The Value of Histologic Subtyping on Outcomes of Clear Cell and Papillary Renal Cell Carcinomas: A Meta-analysis

Morphologic subtyping as a prognostic predictor for survival in papillary renal cell carcinoma: Type 1 vs. type 2

OBJECTIVE

To evaluate outcomes of surgically treated patients with clinically localized papillary renal cell carcinoma (RCC) and determine if papillary RCC subtype is associated with recurrence and survival.

METHODS

This is a historical cohort study using the prospectively maintained Canadian Kidney Cancer Information System database between January 2011 and September 2018. All patients underwent partial or radical nephrectomy. Patient, tumor, treatment, and outcomes were compared between papillary RCC type 2 and type 1 cohorts.

RESULTS

During the study period, 509 patients had clinically localized papillary RCC type 2 (n = 172) or type 1 (n = 337) histology. Sex, race, and comorbidities were similar between groups. Pathologic stage (pT3 or pT4), nuclear grade (3 or 4), and tumor diameter were higher in the type 2 papillary RCC cohort (P < 0.0001). A greater proportion of type 2 papillary RCC patients received radical nephrectomy (42.4% vs. 24.6%, P< 0.0001). More type 2 papillary RCC patients underwent lymph node dissection (19.6% vs. 5.5%, P< 0.0001) and had lymph node metastases removed during surgery (6.4% vs. 0.6%, P= 0.103). Overall, adjusting for age, grade, pathologic stage, positive nodes, and tumor size, type 2 papillary RCC had worse outcomes compared to type 1, as demonstrated by elevated all-cause mortality (hazard ratio = 7.7 [95% confidence interval: 2.0-28.9]), P=0.0027) and worse recurrence-free survival (hazard ratio = 8.2 [95% confidence interval: 3.6-19.0], P< 0.0001).

CONCLUSION

Patients with clinically localized type 2 papillary RCC present with higher risk disease and have worse prognosis compared to patients with clinically localized type 1 papillary RCC. To the best of our knowledge, this is the largest cohort study comparing papillary RCC subtypes.

Cystic renal cell carcinoma carries an excellent prognosis regardless of tumor size

INTRODUCTION

Cystic renal cell carcinoma (cystic RCC) is thought to carry an improved prognosis relative to clear cell RCC (CCRCC); however, this is based on small case series. We used a population-based tumor registry to compare clinicopathologic features and cancer-specific mortality (CSM) of cystic RCC with those of CCRCC.

MATERIALS AND METHODS

The Surveillance, Epidemiology, and End Results database was queried for all patients diagnosed and treated for cystic RCC and CCRCC between 2001 and 2010. Clinical and pathologic factors were compared using t tests and chi-square tests as appropriate. Kaplan-Meier survival analysis compared CSM differences between cystic RCC and CCRCC.

RESULTS

A total of 678 patients with cystic RCC and 46,677 with CCRCC were identified. The mean follow-up duration was 52 and 40 months, respectively. When compared with CCRCC patients, those with cystic RCC were younger (mean age 58 vs. 61 y, P < 0.001), more commonly black (22% vs. 9%, P < 0.001), and female (45% vs. 41%, P = 0.02). Cystic RCCs were more commonly T1a tumors (66% vs. 55%, P < 0.001), well differentiated (33% vs. 16%, P < 0.001), and smaller (mean size = 3.8 vs. 4.5 cm, P < 0.001). Cystic RCC was associated with a reduction in CSM when compared with CCRCC (P = 0.002). In a subset analysis, this reduction in CSM was seen only for those with T1b/T2 tumors (P = 0.01) but not for those with T1a RCCs lesions (P = 0.31).

CONCLUSIONS

We report the largest series of cystic RCC and corroborate the findings of improved CSM when compared with CCRCC for larger tumors; however, no difference was noted in smaller tumors, suggesting that tumor biology becomes more relevant to prognosis with increasing size. These data may suggest a role for active surveillance in appropriately selected patients with small, cystic renal masses.

Survival analysis of surgically treated renal cell carcinoma: a single Chinese medical center experience from 2002 to 2012

OBJECTIVES

To analyze the survival and the associated factors affecting the prognosis of renal cell carcinoma (RCC) in China with a sufficiently large sample size.

METHODS

Clinical data with complete follow-up of 1326 RCC patients were successfully obtained. Progression-free survival (PFS) and cancer-specific survival (CSS) were calculated, survival analysis was performed by Kaplan-Meier analysis, and Cox proportional hazards regression models were served to estimate the prognostic significance of each variables.

RESULTS

The median length of follow-up was 43.55 months (25-75 %, 25.47-68.75 months). During follow-up, 147 patients developed RCC-related progression, with a median PFS of 18.2 months (25-75 %, 7.50-47.27); 64 patients died from RCC-related progression, with a median CSS of 27.67 months (25-75 %, 14.10-58.53). For RCC patients in T1 stage, 3-, 5-, 8-, and 10-year CSS rates of patients receiving nephron-sparing nephrectomy were 99.33, 98.21, 97.40, and 97.40 %, respectively, which were significantly higher than radical nephrectomy patients (97.88, 96.28, 95.09, and 88.58 %, respectively). Cox proportional hazards regression model showed that tumor N stage, signs of lung metastasis (such as cough and hemoptysis), signs of bone metastasis (such as bone pain and fracture), pathological subtype of RCC, microscopic sarcomatoid change, and progression were prognosis factors for Chinese RCC patients.

CONCLUSIONS

Tumor stage, nephrectomy type, lung metastasis, bone metastasis, pathological subtype, sarcomatoid change, and type of progression were important risk factors for RCC. For T1 stage RCC patients, nephron-sparing nephrectomy showed better CSS than radical nephrectomy, which may guide the doctors and patients in their choices of surgical procedures.

[A case of papillary renal cell carcinoma type 2 resistant to sunitinib responded to second line therapy with axitinib]

According to previous studies, papillary renal cell carcinoma (pRCC) type 2 is known to have a poor prognosis, especially in cases with metastases. We report a case of pRCC that responded well to axitinib administered as second line therapy. The patient was a 52-year-old woman who presented at our hospital with an incidental tumor on the left kidney. She underwent laparoscopic radical nephrectomy, and the pathological diagnosis was pRCC type 2, grade 3 pT1b. Multiple lung and bone metastases were observed following the four months, and histological findings of lung metastases was metastatic RCC. Although sunitinib was administered as first line therapy, tumor progression was observed after the first cycle of treatment. Therefore, axitinib (10 mg/day) was administrated as second-line therapy and was gradually increased to 14 mg/day. Five months after the administration of axitinib, the maximum tumor diameter of the lung metastases reduced by 83%. At present, eight months have passed since the start of axtinib administration, but the response was still maintained and the adverse events were generally tolerable.

Racial disparity in renal cell carcinoma patient survival according to demographic and clinical characteristics

BACKGROUND

Patients with renal cell carcinoma (RCC) who are black tend to have poorer prognosis than similar patients who are white. This study examined whether the racial disparity in RCC patient survival varies by demographic and clinical characteristics.

METHODS

Nearly 40,000 patients (4359 black and 34,991 white) diagnosed with invasive RCC from 1992 to 2007 were identified from 12 registries in the National Cancer Institute Surveillance, Epidemiology, and End Results program, covering approximately 14% of the US population. Relative survival rates through 2008 were computed using the actuarial method.

RESULTS

Proportionally more blacks than whites were diagnosed with RCC under age 50 and with localized cancer. Overall, the 5-year relative survival rates were 72.6% (95% confidence interval 72.0%-73.2%) for white and 68.0% (66.2%-69.8%) for black patients. Survival was higher among women than men and among younger than older patients. Survival decreased with advancing tumor stage and, within each stage, decreased with increasing tumor size. Patients with clear cell RCC, a more common form among whites, had poorer prognosis than patients with papillary or chromophobe subtypes, which are more common among blacks. Survival for patients who received no surgical treatment (10.5% of white patients and 14.5% of black patients) was substantially lower than for patients treated with nephrectomy, with similar survival among whites and blacks. In all other demographic and clinical subgroups of patients, whites consistently had a survival advantage over blacks.

CONCLUSIONS

Patients with RCC who are white consistently have a survival advantage over those RCC patients who are black, regardless of age, sex, tumor stage or size, histological subtype, or surgical treatment.

Histologic variants of renal cell carcinoma: does tumor type influence outcome?

Each histologic type of renal cell carcinoma (RCC) has different pathologic and clinical parameters; however, the independent role of histologic type in outcome prediction remains contested. Most studies show relevance for outcome of each histologic type when correlated with survival by univariate analysis, whereas few studies show differences in outcome once other key prognostic factors, such as stage and grade, are considered. These studies highlight the challenges to prove outcome relevance. Despite the contested independent value of type for outcome prediction, separation of RCC into types is well accepted and can be substantiated on clinical, pathologic, molecular, and general outcome differences.