Renal cell carcinoma with mixed features of papillary and clear cell cytomorphology: a fluorescent in situ hybridization study

The efficacy of molecular targeted therapy and nivolumab therapy for metastatic non-clear cell renal cell carcinoma: A retrospective analysis using the Michinoku Japan urological cancer study group database

OBJECTIVES

To investigate the efficacy of pharmacotherapy for metastatic non-clear cell renal cell carcinoma (nccRCC) in Japanese population.

METHODS

In this retrospective analysis, we compared the time to treatment failure (TTF) for molecular-targeted agents as first-line therapy, or nivolumab therapy as sequential therapy between ccRCC and nccRCC using the data of Japanese metastatic RCC patients registered in the Michinoku Japan Urological Cancer Study Group database.

RESULTS

In total, 511 cases of ccRCC and 77 cases of nccRCC were treated with pharmacotherapy. After excluding the patients who received cytokine therapy, chemotherapy, or others, there were 391 ccRCC patients and 60 nccRCC patients who were treated with tyrosine kinase inhibitors (TKIs), and 7 ccRCC patients and 7 nccRCC patients who were treated with mammalian-target of rapamycin inhibitors (mTORIs). In addition, 132 ccRCC patients and 16 nccRCC patients received nivolumab. There was no significant difference in IMDC risk classification before first-line therapy between ccRCC and nccRCC groups, or in each subgroup within the nccRCC group. TTF for TKIs (161 days, 95% CI: 75-212 days) and mTORIs (21 days, 95% CI: 9-31 days) didn't differ significantly between nccRCC and ccRCC groups (205 days, 95% CI: 174-243 days and 33 days, 95% CI: 8-113 days, respectively). TTF for TKIs was significantly longer than that for mTORIs in nccRCC group (p<0.01). There was no significant difference in TTF between the different TKIs in nccRCC group. In addition, no significant difference in TTF for nivolumab was seen between ccRCC and nccRCC groups.

CONCLUSIONS

The results showed that the efficacy of molecular-targeted agents as first-line therapy was similar oncological outcomes between metastatic nccRCC and ccRCC in Japanese patients. TKIs may be more effective than mTORIs in metastatic nccRCC patients. Nivolumab administration might also be as effective in nccRCC patients as in ccRCC patients in Japanese population.

Clinical Utility of Fluorescence In Situ Hybridization (FISH) for Deletion of Chromosome 3p in the Work-up of Renal Masses

Chromosome 3p deletion is a well-established genetic aberration in clear cell renal cell carcinoma (RCC). We aimed to evaluate the clinical utility of 3p fluorescence in situ hybridization (FISH) on formalin-fixed paraffin-embedded tissue in surgical pathology specimens. 3p:3q <0.8 was established as the cut-off for 3p loss. The 2015 Medicare allowable billing rates were used to estimate the cost. Over 2.5 years (2013 to 2015), 3p FISH was performed on 18 cases per year. Among tested cases, 70% (30/43) were nephrectomies and 30% (14/43) metastases. 3p loss was detected in 44% (19/43) of cases, with a higher rate of loss in radical compared with partial nephrectomies (71% vs. 15%; P=0.003). A definitive RCC subtype was assigned in 65% (28/43) of cases. More partial nephrectomies had a definitive subtype assigned, compared with radical nephrectomies (92% vs. 59%; P=0.04), possibly related to more high-grade, high-stage tumors in submitted radical nephrectomies. Tested nephrectomies were most commonly diagnosed as clear cell (41%) or clear cell papillary RCC (32%). Half of unclassifiable RCCs had 3p loss (53%, 8/15). Annual 3p FISH costs were $3446.64, with 79% of costs from ancillary studies attributable to immunostains. 3p FISH was performed infrequently in nephrectomy specimens and was not cost prohibitive. RCC cases that are unclassifiable by morphology and other ancillary tests, but which have 3p FISH deletion may merit a comment in the pathology report, raising the possibility of clear cell RCC, as the oncologic approach may be altered despite the lack of a definitive RCC subtype.

Papillary or pseudopapillary tumors of the kidney

Papillary architecture is one of the most common morphological patterns in renal cell neoplasms. Many renal cell neoplasms can also exhibit, diffusely or focally, papillary growth pattern. This article reviews all the renal cell neoplasms with papillary or pseudopapillary architecture, with an emphasis on recently described new histological types. New insights into the "old" entities, including their immunohistochemical and genetic features, will also be discussed.

Systemic therapy for non-clear cell renal cell carcinomas: a systematic review and meta-analysis

CONTEXT

Clinical data supporting the use of targeted agents for the treatment of metastatic renal cell carcinoma (RCC) are based predominantly on patients with clear cell histology. Little is known about the efficacy of these drugs in non-clear cell variants.

OBJECTIVE

To evaluate the efficacy of different clear cell RCC (ccRCC)-approved targeted agents among patients with non-ccRCC compared with ccRCC.

EVIDENCE ACQUISITION

We conducted a systematic review of electronic databases to identify publications evaluating the outcomes of patients with non-ccRCC treated with targeted agents approved for treatment of ccRCC. Patients with sarcomatoid variant RCC were excluded from the main analysis but were evaluated as an independent cohort. End points of interest were response rate, median progression-free survival (PFS), and median overall survival (OS). Where possible, data were pooled in a meta-analysis. For studies of unselected patients with RCC, the outcomes of patients with non-ccRCC histology were compared with ccRCC. In exploratory analyses, outcomes of non-ccRCC with nonapproved agents were assessed.

EVIDENCE SYNTHESIS

A total of 49 studies comprising 7771 patients were included in the analysis. Of these, 1244 patients (16.0%) had non-ccRCC, 6300 (83.1%) had ccRCC, and 227 (2.9%) had sarcomatoid tumours. The overall response rate for non-ccRCC with targeted agents was 10.5%. In studies directly comparing non-ccRCC and ccRCC, there were significantly lower response rates for non-ccRCC (odds ratio for response: 0.52; 95% confidence interval, 0.40-0.68; p<0.001). For non-ccRCC treated with targeted agents, median PFS and OS were 7.4 and 13.4 mo, respectively; for patients with ccRCC, these were 10.5 mo and 15.7 mo, respectively (p value for difference<0.001 for both parameters).

CONCLUSIONS

Patients with non-clear cell renal cell carcinoma (non-ccRCC) have significantly lower response rates and poorer median progression-free survival and overall survival than those with ccRCC. The optimal treatment of patients with non-ccRCC remains unclear and warrants further study.

PATIENT SUMMARY

Systemic treatments for patients with renal cell carcinoma (RCC) tend to be significantly less effective for non-clear cell RCC, with lower response rates and worse progression-free survival and overall survival when compared with clear cell RCC. Optimal therapy remains unclear and warrants further study.

Papillary renal cell carcinoma revisited: a comprehensive histomorphologic study with outcome correlations

Papillary renal cell carcinoma (P-RCC) is the second most common type of malignant renal epithelial tumor and can be subclassified into type 1, which demonstrates simple cuboidal low-grade epithelium and type 2, which demonstrates pseudostratified high-grade epithelium with abundant eosinophilic cytoplasm. Despite this clinically useful subclassification, P-RCCs exhibit considerable histomorphologic diversity, with many cases having features differing from classically described type 1 and type 2 tumors. To our knowledge, there has been no recent study that has methodically evaluated the histomorphologic features of a series of P-RCCs. To address this, we evaluated a cohort of P-RCCs diagnosed between 1997 and 2004 with long-term clinical follow-up data (n = 56). Histomorphologic features previously described in the spectrum of type 1 and type 2 P-RCCs were recorded for each tumor, including nuclear grade, complete tumor capsule, and cytoplasmic eosinophilia as well as several other features. The current TNM staging (American Joint Committee on Cancer, seventh edition) was assigned to all cases. Histomorphologic features were diverse, demonstrating classic type 1 P-RCC and classic type 2 P-RCC morphology and several tumors with nonclassic features. Four patients in this cohort had distant metastasis. The primary tumor was equally divided between type 1 (2 cases) and type 2 (2 cases) morphology in the cases with metastasis. All P-RCC cases with metastases demonstrated presence of high nuclear grade and high tumor stage in the primary tumor. Cluster analysis using staging parameters and histomorphologic features divided tumors into 2 primary clusters. All primary tumors associated with metastasis were in the same cluster.

Analysis of molecular cytogenetic changes in metastatic renal cell carcinoma in the setting of everolimus treatment: a pilot project

BACKGROUND

The mTOR inhibitors have improved outcomes for patients with metastatic renal cell carcinoma (mRCC) but the duration of benefit is variable. Currently there are no predictive biomarkers for preselecting patients who are more likely to benefit from these agents. We undertook an exploratory translational study evaluating molecular cytogenetic changes in the context of outcomes from treatment with everolimus.

PATIENTS AND METHODS

Ten patients with clear cell mRCC treated with everolimus were enrolled. Pretreatment tissue specimens were analyzed for molecular cytogenetic changes using fluorescence in situ hybridization and progression-free survival (PFS) data were obtained. Gene probes chosen for this analysis were: Von Hippel Lindau, fragile histidine triad, fibroblast growth factor receptor (FGFR) 1, FGFR3, PDGFβ, PDGFRβ, epidermal growth factor receptor, and myelocytomatosis viral oncogene.

RESULTS

Median PFS was 8.75 months. Two patients with the longest PFS (28 months and 23 months) had gain of PDGFβ and PDGFRβ. This was also observed in 3 other patients who had a PFS of 11.5 months, 8 months, and 5.5 months, respectively. Cytogenetic evolution was observed between primary and metastatic specimens.

CONCLUSION

PDGFβ and PDGFRβ gene status might be of relevance to everolimus therapy. Further research evaluating the utility of these potential biomarkers is required.

Differential diagnosis of renal tumors with clear cytoplasm: clinical relevance of renal tumor subclassification in the era of targeted therapies and personalized medicine

CONTEXT

The World Health Organization classification of renal tumors synthesizes morphologic, immunohistochemical, and molecular findings to define more than 40 tumor types. Of these, clear cell (conventional) renal cell carcinoma is the most common malignant tumor in adults and-with the exception of some rare tumors-the most deadly. The diagnosis of clear cell renal cell carcinoma on morphologic grounds alone is generally straightforward, but challenging cases are not infrequent. A misdiagnosis of clear cell renal cell carcinoma has clinical consequences, particularly in the current era of targeted therapies.

OBJECTIVE

To highlight morphologic mimics of clear cell renal cell carcinoma and provide strategies to help differentiate clear cell renal cell carcinoma from other renal tumors and lesions. The role of the pathologist in guiding treatment for renal malignancies will be emphasized to stress the importance of proper tumor classification in patient management.

DATA SOURCES

Published literature and personal experience.

CONCLUSIONS

In challenging cases, submission of additional tissue is often an inexpensive and effective way to facilitate a correct diagnosis. If immunohistochemical stains are to be used, it is best to use a panel of markers, as no one marker is specific for a given renal tumor subtype. Selection of limited markers, based on a specific differential diagnosis, can be as useful as a large panel in reaching a definitive diagnosis. For renal tumors, both the presence and absence of immunoreactivity and the pattern of labeling (membranous, cytoplasmic, diffuse, focal) are important when interpreting the results of immunohistochemical stains.

Targeted therapies and the treatment of non-clear cell renal cell carcinoma

BACKGROUND

Targeted therapies have shown profound effects on the outcome of patients with advanced renal cell carcinoma (RCC). However, the optimal treatment for RCC of non-clear cell histology (nccRCC)-typically excluded from trials of targeted agents-remains uncertain.

MATERIALS AND METHODS

By carrying out extensive searches of PubMed and ASCO databases, we identified and summarised research into the biological characteristics, clinical behaviour and treatment of different histological subtypes of nccRCC, focusing on targeted therapy.

RESULTS

The available data suggest that treatments currently approved for RCC are active in ncc subtypes, although the overall clinical benefit may be less than for clear cell RCC. Temsirolimus has proven benefit over interferon-alfa (IFN-α) in patients with nccRCC, based on phase III data, while everolimus, sunitinib and sorafenib have all demonstrated some degree of activity in nccRCC in expanded-access trials. No clear picture has emerged of whether individual histological subtypes are particularly responsive to any individual treatment.

CONCLUSIONS

Further molecular studies into the pathogenesis of RCC histological subtypes will help direct the development of novel, appropriate targeted agents. Clinical trials specifically designed to evaluate the role of targeted agents in nccRCC are ongoing, and data from trials with sunitinib and everolimus will be reported soon.

Clear cell papillary renal cell carcinoma: differential diagnosis and extended immunohistochemical profile

Clear cell papillary renal cell carcinoma is a recently recognized renal neoplasm, composed of cells with clear cytoplasm lining cystic, tubular, and papillary structures. These tumors have immunohistochemical and genetic profiles distinct from clear cell renal cell carcinoma and papillary renal cell carcinoma. We studied morphologic and immunohistochemical features (cytokeratin 7 (CK7), carbonic anhydrase IX (CAIX), CD10, alpha-methylacyl-CoA racemase, smooth muscle actin, desmin, estrogen and progesterone receptors) in 55 tumors from 34 patients, 8 of whom had end-stage renal disease. These tumors comprised 3% of all adult renal cell carcinoma resections over a period of 3 years. The patients' ages ranged from 33 to 87 years (mean 61). Multiple tumors (2-8) were present in 9 patients. Other renal tumors were present concurrently in four patients and subsequently in two patients, including: oncocytoma, clear cell renal cell carcinoma, and multilocular cystic renal cell carcinoma. Sizes ranged from 0.2 to 7.5 (mean 2.0) cm; 87% were Fuhrman grade 2, and 96% were stage pT1a. Papillary architecture was usually limited to focal branching papillae (51% of 55 tumors) or small, blunt papillae (35%). Large areas of extensively branched papillae were present in only 14% of tumors. Almost all tumors (98%) included cysts, and 18 tumors were extensively (≥90%) cystic. Immunoprofile showed CK7+, AMACR-, CD10-, CAIX+ in the tubular and papillary components of all tumors; however, CD10 labeled the apical cell membrane of cyst epithelium in 59%. The stroma was focally actin positive (94%), with infrequent desmin expression (13%). Estrogen receptor and progesterone receptor were negative. During a median follow-up period of 56 months, no patient developed local recurrence, distant or lymph-node metastasis, or cancer death. Branched tubules, small papillae, and the immunohistochemical and molecular profiles aid in distinguishing these tumors from clear cell renal cell carcinoma and multilocular cystic renal cell carcinoma.

Renal cell carcinoma with clear cell and papillary features

CONTEXT

The diagnosis of primary renal cell carcinomas (RCCs) with both papillary architecture and cells with clear cytoplasm can be diagnostically challenging for practicing pathologists. The 4 main neoplasms in the differential diagnosis are clear cell RCC, papillary RCC, clear cell papillary RCC, and Xp11 translocation RCC. Accurate diagnosis has both prognostic and therapeutic implications.

OBJECTIVE

To highlight the helpful cytomorphologic, immunohistochemical, and cytogenetic features of each of these entities to enable reproducible classification.

DATA SOURCES

Published peer-reviewed literature was reviewed, accompanied by the authors' personal experiences.

CONCLUSIONS

Key morphologic clues and a focused immunohistochemical panel, including CK7, α-methylacyl coenzyme A racemase (AMACR), TFE3, cathepsin K, and carbonic anhydrase IX (CAIX), now allow most resected RCCs with papillary architecture and clear cells to be accurately classified. In other cases, cytogenetic and molecular findings can establish the diagnosis. Despite these tools, some RCCs with papillary architecture and clear cells do not fit into any of the described entities and currently remain unclassified.

Clear-cell papillary renal cell carcinoma: 24 cases of a distinct low-grade renal tumour and a comparative genomic hybridization array study of seven cases

AIMS

To report clinicopathological and genomic characteristics of (ccpRCC), a rare, recently characterized renal tumour entity.

METHODS AND RESULTS

Twenty-four renal tumours identified as ccpRCC were collected. Data from comparative genomic hybridization on microarrays (array-CGH) were obtained for seven of these. Most tumours (58%) occurred in the absence of renal disease. Mean patient age was 58.1 years. Tumours were small (mean size: 2.4 cm) and classified as pT1. Histological characteristics consisted of tubules and papillae lined by a single layer of small clear cells harbouring low-grade nuclei (Fuhrman grades 1 or 2). Architectural variations, with compact areas (41% of cases) and a micro- or macrocystic pattern (67% of cases) were observed frequently. Immunostaining demonstrated diffuse, strong expression of cytokeratin 7 and vimentin, whereas CD10, racemase, RCC antigen, translocation factor E3, TFE3 and translocation factor EB were consistently negative. In seven tumours, array-CGH detected no chromosomal imbalances.

CONCLUSIONS

Clear-cell papillary renal cell carcinoma (ccpRCC) were differentiated from other renal neoplasms by a specific constellation of histopathological and immunohistochemical features, without characteristic genomic imbalances. Clinical, histopathological and genomic data suggested that these tumours have a low potential for malignancy.

Renal-cell carcinomas in end-stage kidneys: a clinicopathological study with emphasis on clear-cell papillary renal-cell carcinoma and acquired cystic kidney disease-associated carcinoma

Clear-cell papillary renal-cell carcinoma (CCPC) and acquired cystic kidney disease-associated carcinoma (ACDAC) are neoplasms with distinct morphological characteristics that behave less aggressively than conventional renal-cell carcinomas. End-stage kidney specimens from 61 patients (47 males and 14 females) with 109 renal-cell carcinomas were selected. Papillary renal-cell carcinoma was the most common malignancy (61/109, 56%), followed by CCPC (20/109, 18%). The CCPC showed a papillary or tubular/solid architecture, clear cytoplasm, low nuclear grade, and a distinct immunohistochemical profile (RCC-, vimentin+, CK7+, p504S-). ACDAC displayed a variety of architectural patterns, eosinophilic cytoplasm, high nuclear grade, intratumoral calcium oxalate deposits, and an immunohistochemical profile similar to type 2 papillary renal-cell carcinoma (RCC+, vimentin+, CK7-/+, p504S+). Less than 5% (3/69) of pathologically staged renal-cell carcinomas in end-stage kidneys presented with lymphogenous and/or hematogenous metastases.

Clear cell tubulopapillary renal cell carcinoma: a study of 36 distinctive low-grade epithelial tumors of the kidney

Recently several low-grade renal cell tumors, distinct from those recognized by the 2004 World Health Organization classification of renal tumors, have been described. These tumors had similar clinicopathologic features, being low-stage tumors with cystic, tubuloacinar, and/or papillary architecture. The tumor cells were low grade with variable amounts of clear cytoplasm that was positive for cytokeratin 7 (CK7), but negative for CD10. Genetic changes characteristic of clear cell or papillary renal cell carcinoma were not seen in these tumors. We investigated the morphologic, immunohistochemical, and genetic features of 36 additional tumors. Immunohistochemistry was carried out for CK7, carbonic anhydrase 9, α-methylacyl-CoA racemase, CD10, TFE-3, and desmin. Interphase fluorescence in situ hybridization was carried out with centromeric probes for chromosomes 3, 7, 17, and a subtelomeric probe for 3p25. Sequencing of von Hippel-Lindau gene and analysis of the methylation status of the promoter region was also carried out in 2 tumors. Thirty-six tumors from 33 patients (mean age: 60.4 , range: 26 to 88; 17 men and 16 women) were studied. Three patients had bilateral tumors and 1 patient had von Hippel-Lindau disease. Follow-up was available in 60% (20/33) of the patients for a mean of 27.4 (range 1 to 85) months. No patient had evidence of the disease after surgery except for the patient with von Hippel-Lindau disease, who was alive with stable disease in the contralateral kidney. All 36 tumors were small (mean size 2.4 cm; range 0.9 to 4.5 cm) and low stage (pT1). The majority was cystic and had prominent fibrous capsule and stroma. The tumors were composed of variable amount of cysts, papillae, tubules, acini, and solid nests. The most characteristic histologic features were branching tubules and acini and anastomosing clear cell ribbons with low-grade nuclei. All tumors were strongly positive for CK7 and variably positive for CA9, but largely negative for CD10, and negative for α-methylacyl-CoA racemase and TFE-3. All but 1 tumor had no gains of chromosomes 7 and 17 and deletion of 3p. Only 1 tumor had low copy number gains of chromosomes 7 and 17. VHL gene mutation and promoter methylation were negative in 2 tumors analyzed. We show that these tumors, which we term as "clear cell tubulopapillary renal cell carcinoma," constitute a unique subtype in the spectrum of renal epithelial neoplasia based on their characteristic morphologic and immunohistochemical features.