The Impact of Histological Variants on Oncological Outcomes After Surgical Resection of a Nonmetastatic Renal Cell Carcinoma with Tumor Thrombus: A Multi-institutional Study

Background

There is no definitive evidence of the prognosis impact of histological variants (HVs) in patients who undergo surgical resection of a nonmetastatic renal cell carcinoma (nm-RCC) with venous tumor thrombus (TT).

Objective

To investigate the impact of HVs on the prognosis of patients with nm-RCC with TT after radical surgery.

Design setting and participants

Patients who underwent radical nephrectomy with the removal of the venous TT for an nm-RCC were included in a retrospective study.

Outcome measurements and statistical analysis

Three groups were identified: clear cell (ccRCC), papillary (pRCC), and chromophobe (chRCC) RCC. The primary outcome measures (disease-free and overall survival [OS]) were assessed using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate Cox proportional hazard models were used to study the impact of HVs on survival.

Results and limitations

A total of 873 patients were included. The histological subtypes were distributed as follows: ccRCC in 780 cases, pRCC in 58 cases, and chRCC in 35 cases. At the time of data analysis, 612 patients were recurrence free and 228 had died. A survival analysis revealed significant differences in both OS and recurrence-free survival across histological subtypes, with the poorest outcomes observed in pRCC patients (p < 0.05). In a multivariable analysis, pRCC was independently associated with worse disease-free survival and OS (hazard ratio [HR]: 1.71; p = 0.01 and HR: 1.24; p = 0.04), while chRCC was associated with more favorable outcomes than ccRCC (HR: 0.05; p < 0.001 and HR: 0.02; p < 0.001). A limitation of the study is its retrospective nature.

Conclusions

In this multicentric series, HVs appeared to impact the medium-term oncological prognosis of kidney cancer with TT.

Patient summary

This study investigated the differences in oncological outcomes among histological variants (clear cell, papillary, and chromophobe) in a cohort of nonmetastatic renal cell carcinoma patients with venous tumor thrombus extension. We observed that these histological variants within this specific subgroup exhibit distinct outcomes, with papillary renal cell carcinoma being associated with the worst prognosis.

Clinicopathological features and medium-term outcomes of histologic variants of primary focal segmental glomerulosclerosis in adults: A retrospective study

BACKGROUND

The Columbia classification identified five histological variants of focal segmental glomerulosclerosis (FSGS). The prognostic significance of these variants remains controversial.

AIM

To evaluate the relative frequency, clinicopathologic characteristics, and medium-term outcomes of FSGS variants at a single center in Pakistan.

METHODS

This retrospective study was conducted at the Department of Nephrology, Sindh Institute of Urology and Transplantation, Karachi, Pakistan on all consecutive adults (≥ 16 years) with biopsy-proven primary FSGS from January 1995 to December 2017. Studied subjects were treated with steroids as a first-line therapy. The response rates, doubling of serum creatinine, and kidney failure (KF) with replacement therapy were compared between histological variants using ANOVA or Kruskal Wallis, and Chi-square tests as appropriate. Data were analyzed by SPSS version 22.0. P-value ≤ 0.05 was considered significant.

RESULTS

A total of 401 patients were diagnosed with primary FSGS during the study period. Among these, 352 (87.7%) had a designated histological variant. The not otherwise specified (NOS) variant was the commonest, being found in 185 (53.9%) patients, followed by the tip variant in 100 (29.1%) patients. Collapsing (COL), cellular (CEL), and perihilar (PHI) variants were seen in 58 (16.9%), 6 (1.5%), and 3 (0.7%) patients, respectively. CEL and PHI variants were excluded from further analysis due to small patient numbers. The mean follow-up period was 36.5 ± 29.2 months. Regarding response rates of variants, patients with TIP lesions achieved remission more frequently (59.5%) than patients with NOS (41.8%) and COL (24.52%) variants (P < 0.001). The hazard ratio of complete response among patients with the COL variant was 0.163 [95% confidence interval (CI): 0.039-0.67] as compared to patients with NOS. The TIP variant showed a hazard ratio of 2.5 (95%CI: 1.61-3.89) for complete remission compared to the NOS variant. Overall, progressive KF was observed more frequently in patients with the COL variant, 43.4% (P < 0.001). Among these, 24.53% of patients required kidney replacement therapy (P < 0.001). The hazard ratio of doubling of serum creatinine among patients with the COL variant was 14.57 (95%CI: 1.87-113.49) as compared to patients with the TIP variant.

CONCLUSION

In conclusion, histological variants of FSGS are predictive of response to treatment with immunosuppressants and progressive KF in adults in our setup.

Histological variants and lymphovascular invasion in upper tract urothelial carcinoma can stratify prognosis after radical nephroureterectomy

OBJECTIVES

Patients with histological variants (HV) of bladder cancer have more advanced disease and poorer survival rates than those with pure urothelial carcinoma (UC). Moreover, lymphovascular invasion (LVI) is an important biomarker after RNU in systematic reviews and meta-analyses. Thus, here we investigated the clinical and prognostic impact of HV and LVI in patients with upper tract urothelial carcinoma (UTUC) treated with radical nephroureterectomy (RNU).

METHODS

Data from 223 UTUC patients treated with RNU without neoadjuvant chemotherapy were retrospectively evaluated. We analyzed differences in clinicopathological features and survival rates between patients with pure UC and those with HV. Conditional survival (CS) analysis was performed to obtain prognostic information over time.

RESULTS

A total of 32 patients (14.3%) had HV, with the most common variant being squamous differentiation, followed by glandular differentiation. UTUC with HV was significantly associated with advanced pathological T stage (pT ≥ 3), higher tumor grade (G3), and LVI, compared to pure UC (all P < 0.01). Progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS), were all significantly worse in the HV group compared to the pure UC group (all, P < 0.001). In multivariable analysis, HV and LVI were independent predictors of CSS and OS. We classified the patients into three groups using these two predictors: low-risk (neither HV nor LVI), intermediate-risk (either HV or LVI), and high-risk (both HV and LVI). Significant differences in PFS, CSS, and OS rates were found among the 3 groups. In CS analysis, the conditional PFS, CSS, and OS rates at 1, 2, 3, 4, and 5 years improved with increased duration of event-free survival. CS analysis revealed that most progression events occurred within 2 years after RNU, and patients with risk factors had worse PFS at all time points.

CONCLUSIONS

A risk model using HV and LVI can stratify PFS, CSS, and OS of patients treated with RNU. In addition, CS analysis revealed that HV and LVI were poor prognostic factors over time after RNU.

Oncological outcomes of concomitant carcinoma in situ at radical cystectomy in pure urothelial bladder cancer and in histological variants

INTRODUCTION

The presence of carcinoma in situ at transurethral resection is known to increase the risk of recurrence and progression to invasive disease. However, the evidence regarding the prognostic role of concomitant carcinoma in situ after radical cystectomy due to bladder cancer is controversial. Moreover, concomitant carcinoma in situ was found to be significantly associated with bladder histological variants. The aim of our study is to evaluate whether the presence of concomitant carcinoma in situ at radical cystectomy, impacts on recurrence and survival outcomes in pure urothelial bladder cancer, compared to histological variants.

METHODS

We evaluated 410 consecutive patients diagnosed with non-metastatic bladder cancer and treated with radical cystectomy at a single tertiary referral centre between January 2009 and May 2019. Patients were stratified according to the presence of carcinoma in situ. The Kaplan-Meier method was used to compare recurrence free, cancer specific and overall survival in pure urothelial and histological variants. Cox proportional hazards regression analyses model was used to predict recurrence, cancer specific and overall mortality in pure urothelial and histological variants bladder cancer, according to pathological stage.

RESULTS

Median age was 71 years. 340 patients (82%) were male. At a median follow-up of 32 months, disease recurrence, cancer specific mortality and overall mortality were, 37% (155 patients), 32.9% (135 patients) and 46.6% (191 patients), respectively. Concomitant and pure carcinoma in situ were found in 39% and 19% of radical cystectomy specimens, respectively. Concomitant carcinoma in situ was more frequent in patients with histological variants (50.9%) compared to pure urothelial bladder cancer (35.4%) (P-value <.001) and was associated with worst pathological features (lymphovascular invasion, lymph node involvement and non-organ confined disease). Recurrence free survival at Kaplan-Meyer analyses was significantly higher in patients with pure carcinoma in situ compared to those with concomitant or no carcinoma in situ (all P <.001), similarly for patients without carcinoma in situ compared with those with concomitant Cis (P =.02) at radical cystectomy. Cancer specific and overall survival were significantly higher in patients with pure carcinoma in situ compared to those with concomitant or no carcinoma in situ (all P <.001). Conversely no significant difference was found between patients without carcinoma in situ and with concomitant carcinoma in situ (P>0.1) at radical cystectomy Moreover, concomitant carcinoma in situ at radical cystectomy in histological variants is associated with higher free recurrence rate compared to the other groups. At multivariate Cox proportional hazards regression analyses the presence of carcinoma in situ at radical cystectomy was not associated with any survival effect or recurrence (all P > .05) in the overall population and when patients are stratified according to histology. However, concomitant carcinoma in situ represents an independent predictor of recurrence in the subgroup of patients with organ confined disease in case of urothelial bladder cancer and histological variants.

CONCLUSION

Concomitant carcinoma in situ should be considered a proxy of aggressiveness in bladder cancer after radical cystectomy. Based on its prognostic implications, concomitant carcinoma in situ should be considered for strict follow-up in patients with organ confined disease which may deserve adjuvant treatment both in pure urothelial bladder cancer and histological variants.

Histological Variants of Urothelial Carcinoma Predict No Response to Neoadjuvant Chemotherapy

BACKGROUND

Platinum-based neoadjuvant chemotherapy (NAC) in muscle-invasive urothelial bladder cancer (MIBC) has been adopted as a standard of care related to better survival outcomes. However, there is a considerable number of patients who do not respond, experiencing toxicity and delay in the surgical treatment. Our aim is to find biomarkers of response that could be easily adopted in the clinical practice.

METHODS

Between January 2009 and July 2016, 52 patients with MIBC were submitted to radical cystectomy after NAC. A tissue microarray containing 25 cases, who met the inclusion criteria was built for immunohistochemical analysis of Cytokeratins 5/6, 7, and 20, GATA3, Her2, EGFR, p63, p53, Carbonic-anhydrase IX (CAIX), MLH1, MSH2, MSH6, and PMS2. The surgery was performed in a mean time of 58.7 (± 21) days after the end of the NAC. Fisher's exact test was used to analyze the relationship between response (≤pT1) and histopathological and immunohistochemical results and Kaplan-Meier curves were designed for survival analysis.

RESULTS

Ten (40.0%) patients presented response to NAC. Histological variants of the urothelial carcinoma characterized by squamous, sarcomatous/rhabdoid, plasmacytoid, and micropapillary was present in 36.0% and none responded to NAC (P = .002). CAIX was expressed by 53.3% and none responded to NAC (P= .005). Lymph-node metastasis, divergent differentiation, and expression of cytokeratin 5/6 were related to short cancer specific survival.

CONCLUSION

Histological variants and CAIX immune-expression are biomarkers of nonresponse to NAC of MIBC, and might be easily used in the clinical practice to select patients to be submitted to surgery upfront.

Prognostic impact of molecular muscle-invasive bladder cancer subtyping approaches and correlations with variant histology in a population-based mono-institutional cystectomy cohort

Purpose

Recently discovered molecular classifications for urothelial bladder cancer appeared to be promising prognostic and predictive biomarkers. The present study was conducted to evaluate the prognostic impact of molecular subtypes assessed by two different methodologies (gene and protein expression), to compare these two approaches and to correlate molecular with histological subtypes in a consecutively collected, mono-institutional muscle-invasive bladder cancer (MIBC) cohort.

Methods

193 MIBC were pathologically re-evaluated and molecular subtypes were assessed on mRNA (NanoString technology, modified 21-gene-containing MDACC approach) and protein levels (immuno-histochemical [IHC] analysis of CK5, CK14, CD44, CK20, GATA3 and FOXA1). Descriptive statistical methods and uni-/multi-variable survival models were employed to analyze derived data.

Results

Neither gene expression nor protein-based subtyping showed significant associations with disease-specific (DSS) or recurrence-free survival (RFS). Agreement between mRNA (reference) and protein-based subtyping amounted 68.6% for basal, 76.1% for luminal and 50.0% for double-negative tumors. Histological subtypes associated with RFS in uni-variable (P = 0.03), but not in multivariable survival analyses. Tumors with variant histology predominantly showed luminal subtypes (gene expression subtyping: 36/55 cases, 65.5%; protein subtyping: 44/55 cases, 80.0%). Squamous differentiation significantly associated with basal subtypes (gene expression subtyping: 44/45 squamous cases, 97.8%; protein subtyping: 36/45 cases, 80.0%).

Conclusion

In our consecutive cystectomy cohort, neither gene, protein expression-based subtyping, nor histological subtypes associated with DSS or RFS in multi-variably adjusted survival analyses. Application of a limited IHC subtyping marker panel showed high concordance of 83.9% with gene expression-based subtyping, thus underlining the utility for subtyping in pathological routine diagnostics. In addition, histological MIBC subtypes are strong indicators for intrinsic subtypes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-021-03788-1.

Accuracy of Transurethral Resection of the Bladder in Detecting Variant Histology of Bladder Cancer Compared with Radical Cystectomy

BACKGROUND

Correct identification of variant histologies (VHs) of bladder cancer (BCa) at transurethral resection of the bladder (TURB) could drive the subsequent treatment.

OBJECTIVE

To evaluate the concordance in detecting VHs between TURB and radical cystectomy (RC) specimens in BCa patients.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively analyzed 1881 BCa patients who underwent TURB and subsequent RC at seven tertiary care centers between 1980 and 2018. VHs were classified as sarcomatoid, lymphoepithelioma-like, neuroendocrine, squamous, micropapillary, glandular, adenocarcinoma, nested, and other variants.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Concordance between TURB and RC was defined as the ability to achieve histological subtypes at TURB confirmed at RC specimen, and was expressed according to Cohen's kappa coefficient.

RESULTS AND LIMITATIONS

Of the patients, 14.6% and 21% were diagnosed with VH at TURB and RC specimens, respectively. The most common VHs at TURB were squamous, neuroendocrine, and micropapillary carcinoma (5.2%, 1.5%, and 1.5%, respectively). At RC, the most frequent VHs were squamous, micropapillary, and sarcomatoid carcinoma (7.2%, 3.0%, and 2.7%, respectively). The overall concordance in detecting VH was defined as slight concordance (coefficient: 0.18). Moderate concordance was found for neuroendocrine, adenocarcinoma, and squamous carcinoma (coefficient: 0.49, 0.47, and 0.41, respectively). Micropapillary, glandular, and other variants showed slight concordance (coefficient: 0.05, 0.17, and 0.12, respectively), while nested and sarcomatoid carcinoma showed fair concordance (coefficient: 0.32 and 0.26, respectively). Results may be limited by the absence of centralized pathological analysis.

CONCLUSIONS

A non-negligible percentage of patients were diagnosed with VH at both TURB and RC. TURB showed relatively low accuracy, ranging from poor to moderate, in detecting VHs. Our study underlines the need of additional diagnostic tools in order to identify VHs properly at precystectomy time and to improve patient survival outcomes.

PATIENT SUMMARY

In this report, we underlined the low accuracy of transurethral resection of the bladder in detecting variant histologies and the need for additional diagnostic tools.

The impact of histological variants on outcomes after open radical cystectomy for muscle-invasive urothelial bladder cancer: results from a single tertiary referral centre

OBJECTIVES

To evaluate the impact of histological variants on oncological outcomes of patients with muscle-invasive bladder cancer treated with open radical cystectomy and furthermore to determine any association between survival and each histotype of bladder cancer.

MATERIALS AND METHODS

Data from 525 consecutive patients with muscle-invasive bladder cancer treated with radical cystectomy between January 2008 and May 2019 were collected retrospectively. The Kaplan-Meier curves and multivariable analysis addressed the role of histological variants in recurrence, cancer-specific and overall mortality between all subgroups.

RESULTS

Of 525 patients, 131 (25.0%) showed a histological variant at radical cystectomy. With a median follow-up of 31 months, 209 (39.8%) recurrences, 184 (35.0%) cancer-related deaths and 260 (49.5%) overall deaths were reported. The presence of histological variant was associated with advanced tumour stage, the presence of concomitant carcinoma in situ, lymph node metastasis, lymphovascular invasion and positive surgical margins compared to pure urothelial bladder cancer (all p values < .008) and resulted as an independent risk factor for cancer-specific mortality (p = 0.001). Patients with a histological variant were at significantly higher risk for recurrence, cancer-specific mortality and overall mortality (all p values ≤ .001). Micropapillary, sarcomatoid or small cell differentiation was associated with reduced survival.

CONCLUSION

The presence of histological variants at radical cystectomy seems to be weakly associated with reduced survival compared to pure urothelial bladder cancer paired for pathologic stage. The association of histological variants with advanced and biologically aggressive tumours suggests the need for attention on the overall management of these patients, in particular for micropapillary, sarcomatoid and small cell differentiation.

The evolving concept of aggressive histological variants of differentiated thyroid cancer

It is recommended by current clinical guidelines that pathologists identify and report aggressive histological variants of differentiated thyroid cancer (e.g., tall cell, columnar cell, and hobnail variants of papillary thyroid carcinoma; widely invasive follicular thyroid carcinoma). This review analyzes the historical evolution of these entities and highlights unresolved issues with respect to the diagnostic criteria for these tumors.

[Molecular biology, diagnosis, and therapy of meningiomas]. Pathologe. 2019;40:514-518. [PMID: 31435780 DOI: 10.1007/s00292-019-00653-2]

Meningiomas are the most frequent primary intracranial tumors. While about 80% are benign, slow-growing tumors, approximately 20% are characterized by aggressive biology, increased recurrence rate, and overall impaired prognosis. Over the last five years, several new findings on the molecular pathology of meningiomas have been published, suggesting a relationship between certain somatic mutations and both tumor localization and histological variant. The newly introduced methylation-based classification of prognostic subgroups will improve the assessment of the individual clinical course in meningioma patients.

Is transurethral resection alone enough for the diagnosis of histological variants? A single-center study

INTRODUCTION

To evaluate incidence of histological variants and grade agreement between transurethral resection (TUR) and radical cystectomy (RC) in patients with bladder cancer.

METHODS

A total of 779 patients treated with TUR and subsequently with RC between 1990 and 2013 at a single center were analyzed retrospectively. Variant histology classifications used in our analyses were sarcomatoid, small cell, squamous, or micropapillary. Grade agreement was calculated using the Cohen kappa coefficient. Logistic regression analyses were built to predict adverse pathologic features from histological variants at TUR.

RESULTS

Considering TUR, 213 (27.3%) patients were diagnosed with histological variants. Of these, 2.1% (n = 16) were found with sarcomatoid variant, 1.7% (n = 13) with small cell, 7.1% (n = 55) with squamous, 12.5% (n = 97) with micropapillary. Considering RC, 212 (27.2%) patients were diagnosed with histological variants. Poor agreement was found considering micropapillary variant and the presence of a histological variant in general (0.11 and 0.27, respectively). Intermediate agreement was found analyzing the presence of sarcomatoid, small cell, and squamous variants (0.43, 0.61, and 0.61, respectively). Small cell carcinoma at TUR was found associated with an increased risk of harboring positive soft tissue surgical margin (odds ratio = 2.08; CI: 1.27-3.41; P = 0.03).

CONCLUSIONS

One out of our patients with bladder cancer was diagnosed with a histological variant either at TUR and RC. We found poor agreement between TUR and RC. Our findings highlight that TUR alone is not sufficient to accurately evaluate the presence of histological variants that may have an effect on treatment and survival outcomes.

Incidence and effect of variant histology on oncological outcomes in patients with bladder cancer treated with radical cystectomy

INTRODUCTION

We sought to describe incidence of histological variants after radical cystectomy (RC) due to bladder cancer (BCa). Moreover, we investigated survival outcomes accounting for this parameter.

METHODS

We retrospectively evaluated data from 1,067 patients with BCa treated with RC between 1990 and 2013 at a single tertiary care referral center. All specimen were evaluated by dedicated uropathologists. Univariable and multivariable Cox regression analyses tested the effect of different histopathological variant on recurrence, cancer-specific mortality (CSM), and overall mortality (OM) after accounting for all available confounders.

RESULTS

Of 1,067 patients, 729 (68.3%) harbored pure urothelial BCa while 338 (31.7%) were found to have a variant. Considering uncommon variants, 21 (2.0%) were sarcomatoid, 10 (0.9%) lymphoepitelial, 19 (1.8%) small cell, 109 (10.2%) squamous, 89 (8.3%) micropapillary, 23 (2.2%) glandular, 34 (3.2%) mixed variants, and 33 (3.1%) were found with other types of variants. With a median follow-up of 6.2 years, 343 recurrence, 365 CSM, and 451 OM were recorded, respectively. At multivariable Cox regression analyses, the presence of small cell variant was associated with higher recurrence (hazard ratio [HR] = 3.47, P<0.001), CSM (HR = 3.30, P<0.04), and OM (HR = 2.97, P<0.003) as compared with pure urothelial cancer. Conversely, no survival differences were recorded considering other histological variants (all P> 0.1).

CONCLUSION

Our study confirms that histological variant is not an infrequent event at RC specimen. However, in our single-center series, only patients found with small cell variant were associated with a negative effect on survival after RC.

Pure but Not Mixed Histologic Variants Are Associated With Poor Survival at Radical Cystectomy in Bladder Cancer Patients

PURPOSE

To evaluate the impact of pure and mixed histologic variant versus pure urothelial carcinoma in nonmetastatic bladder cancer (BCa) patients treated with radical cystectomy (RC).

PATIENTS AND METHODS

We evaluated data from 1067 patients treated with RC and pelvic lymph node dissection between 1990 and 2013 at a single institution tertiary-care referral center. All specimens were evaluated by dedicated uropathologists. Univariable and multivariable Cox regression analyses tested the impact of the presence of pure and mixed histologic variants versus pure urothelial on recurrence, cancer-specific mortality, and overall mortality after accounting for all available confounders.

RESULTS

In total, 201 (19%) and 137 (13%) patients were found with mixed and pure variants at RC, respectively. Mixed preponderant variants were sarcomatoid, lymphoepitelial, squamous, and glandular; small-cell and micropapillary variants were found mostly as pure variants. With a median follow-up of 6.5 years, patients who harbored pure variant were found by multivariable analyses to have lower survival outcomes compared to pure urothelial carcinoma (all P < .01). Conversely, no differences were found between mixed variant versus pure urothelial by multivariable Cox regression analyses predicting recurrence, cancer-specific mortality, and overall mortality (all P > .1).

CONCLUSION

The presence of histologic variants at RC is a common finding, accounting for approximately 30% of specimens. In this setting, the presence of a pure variant but not the presence of mixed variant with urothelial carcinoma is related to a detrimental effect on survival outcomes after RC.

Keratoameloblastoma a rare entity: a case report

Ameloblastoma is the second most common odontogenic tumour of oral cavity; which has several different histological variants such as follicular, plexiform, acanthomatous, granular cell, desmoplastic, basal cell, clear cell, hemangiomatous, mucous cell differentiation and keratoameloblastoma. It is common in posterior mandible and has high male predilection in the ratio of 3:1. This report presents a case of keratoameloblastoma in 65-year-old female patient in the anterior mandible region with literature review on clinical features, histopathological findings, radiological appearance and treatment options.

Frequency and clinicopathological characteristics of variants of primary focal segmental glomerulosclerosis in adults presenting with nephrotic syndrome

BACKGROUND

BACKGROUND

There is no information on the frequency and clinicopathological presentation of the variants of primary focal segmental glomerulosclerosis (FSGS) in adults presenting with idiopathic nephrotic syndrome (INS) in Pakistan.

OBJECTIVES

The aim of this study was to determine the frequencies of different histologic variants of primary FSGS with INS at our center and to compare our findings with those published in literature.

PATIENTS AND METHODS

All consecutive adults (≥18 years) with INS, and diagnosis of FSGS on renal biopsies, were included. Their clinicopathological features at the time of presentation were retrieved and compared among the variants.

RESULTS

There were 120 (65.2%) males and 64 (34.8%) females. The mean age was 30.62±12.02 years. The mean 24-hr urinary protein excretion was 4.69±2.36 grams. Microscopic hematuria was found in 30 (16.3%) patients. The mean serum creatinine was 1.58±0.87 mg/dL. At presentation, 128 (69.6%) patients were normotensive, while 56 (30.4%) exhibited hypertension. FSGS, not otherwise specified (NOS) was the predominant variant, comprising 76.6% of all; collapsing variant comprised 12%, tip variant, 9.8%, perihilar, 1.1%, and cellular, 0.5%. The mean number of glomeruli involved by segmental scarring was 3.41±2.87 and there was significant difference among the variants (p= 0.001). Arteriolopathy was found in 23.4 % cases and fibrointimal thickening of arteries in 18.5%. Tubular atrophy and interstitial fibrosis (IF/TA) was noted in 93% of cases. There was no significant difference in vasculopathy and IF/TA among the variants.

CONCLUSIONS

Collapsing variant was the second most common variant following NOS and these findings are different from other regional studies.