by the “Swiss role” method in order to exclude invasive cancer in other areas of the gallbladder. Carcinoma in situ is often confused with the epithelial atypia of repair.(5)

 

**Many adenocarcinomas contain neuroendocrine cells. These tumors should not be considered neuroendocrine carcinomas.

 

***A mucocele may be mistaken for a mucinous carcinoma. Mucoceles often contain macrophages that have engulfed mucin (muciphages). Consequently these macrophages may resemble signet ring cells. Neoplastic signet ring cells are cytokeratin- and CEA-positive, whereas muciphages do not stain for these markers.

 

+All signet ring cell carcinomas are assigned Grade 3.

 

++Small cell carcinomas should be specifically reported since they may cause endocrine syndromes. In addition, small cell carcinomas are, by definition, high grade (grade 4), an adverse prognostic factor.(6)

 

G.  Histologic Grade              back     Top     Main Page

The following grading system, based on the extent of glandular formation in the tumor, is suggested.

 

Grade X     -     Grade cannot be assessed

Grade 1            -     Well differentiated (>95% of tumor composed of glands)

Grade 2            -     Moderately differentiated (50-95% of tumor composed of glands)

Grade 3            -     Poorly differentiated (5-49% of tumor composed of glands)

Grade 4            -     Undifferentiated (<5% of tumor composed of glands)

 

The definitions of the histologic grade are as follows:

Grade 1            -     Well differentiated adenocarcinomas are composed of more than 95% glands.

Grade 2            -     Carcinomas that are moderately differentiated are composed of 50%–95% glands.

Grade 3            -     Poorly differentiated carcinomas are composed of 5%–49% glands.

Grade 4            -     Undifferentiated carcinomas contain less than 5% glands and consist primarily of pleomorphic spindle and giant cells or small cells with
                        considerable nuclear atypia, small amounts of mucin, and no signficiant endocrine differentiation.

 

*Grade 4 carcinomas are classified as undifferentiated carcinomas (histologic type) by the WHO classification (see above).

 

Published data indicate that histologic grade is prognostically significant.(1)

 

H.  Blood/Lymphatic Vessel Invasion                     back     Top     Main Page

Published data indicate that blood vessel and/or lymphatic invasion has an adverse effect on outcome and should be specifically recorded.(1)

 

I.  Perineural Invasion            back     Top     Main Page

Perineural invasion by neoplastic cells is an adverse prognostic factor and should be reported. A diagnostic pitfall may occur in cases of adenomyomatous hyperplasia, since the ductal structures of adenomyomatous hyperplasia may invade perineural spaces.(7)

 

J.  Additional Pathologic Findings                             back     Top     Main Page

Other common lesions include chronic cholecystitis, dysplasia, carcinoma in situ, and various types of metaplasia such as squamous, pyloric gland, and intestinal. Occasionally changes consistent with inflammatory bowel disease are found in the gallbladder.

 

K.  Lymph Node Metastasis                      back     Top     Main Page

In general, carcinomas of the gallbladder spread from some focus in the hepatoduodenal ligament toward the nodes around the head of the pancreas. The cystic and pericholedochal nodes are the key stations for spread toward the peripancreatic nodes. Lymph flows through the pericholedochal nodes to these other regional nodes. Most often tumor initially metastasizes to the pericholedochal lymph nodes.

 

 

REFERENCES                        back     Top     Main Page

1.     Henson DE, Albores-Saavedra J, Corle D. Carcinoma of the gallbladder. histologic types, stage of disease, grade, and survival rates. Cancer. 1992;70:1493-1497.

2.     Sobin LH, Wittekind C, eds. TNM Classification of Malignant Tumours: International Union Against Cancer. 5th ed. New York, NY: Wiley , 1997.

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

4.     Albores-Saavedra J, Henson DE, Sobin LH. Histological Typing of Tumours of the Gallbladder and Extrahepatic Bile Ducts. WHO International Histological Classification of Tumours. Springer-Verlag, Berlin, 1991.

5.     Albores-Saavedra J, Henson DE. Gallbladder, In: Pathology of Incipient Neoplasia. Henson DE, Albores-Saavedra J, eds. WB Saunders, Philadelphia. 1993.

6.     Albores-Saavedra J, Henson, DE. Tumors of the Gallbladder and Extrahepatic Bile Ducts. Atlas of Tumor Pathology, 2nd Series, Fascicle 22. Washington, D.C. Armed Forces Institute of Pathology, 1986.

7.     Albores-Saavedra J, Henson DE. Adenomyomatous hyperplasia of the gallbladder with perineural invasion. Arch Pathol Lab Med. 1995;119:1173-1176.

 

 

BIBLIOGRAPHY

•      Albores-Saavedra J, Manrique JJ, Angeles-Angeles A, Henson DE. Carcinoma in situ of the gallbladder. A clinicopathologic study of 18 cases. Am J Surg Pathol. 1984;8:323-333.

•      Albores-Saavedra J, Alcantra-Vazquez A, Cruz-Ortiz H, Herrera-Goepfert R. The precursor lesions of invasive gallbladder carcinoma. Cancer. 1980;45:919-927.

•      Albores-Saavedra J, Soriano J, Larraza-Hernandez O, Aguirre J, Henson DE. Oat cell carcinoma of the gallbladder. Hum Pathol. 1984;15:639-646.

•      Bergdahl L. Gallbladder carcinoma first diagnosed at microscopic examination of gallbladders removed for presumed benign disease. Ann Surg. 1980;191:19-22.

•      Bivins BA, Meeker WR Jr, Griffen WO Jr. Importance of histologic classification of carcinoma of the gallbladder. Am Surg. 1975;41:121-124.

•      Bivins BA, Meeker WR Jr, Weiss DL, Griffen WO Jr. Carcinoma in situ of the gallbladder. South Med J. 1975;68:297-300.

•      Black WC. The morphogenesis of gall bladder carcinoma, In, Progress in Surgical Pathology, Vol II. Fenoglio CM, Wolff M. eds, Masson, NY, 1980.

•      Cavazzana AO, Fassina AS, Tollot M, Ninfo V. Small-cell carcinoma of gallbladder: An immunocytochemical and ultrastructural study. Pathol Res Pract. 1991;187:472-476.

•      Fahim RB, McDonald JR, Richards JC, Ferris DO. Carcinoma of the gallbladder: A study of its modes of spread. Ann  Surg. 1962;156:114-124.

•      Friedman RB, Anderson RE. Gilchrest KW, Carbone PP. Prognostic factors in invasive gallbladder carcinoma. J Surg Oncol. 1983;23:189-194.

•      Guo K-J, Yamaguchi K, Enjoji M. Undifferentiated carcinoma of the gallbladder: A clinicopathologic, histochemical, and immunohistochemical study of 21 patients with a poor prognosis. Cancer. 1988;61:1872-1879.

•      Higgs WR, Mocega EE, Jordan PH. Malignant mixed tumor of the gallbladder. Cancer. 1973;32:471-475.

•      Johnstone AK, Zuch RH, Anders KH. Oat cell carcinoma of the gallbladder. A rare and highly lethal neoplasm. Arch Pathol Lab Med. 1993;117:1009-1012.

•      Nevin JE, Moran TJ, Kay S, King R. Carcinoma of the gallbladder. Staging, treatment, and prognosis. Cancer. 1976;37:141-148.

•      Ouchi K, Owada Y, Matsuno S, Sato T. Prognostic factors in the surgical treatment of gallbladder carcinoma. Surgery. 1987;101:731-737.

•      Shirai Y, Tsukada K, Ohtani T, Watanabe H, Hatakeyama K. Hepatic metastases from carcinoma of the gallbladder. Cancer. 1995;75:2063-2068.

•      Shirai Y, Yoshida K, Tsukada K, Ohtani T, Muto T. Identification of the regional lymphatic system of the gallbladder by vital staining. Br J Surg. 1992;79:659-662.

•      Wanebo HJ, Castle WN, Fechner RE. Is carcinoma of the gallbladder a curable lesion? Ann Surg. 1982;195:624-630.

•      Yamaguchi K, Tsuneyoshi M. Subclinical gallbladder carcinoma. Am J Surg. 1992;163:382-386.

 

 

 

 

 

 

Authors

Donald E. Henson, MD; Jorge Albores-Saavedra, MD;

Carolyn C. Compton, MD, PhD

 

©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.

 

Contributors:                      back     Top     Main Page

        CAP Cancer Committee