|Year : 2021 | Volume
| Issue : 4 | Page : 493-500
Gross reporting of adult kidney tumor specimens: A comprehensive evidence-based review
Divya Midha1, Santosh Menon2, S Josephine3, Ramani M Kumar4, Seema Kaushal5, Sanjay A Pai6, Asawari Ambekar7, Vishal Rao8, MR Bindhu9, Sachin Patil10, Rakhi Jagdale10, Shailesh Soni11, Bijal Kulkarni12, Sangeeta Desai2, Sandhya Sundaram3
1 Department of Pathology, Tata Medical Center, Kolkata, West Bengal, India
2 Department of Pathology, Tata Memorial Hospital, Homi Bhabha National Institute, Mumbai, Maharashtra, India
3 Department of Pathology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India
4 Department of Pathology, Christian Medical College, Vellore, Tamil Nadu, India
5 Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
6 Department of Pathology, Columbia Asia Referral Hospital, Bangalore, Karnataka, India
7 Department of Pathology, Apollo Hospitals, Navi Mumbai, Maharashtra, India
8 Department of Pathology, Basavatarakam Indo American Cancer Hospital and Research Institute, Hyderabad, Telangana, India
9 Department of Pathology, Amrita Institute of Medical Sciences, Kochi, Kerala, India
10 Department of Pathology, Shri Siddhivinayak Ganapati Cancer Hospital, Miraj, Maharashtra, India
11 Department of Pathology, Muljibhai Patel Urological Hospital, Nadiad, Gujarat, India
12 Department of Pathology, Kokilaben Dhirubhai Ambani Hospital and Research Centre, Mumbai, Maharashtra, India
|Date of Submission||31-Mar-2021|
|Date of Decision||04-Apr-2021|
|Date of Acceptance||22-Sep-2021|
|Date of Web Publication||31-Dec-2021|
Department of Pathology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu
Source of Support: None, Conflict of Interest: None
Renal tumors comprise a wide spectrum of benign and malignant tumors. The important prognostic factors in renal cell carcinoma include pathological stage, tumor grade, morphological type, sarcomatoid/rhabdoid differentiation, and tumor necrosis. Therefore, the pathologist needs to be fully aware of how to gross nephrectomy specimens to be able to accurately provide the above prognostic information while reporting adult kidney tumors. With the advent of nephron-sparing surgeries, due diligence should be exercised to assess and sample the parenchymal surgical margin. This article discusses the approach to grossing nephrectomy specimens, elaborates the significance of every step, and also sheds light on the importance of clinical and radiological information in providing a holistic approach to the diagnosis and staging of adult renal tumors.
Keywords: Grossing, margin assessment, renal cell carcinoma, stagingKey Message While grossing adult renal tumors, pathologists play a very important role in recognising key staging parameters as this can affect patient prognosis. A key message is to be cautious while grossing larger tumours and those with any deviation from a spherical shape (especially finger-like protrusions) for presence of vascular or renal sinus invasion, which results in a pT3a stage category
|How to cite this article:|
Midha D, Menon S, Josephine S, Kumar RM, Kaushal S, Pai SA, Ambekar A, Rao V, Bindhu M R, Patil S, Jagdale R, Soni S, Kulkarni B, Desai S, Sundaram S. Gross reporting of adult kidney tumor specimens: A comprehensive evidence-based review. Indian J Cancer 2021;58:493-500
|How to cite this URL:|
Midha D, Menon S, Josephine S, Kumar RM, Kaushal S, Pai SA, Ambekar A, Rao V, Bindhu M R, Patil S, Jagdale R, Soni S, Kulkarni B, Desai S, Sundaram S. Gross reporting of adult kidney tumor specimens: A comprehensive evidence-based review. Indian J Cancer [serial online] 2021 [cited 2022 Jan 19];58:493-500. Available from: https://www.indianjcancer.com/text.asp?2021/58/4/493/334637
| » Introduction|| |
Renal tumors include a heterogeneous and diverse spectrum of neoplasms. Recent advances have significantly improved our understanding of the morphological, immunohistochemical, molecular, epidemiological, and clinical characteristics of renal tumors, which has resulted in the Vancouver classification of renal neoplasia and the 2016 World Health Organization (WHO) classification of renal cell tumors. New and emerging/provisional renal entities,, are being added to this complex and evolving list, stimulating new studies and discussions for targeted therapy.
Radical nephrectomies are commonly performed for tumors that are large and confined to the kidney. Partial nephrectomies are becoming more common for resection of small renal masses or if the contralateral kidney is absent or nonfunctioning. Apart from offering comparable oncological and functional efficacy, partial nephrectomy also comes with the additional advantage of nephron-sparing, decreasing the risk of chronic renal insufficiency. Accurate pathological evaluation of renal neoplasms is essential for diagnosis, subtyping, staging, prognostication, and determining further treatment protocols.
Patient demographics, particularly age, are vital to diagnose renal tumors. Renal cell carcinoma (RCC) is the ninth most common malignancy worldwide and even more common in developed countries (up to 6% of all cancers), with a peak of incidence occurring between 60 and 70 years of age, with a 3:2 male:female ratio. Renal tumors account for about 7% of all tumors in children before the age of 15 years with Wilms tumor or nephroblastoma being the most common primary renal neoplasm in children. MiT family translocation RCC's should also be considered particularly in children and young adults presenting with RCC.
The identification of risk factors associated with renal tumors, as well as family history of renal tumors and other hereditary diseases (von Hippel–Lindau disease, succinate dehydrogenase–deficient RCC, fumarate hydratase–deficient RCC, Birt–Hogg–Dubé syndrome, hereditary papillary RCC (pRCC), autosomal dominant polycystic kidney disease), is significant for diagnosis, prognosis, surveillance, management, and genetic counseling.,,
Clinical findings act as an adjunct to pathological findings in the precise diagnosis of renal tumors. Information about any pre-operative therapy (targeted therapy, immunotherapy, tumor ablation, or embolization) is of paramount importance. Prior tumor embolization and prior therapy nullify the prognostic significance of any tumor necrosis observed histologically.
Radiological information pertaining to the extent of disease and the presence of metastasis is vital for staging and may also help in subtyping of tumors and exclusion of mimickers of RCC.
Imaging in renal masses
Detection of incidental renal masses has grown exponentially due to the widespread use of ultrasonography (USG), computed tomography (CT), and magnetic resonance imaging (MRI) for a variety of indications.
USG is generally the first line for patients with suspected renal lesions given its lower cost, wide availability, and lack of ionizing radiation. Characterization of cystic renal lesions is most frequently done on USG, although the appearance of complex cystic masses and solid lesions may overlap.
CT has higher sensitivity for the detection of renal lesions, with a diagnostic accuracy of 95%. Various morphological features of renal masses can be evaluated by CT, including their internal content (calcifications, fat, areas of necrosis, septations, mural nodules, and the cystic component) and enhancement. It is the most commonly used method to evaluate indeterminate renal masses and is also considered the method of choice to stage RCC.
Compared with CT, MRI has better contrast resolution and also does not expose patients to ionizing radiation. When the CT findings are inconclusive, the patient can be better evaluated by MRI, as can pediatric patients, pregnant patients, and patients for whom the use of contrast media is contraindicated.
The use of (18)F-fluorodeoxyglucose positron emission tomography (PET)/CT is not recommended as a primary diagnostic imaging modality for RCC due to its low sensitivity and specificity for detection and characterization of the same.
The first step in the workup of incidentally found renal masses is to differentiate benign cysts from solid masses. Solid malignant masses most frequently encountered in the clinical practice are RCC, urothelial carcinoma, lymphoma, and metastasis, whereas the most frequently encountered benign solid renal masses are angiomyolipoma (AML) and oncocytoma.
AMLs are benign neoplasms consisting of aberrant blood vessels, smooth muscle, and mature adipose tissue, representing 2% to 6% of all resected tumors in surgical series. The detection of fatty tissue (i.e. adipocytes) by CT or MRI is regarded as the most specific feature of this diagnosis radiologically, although many pathologically proven AMLs do not show fatty tissue on imaging, posing a diagnostic challenge to radiologists.
Oncocytomas are relatively uncommon cortical tumors (approximately 7% of renal masses in surgical series), and on imaging, intratumoral hemorrhage and central scars are present in 20% and 33% of all oncocytomas, respectively, and multifocality may occur in 13% of the patients.
Attempts to histologically subtype RCCs on USG have been inconsistent so far. On CT, differentiation of RCC subtypes generally relies on analyses of postcontrast time-attenuation curves and lesion homogeneity. Postcontrast enhancement of clear cell RCC (ccRCC) is significantly higher than that observed for pRCC and chromophobe RCC (chRCC), while heterogeneity is also more frequently seen in ccRCC. Tumor histological grade has prognostic implications and therefore may affect patient management. However, the accuracy of prediction of tumor grade by imaging methods is limited. On MRI, renal vein thrombosis and retroperitoneal collaterals were predictive of high-grade ccRCC, whereas peripheral location and homogeneous enhancement were associated with low-grade pRCC.
Although mostly considered experimental, nuclear imaging modalities show promising results in differentiating ccRCC and oncocytomas.
Prerequisites for grossing
Prior to the handling of the specimen by the pathologist, the role of the urologist in the preservation of anatomical structures along with clinical and surgical information is vital to diagnosis. The specimen should be sent intact with surrounding perirenal fat. Lymphadenectomy specimens should ideally be sent in a separate container.
Along with specimen laterality and type of surgical procedure, the type of surgical approach (open, robotic, or laparoscopic) should be mentioned for assessment of margin status. This becomes challenging in laparoscopic procedures with morcellation. Inclusion of ipsilateral adrenal gland and histopathology of any prior excised renal tissue should be mentioned.
| » Types of specimens and fixation|| |
Radical nephrectomy and simple nephrectomy
Radical nephrectomy includes the kidney and perinephric fat with surrounding Gerota's fascia, a length of the ureter, and may or may not include the adrenal gland.
Simple nephrectomy specimens consist of a kidney with a variable amount of attached perinephric fat and a length of ureter.
Adequate fixation of the sliced specimen in 10% neutral-buffered formalin is essential for good morphological preservation, proper assessment, and sampling of key areas such as the interface of the tumor with its surroundings. Suboptimal fixation also affects the results of downstream investigations.
The capsule should not be stripped at any point. The surface should be examined for any fissures, rupture, or suspicious-looking areas. Prior inking of the specimen including inking any potential/suspected areas of margin involvement is recommended.
The most common plane of initial incision is the midline longitudinal incision along the long axis of the kidney, from the lateral or medial aspect, dividing the kidney into broadly symmetrical anterior and posterior halves. This maximizes the visualization of the tumor/renal sinus interface, which is a key area of macroscopic assessment. Further incisions (usually taken parallel to the initial incision, anteriorly and posteriorly) may be necessary to adequately expose the tumor. The sectioning should be done with perinephric tissues attached so that small foci of capsular penetration are not missed. Large tumors require at least 24 hours of fixation after initial sectioning prior to detailed dissection and sampling.
Fresh or frozen samples of the tumor, if required for research purposes, call for snap freezing of the tissue sections as optimum preservation of RNA (ribonucleic acid)/DNA (deoxyribonucleic acid) is necessary for any molecular studies. Coordination among the surgeon, pathologist, and the laboratory/biorepository helps maintain specimen integrity. In centers, where a delay in transportation time of samples is anticipated, the departments should agree on a method of fixation and transportation that aids to preserve the tissue in the best possible way.
A partial nephrectomy specimen consists of the tumor that has been enucleated or is excised with a variable amount of surrounding renal tissue, with or without attached perinephric fat. Part of the pelvicalyceal system may also be included. In these specimens, the parenchymal (intrarenal) surgical margin should be inked first, and optionally the external surface. Incisions perpendicular to the plane of the parenchymal margin help assess the distance of the tumor from this margin.
Lymphadenectomy specimen and adrenal gland
Lymphadenectomy specimens do not require special processing and are generally fixed en bloc in formalin, but large lymph node masses may require an incision to facilitate fixation. If the adrenal gland is included, parallel sections must be taken, while looking for any grossly visible pathological change or involvement by the tumor.
| » Grossing the specimen – How and why we do it?|| |
Simple and radical nephrectomy
Handling the specimens is similar for simple and radical nephrectomy.
- Specimen orientation:
The specimen should first be oriented using the position of the adrenal gland, ureter, and hilar structures. The adrenal gland lies superior to the upper pole of the kidney. The ureter extends inferiorly from the hilum along the medial border. At the hilum, the renal vein normally lies anterior to the renal artery (although there are frequent anatomical variations), and the renal pelvis is posterior to both.
- The entire specimen should be measured in three dimensions.
Due to the variation in the amount of the attached perinephric fat, the kidney should be measured excluding the perinephric fat. However, this should be done without stripping the fat, to be able to properly assess perinephric fat invasion.
- Macroscopic examination of external structures:
This is vital for TNM (tumor, node, and metastases) staging of the tumor and for appropriate block selection. This involves the renal artery, vein, ureter, inferior vena cava (IVC, if included in the specimen), hilar fat, and adrenal gland.
- Renal artery should be identified and the margin sampled transversely.
- Two options for sampling the renal vein margin include amputating the distal-most vein wall cross-section, including the tumor, or trimming the vein wall separately from the tumor with scissors (if the wall is freely mobile). Either of these should yield an adequate full cross-section of the distal-most vein wall for evaluation. The 2012 International Society of Urologic Pathology Consensus defines a renal vein margin as positive, only if there is an adherent tumor at the actual margin [Figure 1].
- Occasionally, RCCs can also spread retrogradely within vein branches, a phenomenon that appears to be exclusively associated with occlusion of the main renal vein by tumor, and that is found in approximately 5% - 8% of RCCs.
|Figure 1: Clear-cell renal cell carcinoma showing invasion of renal vein with tumor cells adherent to the wall. 200×, hematoxylin and eosin stain|
Click here to view
This retrograde venous invasion is defined as rounded or elongated nodules of tumor separated from the primary tumor by uninvolved renal parenchyma in locations that conforms to the normal venous outflow of the kidney. Awareness of this phenomenon, meticulous gross examination of renal sinus fat, and knowledge of venous anatomy are critical to the assessment of renal cancer specimens. The retrograde venous invasion should be considered carefully before considering multifocal ccRCC. Histological sections should be taken from tumor satellites or outpouchings that deviate from the usual spherical shape of RCC as these could represent retrograde venous invasion. This would upstage the tumor from pT1/pT2 to pT3a.
- The length of the ureter included and its appearance, whether of normal caliber or not, are recorded. Careful opening of the ureter (after taking the transverse section of the surgical margin) enables the detection of incidental focal lesions.
- If IVC involvement is suspected, a part of it is included in the nephrectomy specimen, where it is considered the main vascular surgical margin, or an IVC thrombus is sent separately, in which case it should be examined for adherent vessel wall. Such grossly visible invasion amounts to stage pT3b or pT3c staging, based on the extent of intravascular tumor thrombus.,
- The hilar fat is examined grossly for palpable lymph nodes. Lymph nodes are found in the hilar region in less than 10% of nephrectomy specimens. Studies have shown that most of the grossly palpable lymph nodes are reported as positive, whereas microscopically detected lymph nodes have a higher probability of being benign suggesting that random microscopic assessment of hilar fat for microscopic lymph nodes may be unnecessary. The American Joint Committee on Cancer (AJCC), eighth edition continues to include only the pN1 for the involvement of one or more regional lymph nodes. There is some evidence that extranodal extension of the tumor may be more important than the number of lymph nodes involved.
- Gross examination of the adrenal gland includes measurement of its dimensions and assessment for direct extension of tumor or the presence of discrete nodules signifying metastasis, both of which are part of TNM staging (pT4 and pM1, respectively). Hence, sampling of the adrenal gland should be done adequately.
- Assessment and sampling of the renal tumor:
A digital photograph of the gross specimen provides a visual record of tumor location, appearance, extent and is useful for annotating the sites from where blocks have been taken [Figure 2].
|Figure 2: Gross specimen of renal cell carcinoma with marked areas of representative bits to be taken|
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- The location of the renal tumor is noted with respect to the poles of the kidney as well as cortical/medullary involvement. While adenomas and oncocytomas are known to involve the renal cortex, collecting duct carcinomas/medullary carcinomas and primary urothelial carcinoma of the renal pelvis may occur or involve the medullary region primarily.
- Grossly, ccRCCs characteristically contain solid yellow areas with variable amounts of cystic change, hemorrhage, and necrosis. pRCCs are grossly solid, with or without cystic change or encapsulation, and are often gray or brown in color with a soft friable cut surface showing frequent necrosis and hemorrhage [Figure 3]. chRCCs are characteristically tan in color, similar to the benign renal oncocytoma that is the main differential diagnosis.
- The tumor is sampled for accurate tumor typing and grading on histology both of which influence tumor prognosis.
|Figure 3: Gross picture of a typical papillary carcinoma with pseudocapsule and friable tumor|
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Many large multicenter studies have shown that tumor type has prognostic significance. ccRCC has a worse prognosis than pRCC or chRCCs, when matched for stage and is more likely to present at an advanced stage or with existing metastasis. Tumor type also has utility in the selection of patients for adjuvant therapy, further underlining the importance of accurate tumor typing.
The grading of RCC is based on nucleolar prominence/eosinophilia for Grades 1–3, whereas Grade 4 requires nuclear anaplasia (including tumor giant cells, sarcomatoid differentiation, and/or rhabdoid morphology). This grading has been designated as WHO/ISUP (International Society of Urologic Pathologists) grading system in the fourth edition of the WHO classification tumors of the urinary system and male genital organs (2016) and has been validated for both ccRCC [Figure 4] and pRCC for its prognostic utility and has not been validated for other tumor types. The tumor grade is assigned on microscopy according to the cells with the highest grade present, rather than the most predominant.
|Figure 4: Clear-cell renal cell carcinoma – high-power image showing compact arrangement of tumor cells with distinct cell borders, abundant clear cytoplasm, and Grade 2 nuclei. 200v, hematoxylin and eosin stain|
Click here to view
- The maximum dimension of the tumor including its extension into the perinephric fat is recorded (in mm). One should not measure tumor invading into renal/caval vein. Tumor size is an important component of the TNM staging with cutoffs for prognostic significance (T1a 40 mm, T1b 70 mm, T2a 100mm). Bigger tumors (>70 mm) are associated with extrarenal spread into the renal sinus and renal vein and are found to influence clinical outcomes and mortality.
- Apart from following the basic rule of “one block per centimeter,” all solid and cystic areas with differing gross appearances should be sampled due to the heterogeneous nature of these tumors and to facilitate tumor grading and staging. Fleshy areas should be sampled as this could represent foci of sarcomatoid/rhabdoid differentiation [Figure 5]. Grossly necrotic areas should also be sampled (one to two sections) due to the frequent presence of high-grade areas adjacent to the areas of necrosis. Tumor necrosis is an important prognostic factor, and both macroscopic and microscopic (coagulative) necrosis should be recorded. The prognostic accuracy of the extent of tumor necrosis is unclear; however, this should be recorded as a percentage.
- If multiple tumors are present, the maximum dimension of the largest five are measured and sampled, including any smaller ones that differ in gross appearance. In the setting of acquired renal cystic disease, all solid tumors should be sampled as they may be associated with different morphologies.
|Figure 5: Gross specimen of a large renal cell carcinoma with sarcomatoid change|
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Multifocal renal tumors are seen to arise in hereditary conditions such as von Hippel–Lindau, Birt–Hogg–Dubé, fumarate hydratase–deficient RCC, tuberous sclerosis, hereditary papillary carcinoma, and other conditions such as renal oncocytosis and acquired kidney cystic disease.
- Gross assessment of tumor spread into the perinephric or renal sinus tissue:
This is important for staging purposes, and if present, the distance of the tumor from the closest fat margin should be measured, although it may be difficult to assess in the fresh state.
Tumor and the closest perinephric fat/renal sinus fat margin are recorded and section taken (if less than 10 mm).
The interface of the tumor with perinephric fat and renal sinus should be adequately sampled.
Gerota's fascia is the plane of surgical dissection and, though not visible microscopically, is considered to be involved when the tumor extends to the inked margin of the perinephric fat.
Perinephric fat invasion is a component of TNM staging (pT3a). Since a pushing margin alone is not confirmatory, microscopic assessment is necessary to declare perinephric fat invasion. The renal sinus is anatomically significant for tumor spread since it ensures direct contact between the tumor, fat, connective tissue, and vasculature in the renal sinus. There is no capsule separating it from the renal parenchyma. As it represents the main route of extrarenal spread, renal sinus invasion is of prognostic importance and is known to be a better indicator of tumor aggressiveness than perinephric fat invasion. The probability of such invasion increases when tumor size exceeds 40 mm and is highly likely when the tumor size is beyond 70 mm. If renal sinus fat invasion is grossly evident, or absent (e.g. small peripheral tumor), then one should sample only one block to confirm, if sinus invasion is present or absent. If the renal fat sinus invasion is uncertain, then one should sample at least three blocks of tumor–sinus interface.
- Sampling of pelvicalyceal system:
Pelvicalyceal system is examined for the presence of gross invasion. Invasion of the renal pelvicalyceal system by RCC was not addressed in the prior AJCC TNM 7th edition, but this has been added as an additional route of extension (pT3a) in the AJCC TNM 8th edition. A finger-like or polypoid nodule of the tumor within the collecting system would be considered to be pT3a [Figure 6]. Intuitively, it might be expected that tumors that invade the renal collecting system would have usually invaded the renal sinus prior to doing so; however, theoretically, extension to the medullary tip could result in collecting system involvement without renal sinus invasion. Although data are limited, there is some evidence that this affects prognosis. A meta-analysis study, which included 17 studies and more than 9,000 patients, showed that its presence has a negative impact on overall survival and recurrence-free survival.
|Figure 6: Gross specimen of renal cell carcinoma showing invasion into the renal sinus and renal vein|
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- Sampling of the renal pelvis:
This helps distinguish collecting duct carcinoma from urothelial carcinoma, which is seen to arise from pelvicalyceal urothelium. Microscopic presence of urothelial carcinoma in situ would clinch the diagnosis of urothelial carcinoma over a collecting duct RCC.
- Sampling the interface of the tumor with normal renal parenchyma:
This not only helps to assess the relation of the tumor with its surroundings but also helps in the evaluation of immunohistochemistry by providing an internal control.
- Sampling the uninvolved renal parenchyma:
The renal parenchyma should be sampled distant from the tumor. Numerous recent studies emphasize the need to assess nonneoplastic parenchyma, especially in radical/simple nephrectomies (where there is no nephron-sparing), to rule out other renal pathologies as well as peritumoral changes that might accentuate the compromise in renal function. Commonly reported conditions in such settings include arterionephrosclerosis/hypertensive nephropathy and diabetic nephropathy. According to different studies, 5 mm of Non-neoplastic renal parenchyma is required for evaluation.
- The following blocks should be submitted while grossing simple and radical nephrectomy specimens:
- Tumor generously sampled from different areas for typing and grading.
- Tumor sampled with areas of suspected perinephric fat invasion and renal sinus invasion.
- Tumor and the closest perinephric fat/capsular margin and renal sinus margin (if less than 10 mm).
- Renal vein/IVC with thrombus.
- Renal vein/IVC margin, renal artery margin, and ureteric margin.
- Any focal ureteric lesion.
- Tumor with pelvicalyceal system.
- Adjacent renal pelvis.
- Interface of the tumor with normal renal parenchyma.
- Uninvolved parenchyma, as distant as possible from the tumor (ideally more than 5 mm).
- Any other incidental or satellite lesions.
- Adrenal gland (if included, for metastases, contiguous spread, or incidental adrenal pathology).
- All hilar lymph nodes.
The principles of grossing these specimens are the same as above. The important points to be considered are as follows:
- Apart from inking the parenchymal resection margin, the external margin/perinephric fat margin should be inked, if suspicious for involvement by the tumor.
- The specimen should be sliced perpendicular to the parenchymal resection margin, as this will enable measurement of the maximum size of the tumor.
- Distance of tumor from the surgical margin should be measured, grossly.
The significance of a positive surgical margin (on microscopy) for patients who undergo partial nephrectomy remains controversial. Based on the presence of positive surgical margin (PSM) in microscopy, nephrectomies are classified as R0, when parenchymal margins are negative, and R1, when positive for tumor. Several studies show that the presence of R1 findings in grossly tumor-free parenchymal surgical margins do not impact tumor-free survival. A literature review of 3,803 cases showed that a positive margin (R1) in partial nephrectomy specimens rarely correlates with tumor recurrence and that a negative margin (R0) does not exclude the risk of recurrence. Some evidence suggests that even with a PSM, the remaining tumor burden can be destroyed by cautery used on the resection bed by the surgeons. Additionally, surgeons attempt to maximize the number of nephrons spared by aiming for smaller margins by performing enucleation. The relatively high false-negative rate, controversy over the prognosis of a positive margin, and inconsistency in influencing intraoperative management are arguments against the routine use of frozen sections in cases undergoing partial nephrectomy.
Nonetheless, reporting margin status is considered an essential part of histology reports, and the presence of R1 status when the resection bed is grossly tumor-free calls for surveillance rather than a second surgery.
- The following blocks should be submitted while grossing partial nephrectomy specimens:
- Tumor generously sampled for typing and grading.
- Tumor sampled with areas of suspected perinephric fat invasion, and (if included) renal sinus invasion.
- Tumor and the closest parenchymal margin.
- Tumor and the closest perinephric fat/capsular margin (if less than 10 mm).
- Uninvolved parenchyma, as distant as possible from the tumor (ideally more than 5 mm).
Due to the increase in the use of laparoscopic nephrectomies and a decrease in the incidence of positive ipsilateral lymph nodes (<10% cases), regional lymph node dissection is becoming uncommon.
Regional lymph nodes include hilar, abdominal aortic, and caval lymph nodes.
Specimens are usually measured in three dimensions. Lymph nodes are identified by palpation and the number recorded. They are described as either macroscopically normal or involved by the tumor. If there is a visible nodal metastasis, the size should be recorded, as this may be relevant for further treatment decisions. Grossly involved lymph nodes do not require processing in their entirety, but should be sampled to confirm metastatic deposits. If extranodal tumor extension is suspected grossly, such areas should also be selected for blocking.
| » Conclusion|| |
Adult renal tumors are a heterogeneous group of tumors with some unusual clinical and pathological characteristics that contrast with those of other cancers. Meticulous recognition of gross features and representative sampling is very crucial in rendering accurate diagnostic and prognostic information. Scrupulous grossing and sampling following current protocols are key to proper staging and prognostication of these tumors. The AJCC eighth edition introduces some (minor) staging changes and refines some definitions but retains most of the seventh-edition parameters.
| » Acknowledgments|| |
The authors wish to express their thanks for the following: Photo courtesy by the Department of Pathology, Sri Ramachandra Medical College and Research Institute, Chennai.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]