Kidney

Protocol applies to all carcinomas of renal tubular origin.

It excludes Wilm’s tumors and tumors of urothelial origin.

Procedures

• Cytology

• Incisional Biopsy

• Partial Nephrectomy

• Radical Nephrectomy

 

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)

                  d.   Gender

            2.   Responsible physician(s)

            3.   Date of procedure

            4.   Other clinical information

                  a.   Relevant history (e.g. previous diagnoses and treatment, family history of renal tumors)

                  b.   Relevant findings (e.g. imaging studies)

                  c.   Clinical diagnosis

                  d.   Procedure (e.g. FNA)

                  e.   Anatomic site(s) of specimen (e.g. kidney, metastatic site)

 

      B.   Macroscopic Examination

            1.   Specimen

                  a.   Unfixed/fixed (specify fixative)

                  b.   Number of slides received

                  c.   Quantity and appearance of fluid specimen

                  d.   Other materials received

                  e.   Results of intraprocedural consultation

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

            3.   Special studies (specify) (e.g. histochem-istry, immunohistochemistry, cytogenetic analysis)

 

      C.  Microscopic Evaluation

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

            2.   Tumor, if present

                  a.   Histologic type if possible (Note A)

                  b.   Other features (e.g. grade/necrosis)

            3.   Other pathologic findings

            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. Incisional Biopsy (needle or wedge)                  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. previous diagnoses and treatment, family history of renal tumors)

                  b.   Relevant findings (e.g. imaging studies)

                  c.   Clinical diagnosis

                  d.   Procedure (e.g. needle biopsy)

                  e.   Anatomic site(s) of specimen (e.g. left kidney)

 

      B.   Macroscopic Examination

            1.   Specimen

                  a.   Unfixed/fixed (specify fixative)

                  b.   Number of pieces

                  c.   Dimensions

                  d.   Descriptive features

                  e.   Orientation (if designated by surgeon)

                  f.    Results of intraoperative consultation

            2.   Tissue submitted for microscopic evaluation, as appropriate

                  a.   Entire specimen

                  b.   Selected sample

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

            3.   Special studies (specify) (e.g. histochem-istry, immunohistochemistry, morphometry, DNA analysis [specify type], cytogenetic analysis)

      C.  Microscopic Evaluation

            1.   Tumor

                  a.   Histologic type (if possible) (Note A)

                  b.   Histologic grade (Note B)

                  c.   Blood/lymphatic vessel invasion (if possible to determine)

                  d.   Extracapsular extension (if possible to determine)

            2.   Additional pathologic findings, if present

            3.   Result/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

III. Partial Nephrectomy               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. previous diagnoses and treatment, family history of renal tumors)

                  b.   Relevant findings (e.g. imaging studies)

                  c.   Clinical diagnosis

                  d.   Procedure (Note C)

                  e.   Operative findings

                  f.    Anatomic site(s) of specimen (e.g. left partial kidney, upper pole)

 

      B.   Macroscopic Examination

            1.   Specimen

                  a.   Organs/tissues included

                  b.   Unfixed/fixed (specify fixative)

                  c.   Type of specimen (Note C)

                  d.   Kidney size — three dimensions

                  e.   Weight (kidney and tumor(s) with perirenal fat removed)

                  f.    Orientation (if indicated by surgeon)

                  g.   Weight of adrenal gland, if present

                  h.   Presence or absence of:

                        (1)  renal capsule

                        (2)  perirenal fat

                  i.    Other organs/tissue(s) (weigh or measure, as appropriate)

                  j.    Results of intraoperative consultation

            2.   Tumor(s)

                  a.   Number

                  b.   Location

                  c.   Size(s) (Note D)

                  d.   Descriptive characteristics (e.g. solid/cystic, color, consistency,  necrosis)

                  e.   Extent of invasion (Note D)

                  f.    Lymph/vascular vessel invasion

            3.   Margins

                  a.   Renal capsule

                  b.   Renal vessels

                  c.   Ureter

                  d.   Cut surface of kidney, if heminephrectomy

            4.   Regional lymph nodes (Notes D and E)

                  a.   Number

                  b.   Location (if possible) (Note E)

            5.   Tissues submitted for microscopic evaluation

                  a.   Tumor (one section for each cm of tumor diameter and/or different gross appearances)

                  b.   Non-neoplastic kidney (one section minimum)

                  c.   Sections to document tumor extent

                        (1)  calices, renal pelvis

                        (2)  perirenal tissue (including hilus)

                        (3)  blood vessels

                  d.   All lymph nodes

                  e.   Margins (all)

                  f.    Adrenal gland (one section minimum)

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

                  h.   Other tissue(s) (as appropriate)

            6.   Special studies (specify) (e.g. histochemistry, immunohistochemistry, morphometry, DNA analysis [specify   type], cytogenetic analysis)

 

      C.  Microscopic Evaluation

            1.   Tumor

                  a.   Histologic type (Note A)

                  b.   Histologic grade (Note B)

                  c.   Extent of invasion (Note D)

                  d.   Blood/lymphatic vessel invasion (Note D)

            2.   Margins

                  a.   Renal capsule

                  b.   Renal vessels

                  c.   Ureter

                  d.   Cut surface of kidney, if heminephrectomy

            3.   Regional lymph nodes

                  a.   Number

                  b.   Number with metastasis* (Note D) (specify location if possible)

                        *Measure largest involved node

            4.   Metastasis to other organ(s) or structure(s) (specify site)

            5.   Additional pathologic findings, if present

            6.   Other tissue(s)/organ(s) (e.g. adrenal)

            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

 

IV. Radical Nephrectomy            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. previous diagnoses and treatment, family history of renal tumors)

                  b.   Relevant findings (e.g. imaging studies)

                  c.   Clinical diagnosis

                  d.   Procedure (e.g. radical nephrectomy, with adrenalectomy, vena cava thrombectomy and lympadenectomy) (Note F)

                  e.   Operative findings

                  f.    Anatomic site(s) of specimen (e.g. left kidney)

 

      B.   Macroscopic Examination

            1.   Specimen

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

                  b.   Unfixed/fixed (specify fixative)

                  c.   Description of perirenal fat/Gerota’s fascia

                  d.   Weight of adrenal gland, if present

                  e.   Kidney size (three dimensions)

                  f.    Weight (kidney and tumor(s) with perirenal fat removed)

                  g.   Length of ureter

                  h.   Other submitted tissues and weigh or measure as appropriate (e.g. venous tumor thrombus, specimens from other organs, etc.)

                  i.    Results of intraoperative consultation

            2.   Tumor(s)

                  a.   Number

                  b.   Location

                  c.   Size(s) (Note D)

                  d.   Descriptive characteristics (e.g. solid/cystic, color, consistency, necrosis)

                  e.   Extent of invasion (Note D)

                  f.    Hilar invasion

                  g.   Renal vein invasion

            3.   Margins

                  a.   Gerota’s fascia

                  b.   Renal vessels

                  c.   Ureter

            4.   Regional lymph nodes (Notes D and E)

                  a.   Number

                  b.   Location (if possible)

            5.   Separately submitted tissues (specify)

            6.   Tissue submitted for microscopic evaluation

                  a.   Tumor (one section for each cm of tumor diameter and/or different gross appearances)

                  b.   Uninvolved kidney (one section minimum)

                  c.   Sections to document tumor extent

                        (1)  calices, renal pelvis

                        (2)  ureter

                        (3)  perirenal tissues (including hilus and Gerota’s fascia)

                        (4)  renal vessels (includes separately submitted tumor thrombus)

                  d.   All lymph nodes

                  e.   Margins (as appropriate)

                  f.    Adrenal gland (one section minimum)

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

                  h.   Other tissue(s), as appropriate

            7.   Special studies (specify)

 

      C.  MicroscopIc Evaluation

            1.   Tumor

                  a.   Histologic type (Note A)

                  b.   Histologic grade (Note B)

                  c.   Extent of invasion (Note D)

                  d.   Blood/lymphatic vessel invasion

            2.   Margins

                  a.   Gerota’s fascia

                  b.   Renal vessels

                  c.   Ureter

                  d.   Other(s) (as appropriate)

            3.   Regional lymph nodes

                  a.   Number (Note D)

                  b.   Number with metastasis* (specify location if possible) (Note D)

                        *Measure largest involved node

            4.   Metastasis to other organs(s) or structure(s) (specify site)

            5.   Additional pathologic findings, if present

            6.   Other tissue(s)/organs

            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.  Histologic Type                back     Top     Main Page

The histopathologic classification most recently published by the American Joint Committee on Cancer (AJCC) and the International Union Against Cancer (UICC) is recommended and shown below.(1-2) However, the protocol does not preclude the use of other published classifications(3-10) which appear in the Atlas of Tumor Pathology, 3rd series, Fascicle 11, Tumors of the Kidney, Bladder and Related Urinary Structures is also shown below.(3)

 

AJCC/UICC Histologic Classification of Renal Carcinoma(1-2)

•     Conventional (clear cell) renal carcinoma

•     Papillary renal carcinoma

•     Chromophobe renal carcinoma

•     Collecting duct carcinoma

•     Renal cell carcinoma, unclassified

 

AFIP Histologic Classification of Renal Cell Carcinoma(3)

•     Clear cell (hypernephroid) renal cell carcinoma

•     Granular renal cell carcinoma*

•     Papillary renal cell carcinoma

•     Chromophobe renal cell carcinoma

•     Collecting duct type renal cell carcinoma

•     Sarcomatoid renal cell carcinoma*

•     Mixed type renal cell carcinoma

•     Renal cell carcinoma, undifferentiated

 

* These histologic types of renal cell carcinoma are not included in the AJCC/UICC classification shown above because it is argued that they may not represent unique forms of differentiation. Abundant granular cytoplasm may occur in any of the following tumor types: oncocytoma, chromophobe renal cell carcinoma, papillary renal cell carcinoma, collecting duct carcinoma and epithelioid angiomyolipoma. Sarcomatoid morphology may be manifested by any renal cell carcinoma (conventional, papillary, chromophobe, or collecting duct subtypes) as well as urethelial carcinoma of the renal pelvis and may represent a progression in tumor grade.

 

B.   Histologic Grade           back     Top     Main Page

The grading scheme for renal cell carcinoma of Fuhrman, et al. is recommended and shown below.(11)  However, the protocol does not preclude the use of other grading schemes.(12-16) The system of grading should be specified in the report.

 

 

Grade X           Cannot be assessed

Grade 1            Nuclei round, uniform, approximately 10 µm in diameter; nucleoli inconspicuous or absent

Grade 2            Nuclei slightly irregular, approximately 15 µm in diameter; nucleoli evident

Grade 3            Nuclei very irregular, approximately 20 µm in diameter; nucleoli large and prominent

Grade 4            Nuclei bizarre and multilobated, 20 µm or greater in diameter, nucleoli prominent, chromatin clumped.

 

C.  Operative Procedures         back     Top     Main Page

A partial nephrectomy may vary from a simple enucleation of the tumor to a partial nephrectomy including variable portions of the calyceal or renal pelvic collecting system. The perirenal fat immediately overlying the resected portion of kidney but not to the level of Gerota’s fascia is usually included.

 

D. TNM and Stage Groupings              back     Top     Main Page

 

The TNM Staging System for renal cell of the AJCC/UICC is recommended and shown below. (17)

 

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.

 

Residual Tumor 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).

 

Residual Tumor 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. 

 

Primary Tumor (T)

TX       Primary tumor cannot be assessed

T0        No evidence of primary tumor

T1        Tumor 7.0 cm or less in greatest dimension limited to the kidney

T2        Tumor more than 7.0 cm in greatest dimension limited to the kidney

T3        Tumor extends into major veins or invades the adrenal gland or perinephric tissues but not beyond Gerota’s fascia

      T3a            Tumor invades the adrenal gland* or perinephric tissues but not beyond Gerota’s fascia

      T3b            Tumor grossly extends into the renal vein(s) or vena cava below the diaphragm

      T3c            Tumor grossly extends into the vena cava above the diaphragm

T4        Tumor invades beyond Gerota’s fascia.

 

*Direct invasion of the adrenal gland, which is categorized as local extension, must be differentiated from metastatic tumor in the adrenal which is categorized M1 (see below for Distant Metastasis).

 

Regional Lymph Nodes (N) † (see Note E below)

NX            Regional lymph nodes cannot be assessed

N0       No regional lymph node metastasis

N1       Metastasis in a single lymph node

N2       Metastasis in more than one regional lymph node

 

 †Note: Laterality does not affect the N classification.

 

Distant Metastasis (M)

MX            Distant metastasis cannot be assessed

M0       No distant metastasis

M1       Distant metastasis

 

Stage Groupings

Stage I       T1  N0 M0

Stage II      T2  N0 M0

Stage III     T1  N1 M0

                  T2  N1 M0

                  T3  N0, N1      M0

Stage IV     T4  N0, N1      M0

                  Any T   N2 M0

                  Any T   Any N  M1

E.   Lymph Nodes        back     Top     Main Page

Regional lymphadenectomy is not generally performed even with a radical nephrectomy. A few lymph nodes may be found in a nephrectomy specimen in the renal hilus around the major renal vessels. Other regional lymph nodes, paracaval, para-aortic and retroperitoneal, may be submitted separately.

 

F.   Radical Nephrectomy         back     Top     Main Page

A standard radical nephrectomy specimen consists of the entire kidney, including the calyces, pelvis and a variable length of ureter. The adrenal gland is usually removed en bloc with the kidney. The entire perirenal fatty tissue is removed to the level of Gerota’s fascia, a membranous structure, similar to the consistency of the renal capsule, which encases the kidney and perirenal fat. Variable lengths of the major renal vessels, at the hilus are submitted.  Some lymph nodes may be present in the renal hilus.

 

REFERENCES            back     Top     Main Page

1.     Störkel S, Eble JN, Adlakha K, et al. Classification of renal cell carcinoma. Workgroup No. 1. Cancer. 1997;80:987-989.

2.     Amtrup F, Hausen JB, Thybo E. Prognosis in renal cell carcinoma evaluated from histological criteria. Scand J Urol Nephrol. 1974;8:198-202.

3.     Murphy WM, Beckwith JB, Farrow GM. Tumors of the adult kidney. In: Tumors of the Kidney, Bladder and Related Structure.  Atlas of Tumor Pathology. 3rd series. Fascicle 11. Washington, DC: Armed Forces Institute of Pathology; 1994: 98-124.

4.     Angervall L, Carlström E, Wahlqvist L, Ahren C. Effects of clinical and morphologic variables on spread of renal cell carcinoma in an operative series. Scand J Urol Nephrol. 1969;3:134-140.

5.     Bennington JL. Tumors of the kidney. In: Javadpour N, Barsky SH, eds. Surgical Pathology of Urologic Diseases. Baltimore, MD: Williams and Wilkins; 1987:120-122.

6.     Fleming S. The impact of genetics on the classification of renal carcinoma. Histopathology. 1993;22:89-92.

7.     Kovacs G. Molecular differential pathology of renal cell tumours. Histopathology. 1993;22:1-8.

8.     Mathisen W, Muri O, Myhre E. Pathology and prognosis in renal tumors. Acta Chir Scand. 1965;130:303-313.

9.     Petkovic SD. An anatomical classification of renal tumors in the adult as a basis for prognosis. J Urol. 1959;81:618-623.

10.   Thoenes W, Storkel S, Rumpelt HJ. Histopathology and classification of renal cell tumors (adenomas, oncocytomas and carcinomas). Pathol Res Pract. 1989;181:125-143.

11.   Fuhrman SA, Lasky LC, Limas C. Prognostic significance of morphologic parameters in renal cell carcinoma. Am J Surg Pathol. 1982;6:655-663.

12.   Arner O, Blanck C, van Schreeb T. Renal adenocarcinoma: Morphology grading of malignancy, prognosis. A study of 197 cases. Acta Chir Scand. 1965;346 (Suppl):1-51.

13.   Hermanek P, Sigel A, Chlepas S. Histological grading of renal cell carcinoma. Eur Urol. 1976; 2:189-191.

14.   Siminovitch JM, Montie JE, Straffon RA. Prognostic indicators in renal adenocarcinoma. J Urol. 1983;130:20-23.

15.   Skinner DG, Colvin RB, Vermillion DC, Pfester RC, Leadbetter WF. Diagnosis and management of renal cell carcinoma:  A clinical and pathologic study of 309 cases. Cancer. 1971; 28:1165-1177.

16.   Syrjänen K, Hjelt L. Grading of human renal adenocarcinoma. Scand J Urol Nephrol. 1978; 12:49-55.

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

 

 

Authors:

George Farrow, MD and Mahul B.  Amin, 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:          back     Top     Main Page
CAP Cancer Committee