Ectopic adrenal tissue in the kidney: A systematic review

Introduction: Ectopic adrenal tissue in the kidney, including “Ectopic adrenal tissue” and “Adrenal-renal fusion”, is a rare event with a specific behavior which may be difficult to distinguish clinically from renal neoplasms. We performed a systematic review on ectopic adrenal tissue variants reported in the literature underlining its clinical aspects. Methods: Manuscripts which presented a case report or case series of ectopic adrenal tissue in the kidney were included even if published in original articles, reviews, or letters to the editor. A specific search on SCOPUS®, PubMed®, and Web of Science® database was performed. Only English language papers published in a period ranging between August 1991 and April 2020 were considered. Additionally, a case we had at our institution is described, and its characteristics are included. Data on clinical presentation, type of adrenal anomaly, location, anatomopathological and immune-histotype characteristics were collected. Results: We identified 888 manuscripts. Among these 29 were included in this systematic review. Overall, 39 patients with renal adrenal fusion or adrenal ectopia were considered. In most cases, the diagnosis was made incidentally, or following investigation for flank pain, abdominal pain, or endocrinological disorders. CT scan frequently identified a solid vascularized lesion that was difficult to distinguish from renal neoplasm. Adrenal fusion was mostly located at the level of the upper pole. Adrenal rest was found in the renal parenchyma, renal hilum, or retroperitoneum in close proximity to the renal peduncle. Often these ectopic adrenal tissue lesions follow a benign behavior and can be classified as functioning or non-functioning adenomas. Rarely, they may experience neoplastic degeneration. The most frequently positive markers were inhibin, vimentin, melan-A, synaptophysin and anti-p450 scc. Conclusions: Ectopic adrenal tissue in the kidney is a rare event with specific clinical characteristics that need to be identified in order to arrive at a correct diagnosis and carry out appropriate treatment management.

Comparison of Survival Between Unilocular Cystic and Purely Solid Renal Cell Carcinoma

Purpose To evaluate clinicopathologic features and survival outcomes of unilocular cystic renal cell carcinoma (cRCC) compared with purely solid renal cell carcinoma (RCC), and to evaluate the oncologic aggressiveness of unilocular cRCC. Methods The relevant data of 957 patients with sporadic unilateral RCCs underwent surgical treatment in 2 institutions from Jan 2014 to Oct 2018 were obtained. We excluded multilocular cystic renal neoplasm of low malignant potential (MCRNLMP), RCCs with multilocular cysts and necrotic RCCs. 74 unilocular cRCCs were identified by pathology reports. We performed propensity score matching (PSM) and randomly selected 148 purely solid RCCs. The clinicopathologic features and survival outcomes were compared properly. Results After PSM, age, BMI, Charlson Comorbidity Index, and postoperative Chronic Kidney Disease grade were not significantly different. Both overall survival and cancer-specific survival of unilocular cRCCs were significantly better than the purely solid RCCs by the log-rank test. Twenty-five cases of solid RCCs were in the pT3 or pT4 stage, while no pT3 or pT4 tumors were found in unilocular cRCCs. Fuhrman grade, pT stage, lymphatic metastasis and tumor diameter were found to be independent prognostic factors. Conclusion Unilocular cRCCs have a lower Fuhrman grade and pathological stage and a better prognosis compared with solid RCC. Unilocular cRCCs still probably have lymphatic metastasis at diagnosis and may have postoperative metastasis, which is different from MCRNLMP. We recommend that the diagnosis of unilocular cRCC should be reflected in pathology reports. Different subtypes of cRCC should be taken into consideration in counseling and management.

The Morphological Spectrum of Papillary Renal Cell Carcinoma and Prevalence of Provisional/Emerging Renal Tumor Entities with Papillary Growth

Renal cell carcinoma (RCC) represents a heterogeneous disease, encompassing an increasing number of tumor subtypes. Post-2016, the World Health Organization (WHO) classification recognized that the spectrum of papillary renal cell carcinoma is evolving and has long surpassed the dichotomic simplistic “type 1 versus type 2” classification. The differential diagnosis of pRCC includes several new provisional/emerging entities with papillary growth. Type 2 tumors have been cleared out of several confounding entities, now regarded as independent tumors with specific clinical and molecular backgrounds. In this work we describe the prevalence and characteristics of emerging papillary tumor entities in two renal tumor cohorts (one consisting of consecutive papillary tumors from a single institute, the other consisting of consultation cases from several centers). After a review of 154 consecutive pRCC cases, 58% remained type 1 pRCC, and 34% type 2 pRCC. Papillary renal neoplasm with reversed polarity (1.3%), biphasic hyalinizing psammomatous RCC (1.3%), and biphasic squamoid/alveolar RCC (4.5%) were rare. Among 281 consultation cases, 121 (43%) tumors had a dominant papillary growth (most frequently MiT family translocation RCCs, mucinous tubular and spindle cell carcinoma and clear cell papillary RCC). Our data confirm that the spectrum of RCCs with papillary growth represents a major diagnostical challenge, frequently requiring a second expert opinion. Papillary renal neoplasm with reversed polarity, biphasic hyalinizing psammomatous RCC, and biphasic squamoid/alveolar RCC are rarely sent out for a second opinion, but correct classification and knowledge of these variants will improve our understanding of the clinical behavior of renal tumors with papillary growth.

Heterotopic Ossification in Benign and Malignant Renal Neoplasms

Introduction/Objective Heterotopic bone formation in renal neoplasms is a rare phenomenon. Ossification with or without marrow elements has been reported in both benign and malignant renal tumors. Due to its rarity, the epidemiological and clinical features of this finding are not well-documented. Herein, we have examined heterotopic ossification in renal neoplasms and summarized the epidemiological and clinical features of this entity. Methods/Case Report A database search on PubMed, Scopus, and Google Scholar was performed using a combination of proper search terms. Full article texts of all search results were reviewed with reference lists screened for additional articles matching the search criteria. The demographic details of the patients, disease characteristics, treatment, and outcomes were all extracted from full text articles and were summarized in a pre-standardized form. The inclusion criteria were set as any epithelial renal neoplasm with histological evidence of heterotopic ossification. A case of clear cell renal cell carcinoma (CCRCC) with heterotopic ossification diagnosed in our institution is included in the study. Results (if a Case Study enter NA) A total of 30 cases were found of renal neoplasms with bone formation. The majority of patients were between the ages of 40 to 60. The male to female ratio was 1:1. The majority (19/30) were histologically diagnosed as CCRCC, the most common subtype of kidney tumor with a few cases diagnosed as chromophobe RCC (4/30), papillary RCC (3/30), and cystic nephroma (2/30). Of the neoplasms reported, tumor size varied from 3.0 cm to 28.8 cm. Conclusion Heterotopic ossification of renal neoplasms often presents a diagnostic challenge to the radiologist as other benign conditions such as extramedullary hematopoiesis can be in the differential. The rarity of this phenomenon renders pre-surgical diagnosis difficult. Our study documents this phenomenon to be seen in a variety of renal neoplasms and underscores the necessity to be aware of this rare entity.

Primary squamous cell carcinoma of renal pelvis and kidney- Sole diagnosis by histopathology

Primary Squamous cell carcinoma of the renal pelvis is rare and accounts to only 0.5- 0.8 % of malignant renal tumours having poor prognosis. Chronic irritation, inflammation and infection induce the pathogenesis of this malignancy. A 53 year old male patient, presented with left flank pain since one month. On radiological investigation, his CT revealed atrophic shrunken left kidney measuring 7.9x5.2cms showing significant parenchymal thinning and complete loss of corticomedullary differentiation. A left upper ureteric calculus is seen measuring 7.5 mm with significant left renal hydronephrosis.Clinically, it was diagnosed as Xanthogranulomatous Pyelonephritis. Grossly the radical nephrectomy specimen measures 10.5x5.5x3.5cm. External surface is irregular & bosselated. On Cut surface renal architecture is effaced by necrotic mass measuring 9.5x5.0x3.0 cm involving pelvic ureter and most of renal parenchyma.Hematoxylin and eosin stained tissue revealed characteristic feature such as keratin pearls and intracellular bridges seen, rendering the diagnosis of well-differentiated keratinising squmaous cell carcinoma seen with 40% tumour necrosis associated with Keratinizing Squamous Dysplasia. In the present case, obstructive uropathy has triggered the event of malignancy. The radiologic differential diagnosis includes primary and secondary renal neoplasms and xanthogranulomatous pyelonephritis associated with renal calculi. XGP is commonly associated with lithiasis however, rarely causes keratinizing squamous metaplasia and its manifestations closely mimic renal neoplasm, leading to misdiagnosis of malignancy.The prognosis is dismal with a 5-year survival rate of <10%. CT and MRI play a crucial role in diagnosis and staging of these tumors, though histology always remains confirmatory and diagnostic.

Absolute quantitative proteomics using the total protein approach to identify novel clinical immunohistochemical markers in renal neoplasms

Background Renal neoplasms encompass a variety of malignant and benign tumors, including many with shared characteristics. The diagnosis of these renal neoplasms remains challenging with currently available tools. In this work, we demonstrate the total protein approach (TPA) based on high-resolution mass spectrometry (MS) as a tool to improve the accuracy of renal neoplasm diagnosis. Methods Frozen tissue biopsies of human renal tissues [clear cell renal cell carcinoma (n = 7), papillary renal cell carcinoma (n = 5), chromophobe renal cell carcinoma (n = 5), and renal oncocytoma (n = 5)] were collected for proteome analysis. Normal adjacent renal tissue (NAT, n = 5) was used as a control. Proteins were extracted and digested using trypsin, and the digested proteomes were analyzed by label-free high-resolution MS (nanoLC-ESI-HR-MS/MS). Quantitative analysis was performed by comparison between protein abundances of tumors and NAT specimens, and the label-free and standard-free TPA was used to obtain absolute protein concentrations. Results A total of 205 differentially expressed proteins with the potential to distinguish the renal neoplasms were found. Of these proteins, a TPA-based panel of 24, including known and new biomarkers, was selected as the best candidates to differentiate the neoplasms. As proof of concept, the diagnostic potential of PLIN2, TUBB3, LAMP1, and HK1 was validated using semi-quantitative immunohistochemistry with a total of 128 samples assessed on tissue micro-arrays. Conclusions We demonstrate the utility of combining high-resolution MS and the TPA as potential new diagnostic tool in the pathology of renal neoplasms. A similar TPA approach may be implemented in any cancer study with solid biopsies.

Multilocular Cystic Neoplasm of Low Malignant Potential: A Rare and Incidental Finding of Clear Renal Cell Variant

Multilocular cystic renal neoplasm is a rare subtype of clear cell carcinoma with an incidence of 1-2 % of all clear cell carcinomas. Morphologically, it shows numerous cysts surrounded by fibrous capsule and septae containing clear cells. The aim of this case report is that the diagnosis is possible solely by histopathological and immunohistochemical evaluation, which aids in distinguishing it from other cystic clear cell entities, as imaging is inconclusive pre-opeartively. Urologists and radiologists should have an adequate understanding such an entity. Almost all the cases are amenable to partial nephrectomy irrespective of the size and there is no documentation regarding the recurrence and metastasis, which mandates less stringent follow up post – operatively compared to clear cell carcinoma.

Clinical Presentation and Treatment outcomes of Benign Renal Tumor: Angiomyolipoma

Background: Angiomyolipoma (AML) is a benign renal neoplasm composed of abnormal blood vessels, smooth muscle cells, and adipose tissue. About 40% of AMLs present with acute severe hemorrhage and is a potentially life-threatening condition. The risk of bleeding is proportional to tumor size and increasing significantly with size above 4 cm. Therefore, the patients with AMLs of 4 cm or more or spontaneous rupture of AMLs need interventional or surgical treatment. Objective: To evaluate the clinical presentation and treatment outcomes of the AMLs. Materials and Methods: The present report was a retrospective analytic study of the medical records and imaging studies in Phramongkutklao Hospital between January 2002 and December 2019. Results: Sixty-three patients, with a female:male ratio of 47:6, and a median age of 54.76 years with a range of 8 to 84 years, were included in the present analysis. Seven (11.1%) had tuberous sclerosis complex (TSC) and 56 (88.9%) had sporadic. Fifty-four had a solitary lesion, whereas nine had bilateral lesions. Asymptomatic AMLs were 50 (79.4%) and symptomatic AMLs were 13 (20.7%). There were 46 (73.0%) AMLs smaller than 4 cm and 17 (27.0%) AMLs of 4 cm or larger. AMLs smaller than 4 cm were incidentally discovered (n=40, 87%) and revealed due to symptoms such as flank pain (n=3, 6.5%) and hematuria (n=3, 6.5%). AMLs of 4 cm or larger were incidentally discovered (n=10, 58.8%) and revealed due to symptoms such as flank pain (n=7, 41.2%) and not presented with hematuria. AMLs smaller than 4 cm were mostly treated by follow up (n=39, 84.78%) or surgery (n=7, 15.22). AMLs of 4 cm or larger were treated by follow-up (n=11, 64.7%) then converted to arterial embolization (n=4, 23.5%) and converted to surgery (n=8, 47.1%). Two AMLs of 4 cm or larger died (11.8%). Conclusion: Significant differences in clinical manifestations and treatment outcomes were noted in respect to tumor characteristics, association with TSC, and treatment modality. Considering the benign nature of AML, size, and association with TSC ought to be considered when deciding upon active surveillance or prophylactic intervention. Keywords: Angiomyolipoma; Tuberous sclerosis complex; Embolization; Nephrectomy