Extrarenal Tumor Research Articles

Percutaneous Thermal Ablation for Managing Small Renal Metastatic Tumors.

To retrospectively evaluate the treatment outcomes of thermal ablation for renal metastatic tumors. Thirteen consecutive patients with small renal metastatic tumors (≤3 cm), who underwent thermal ablation between 2009 and 2020, were included in this study. Eight patients had extra-renal tumors during renal ablation. The primary tumors were adenoid cystic carcinoma in four patients, lung cancer in three, hemangiopericytoma in three, leiomyosarcoma in two, and thyroid cancer in one. The therapeutic effects, safety, survival rate, prognostic factor, and renal function were evaluated. We performed 18 ablation sessions (cryoablation, n = 13; radiofrequency ablation, n = 5) on 19 renal metastases with a mean diameter of 1.7 cm, which resulted in a primary technique efficacy rate of 100% without procedure-related deaths or major complications. Renal function significantly declined 6 months after ablation (P = 0.0039). During the mean follow-up period of 31.2 ± 22.4 months (range, 2.7-71.4 months), one patient had local tumor progression at 11.9 months following radiofrequency ablation. The overall survival rates at 1 and 3 years after ablation were 76.9% (95% confidence interval [CI], 54.0%-99.8%) and 59.3% (95% CI, 31.3%-87.3%), respectively. Tumor size ≥ 2 cm (P = 0.02) and metastasis from non-small cell lung cancer (P = 0.001) were significant worse prognostic factors in univariate analysis, and metastasis from non-small cell lung cancer (P = 0.01) was significant in multivariate analysis. Percutaneous thermal ablation for small renal metastases is safe and feasible and can control local tumors.

Tyrosine kinase-altered spindle cell neoplasms with EGFR internal tandem duplications.

In this study, we present two extra-renal pediatric spindle cell neoplasms with epidermal growth factor receptor (EGFR) internal tandem duplications (ITD). Histologically, these tumors demonstrated the same histologic features seen in other tyrosine kinase-altered spindle cell neoplasms, with one case showing abundant adipose tissue with cellular fibrous septae resembling lipofibromatosis and the other case showing fascicles of spindled cells resembling infantile fibrosarcoma. There was variable expression of CD34, S100, and SMA, and all cases were negative for panTRK. This case series adds to our molecular understanding of the spectrum of tyrosine kinase-altered spindle cell neoplasms and represents the first reported examples of EGFR ITDs in extra-renal tumors. The presence of EGFR alterations in the absence of gene fusions represents a potential therapeutic target and necessitates a broader testing panel for this group of tumors.

Predictors of postoperative recurrence in patients with non-metastatic pT3a renal cell carcinoma.

To analyze the effect of patterns of extrarenal tumor extension with other pathological factors on postoperative recurrence in patients with non-metastatic pT3a renal cell carcinoma. We retrospectively reviewed 587 non-metastatic renal cell carcinoma patients who underwent radical surgery between 2006 and 2017 at Kansai Medical University Hospital, Hirakata, Osaka, Japan. We extracted a subset of 114 patients with pT3a of predominant histological types: 93 with clear cell renal cell carcinoma (81.6%), 13 with unclassified renal cell carcinoma (11.4%), six with chromophobe renal cell carcinoma (5.3%) and two with papillary renal cell carcinoma. The primary end-point was recurrence-free survival. The Kaplan-Meier method and Cox proportional hazards model were used for statistical analysis. Of the 114 patients with pT3a renal cell carcinoma, 42 patients (36.8%) experienced recurrence. Multivariate analysis showed that perinephric fat invasion (hazard ratio 2.36, P=0.009), sarcomatoid or rhabdoid component (hazard ratio 2.88, P=0.022) and necrosis (hazard ratio 2.34, P=0.030) were independent factors for recurrence-free survival. The high-risk pT3a group, which had more than two independent predictors, had poor prognosis. Recurrence-free survival of the high-risk pT3a group and the pT3b or greater group were similar (median recurrence-free survival 23.0 and 10.8months, respectively). Perinephric fat invasion, sarcomatoid or rhabdoid component and necrosis are independent predictors of recurrence-free survival in patients with pT3a-predominant renal cell carcinoma. Patients with more than two of these predictors have poor oncological outcomes. These findings will aid in risk stratification for predicting recurrence and provide prognostic information for patient counseling.

Imaging evaluation of hereditary renal tumors: a pictorial review.

More than 10 hereditary renal tumor syndromes (HRTSs) and related germline mutations have been reported with HRTS-associated renal and extrarenal manifestations with benign and malignant tumors. Radiologists play an important role in detecting solitary or multiple renal masses with or without extrarenal findings on imaging and may raise the possibility of an inherited predisposition to renal cell carcinoma, providing direction for further screening, intervention and surveillance of the patients and their close family members before the development of potentially lethal renal and extrarenal tumors. Renal cell carcinomas (RCCs) associated with von Hippel-Lindau disease are typically slow growing while RCCs associated with HRTSs, such as hereditary leiomyomatosis and renal cell carcinoma syndrome, are highly aggressive. Therefore, radiologists need to be familiar with clinical and imaging findings of renal and extrarenal manifestations of HRTSs. This article reviews clinical and imaging findings for the evaluation of patients with well-established HRTSs from a radiologist's perspective to facilitate the clinical decision-making process for patient management.

Clinical and genetic risk factors define two risk groups of extracranial malignant rhabdoid tumours (eMRT/RTK).

Extracranial rhabdoid tumours are rare, highly aggressive malignancies primarily affecting young children. The EU-RHAB registry was initiated in 2009 to prospectively collect data of rhabdoid tumour patients treated according to the EU-RHAB therapeutic framework. We evaluated 100 patients recruited within EU-RHAB (2009-2018). Tumours and matching blood samples were examined for SMARCB1 mutations by sequencing and cytogenetics. A total of 70 patients presented with extracranial, extrarenal tumours (eMRT) and 30 with renal rhabdoid tumours (RTK). Nine patients demonstrated synchronous tumours. Distant metastases at diagnosis (M+) were present in 35% (35/100), localised disease (M0) with(LN+) and without (LN-) loco-regional lymph node involvement in 65% (65/100). SMARCB1 germline mutations (GLM) were detected in 21% (17/81 evaluable) of patients. The 5-year overallsurvival (OS) and event-free survival (EFS) rates were 45.8±5.4% and 35.2±5.1%, respectively. On univariate analyses, age at diagnosis (≥12 months), M0-stage, absence of synchronous tumours, absence of a GLM, gross total resection (GTR), radiotherapy and achieving a CR were significantly associated with favourable outcomes. In an adjusted multivariate model presence of a GLM, M+ and lack of a GTR were the strongest significant negative predictors of outcome. We suggest to stratify patients with localised disease (M0), GTR+ and without proof of a GLM (5-year OS 72.2±9.9%) as 'standard risk'. Patients presenting with one of the features M+ and/or GTR- and/or GLM+ belong to a high risk group (5-year, OS 32.5±6.2%). These patients need novel therapeutic strategies such as combinations of targeted agents with conventional chemotherapy or novel experimental approaches ideally within international phase I/II trials.

Laparoscopic thulium fiber laser partial nephrectomy without thermal ischemia

Background. Laparoscopic partial nephrectomy (LPN) in the treatment of small kidney tumors is widespread, but the operation is associated with warm ischemia, which adversely affects the functional state of the kidney. Research is underway on methods of partial nephrectomy with a reduction of thermal ischemia or zero ischemia. The laser energy is one of the directions in the search for options for LPN. The aim of our work is to improve the LPN using a thulium laser. Materials and methods. From 2017 to 2019 a LPN was performed for 16 patients with small tumors, using the thulium laser with a wavelength of 1.94 ^m. There were men 7 (43.8 %), women — 9 (56.2 %), average age was 51 (39—68) years, average kidney tumor size was 24.9 (15—40) mm. The evaluation of laser resectability on the RENAL scale was carried out using 3D modeling. We used the laparoscopic laser aspirator-irrigator to reduce smoke generation during the procedures. Results. The average time of LPN using a fiber thulium laser was 97.5 (70—131) min. The time for kidney resection was 25.6 (10—40) min. 14 (87.5 %) procedures performed completely without warm ischemia. The average blood loss during surgery was 111.3 (50—250) ml. The duration of postoperative treatment was 7.1 (5—9) days. A positive surgical margin was not observed. Histological examination revealed renal cell carcinoma in 14 (87.5 %) patients, G2 — 10 (71.4 %), G2 — 4 (28.6 %). When examining glomerular filtratoin rare in the operated patients after procedures, no changes were observed. Conclusion. The use of the thulium laser for LPN allows perform the procedure without warm ischemia in selected patients with a predominantly extrarenal tumor location. The use of a laparoscopic instrument the laser aspirator-irrigator with a drip water supply and simultaneous aspiration reduced smoke generation during laser thulium resection, the operation performed under conditions of improved visualization, which prevents the danger of a positive surgical edge. Further monitoring of the results of applying the method of thulium laser LPN is required.

Re-evaluation of Pt staging categories for renal cell carcinoma

Staging of renal cell carcinoma has evolved since the initial classification of Flocks and Kadesky in 1958. Currently most cancer registries utilise the UICC or AJCC classifications, now both in their eighth editions. These classifications assign localised tumours to pT1-2 categories, with the two subdivisions being based on tumour size. pT3 tumours show regional infiltration, with renal sinus invasion (pT3a) being most frequently seen. This study was undertaken to determine the association between extrarenal tumour spread and size in a series of well-sampled clear cell renal cell carcinoma (ccRCC). In a series of 917 cases of ccRCC, 178 were >7 cm in maximum extent. Assessment of tumours >7 cm in size showed 72 (40.4%) to have renal sinus infiltration, the tumour infiltrating perirenal fat in 7 (3.9%) cases, and both in 96 (53.9%) cases. In the remaining 3 (1.7%) cases, no extrarenal extension of the tumour was seen. These 3 cases with organ-confined ccRCC were all cystic tumours. For tumours ≤7 cm in maximum extent there was an increase in the proportion of tumours showing extrarenal spread with increasing size. These findings indicate that the defining features of pT1, pT2, and pT3a staging categories for ccRCC require revision.

Evaluation of individual and cumulative sites of extrarenal tumor invasion in pT3a clear cell renal cell carcinoma

IntroductionThe Tumor-Node-Metastasis classification of renal cell carcinoma (RCC) for pT3a tumors includes sinus fat invasion (SFI), perinephric fat invasion (PFI), renal vein invasion (RVI), and/or pelvicaliceal system invasion (PSI). The purpose of this study was to determine the association between these patterns of invasion (assessed individually and cumulatively) with the development of metastases and cancer-specific mortality (CSM). Materials and methodsWe identified 160 patients who underwent radical nephrectomy for pT3a clear cell RCC between 2011 and 2017. The association between individual patterns of invasion and metastases and cancer-specific survival were evaluated with multivariate logistic regression. Cox Hazard proportion ratios and Kaplan-Meier survival curves were generated for patterns of invasion (assessed individually and cumulatively). ResultsThe number of individual invasive patterns was as follows: 97/160 (61%) presented with RVI, 91/160 with SFI (57%), 62/160 with PFI (39%), and 24/160 (15%) with PSI. At multivariate analysis, both PFI and RVI were associated with metastases (P < 0.001 and 0.028, respectively). PFI (hazard ratio [HR] 4.12, 95% confidence interval [CI] 2.14–7.92; P < 0.001), RVI (HR 2.44, 95% CI 1.18–5.01; P = 0.015), SFI (HR 2.13, 95% CI 1.05–4.34; P = 0.036) had higher CSM, while PSI (HR 1.43, 95% CI 0.65-3.16; p = 0.38) did not show increased CSM. Furthermore, cumulative analysis showed that multiple invasive patterns resulted in worse CSM (p < 0.001). ConclusionsIn our study, PFI was associated with the most aggressive behavior while PSI was the most indolent. Furthermore, the presence of more than one pattern of invasion was associated with worse CSM. These results indicate that reporting of the individual location and cumulative amount of pT3a patterns of invasion in clear cell RCC is clinically relevant.

Is the UICC/AJCC pT2 Staging Category for Clear Cell Renal Cell Carcinoma Meaningful?

This study was undertaken to determine the association between extrarenal tumor spread and size in a series of well-sampled clear cell renal cell carcinoma (ccRCC). In a series of 917 cases of ccRCC, 178 were >7 cm in maximum extent. Assessment of tumors >7 cm in size showed 72 (40.4%) to have renal sinus infiltration, the tumor infiltrating perirenal fat in 7 (3.9%) cases, and both in 96 (53.9%) cases. In the remaining 3 (1.7%) cases, no extrarenal extension of the tumor was seen. These 3 cases with organ-confined ccRCC were all cystic tumors. Two showed extensive infarction with associated hemorrhage and the presence of a thick investing pseudocapsule, while the third was a cystic ccRCC arising in the upper pole of the kidney. For the ccRCCs in the series that were ≤7 cm in maximum extent, division of cases according to tumor size and pT staging category showed an increase in the proportion of tumors showing extrarenal spread with increasing size, ranging from 0% for tumors <1 cm in diameter to 84.7% for tumors >6 to 7 cm. The study has shown that for ccRCC, the extrarenal spread of tumor is strongly associated with the size of the primary tumor. The study has also shown that renal sinus invasion and/or perirenal fat infiltration by tumor is commonplace in tumors >7 cm in maximum extent and that tumors of this dimension are rarely organ-confined. These findings provide evidence that the defining features of pT1, pT2, and pT3a staging categories for ccRCC require revision.

Chromophobe Renal Cell Carcinoma With High-Grade Features

Chromophobe renal cell carcinoma (ChRCC) generally has a favorable behavior; however, a small subset of these tumors behaves aggressively. Grading of ChRCC has been challenging. Studies have shown that the traditional Fuhrman nuclear grade (FNG), or any of its components, is not useful as a prognostic indicator for ChRCC. Recently, the International Society of Urological Pathology (ISUP) recommended a novel grading (ISUP grade) for renal cell carcinoma (RCC) that relies mainly on nucleolar prominence, a component of FNG, and is applicable at least for clear cell RCC and papillary RCC. The ISUP also recommended that ChRCC should not be graded. Several other grading schemes have been studied in ChRCC, notably the recently introduced chromophobe tumor grade (CTG), which discounts the constitutive nuclear atypia in ChRCC. Studies have shown that CTG provides a superior prognostic value than FNG, and CTG is suggested by some authors as the preferred grading scheme for ChRCC. However, limited data suggest that CTG and stage are perhaps intercorrelated, and although CTG is associated with the outcome of ChRCC, its prognostic value may be diminished when pathologic stage is assessed. So far, validation studies regarding CTG were hampered by having few adverse events in the analyses because of the generally favorable outcome and the uncommon incidence of ChRCC. An evolving question is whether grading can be useful in needle core biopsy specimens with ChRCC, as conservative management such as active surveillance is being introduced and where clinical staging of extrarenal tumor extension (≥pT3) by imaging may not be accurate. Future definitive studies require larger multi-institutional accrual of ChRCCs to provide a better understanding of the prognostic value of grading ChRCC.

Extrarenal Nephroblastoma

Introduction: As much as the nephroblastoma is almost exclusively known to be a renal tumor, some of the extrarenal locations, although rare, have been described in the literature. The sites of this rare entity (extrarenal nephroblastoma) reported entail the inguinal canals, retro-peritoneum, mediastinum, chest wall, ovaries, cervix, uterus and the prostate gland. Case Report: We report a case of a 13-month-old boy who was referred from the peripheral hospital presenting with severe abdominal distention of three months duration. The patient was critical ill on arrival and had to be actively resuscitated. The patient was emaciated. No known past medical history reported and the patient had normal developmental milestones. On physical examination a large abdominopelvic mass was palpated. The patient also had sepsis confirmed with blood culture and hypoglycemia with a blood glucose measurement of 1.4 mmol/l saturation was 96% in room air and had episodes of gasping respiration, the heart beat was ranging between 110–140 bpm. The patient had pallor with hemoglobin 8.4 g/dL and had cold peripheries. Computed tomography scan and biopsy were performed and the diagnosis of an extrarenal large abdominopelvic nephroblastoma was made. The patient was later, after stabilization, treated with chemotherapy. The patient now remains in a critical general condition while on chemotherapy. Conclusion: A nephroblastoma may present in some extrarenal sites which is quite an uncommon encounter, the most common of these rare sites being the retro-peritoneum. The final diagnosis is mainly histopathological. There are no specific management protocols and as a result the extrarenal tumors are managed in the same manner in which the intra-renal tumors are managed with a general good prognosis.

Renal-type clear cell carcinoma of the prostate: A case report.

Renal-type clear cell carcinoma of the prostate is a rare and novel tumor that has only been identified in recent years. The present study describes a lesion in the prostate of a 64-year-old male with a two-year history of urinary frequency, urgency and difficulty, who was admitted to the San Ai Tang Hospital for benign prostatic hyperplasia, and subsequently underwent transurethral resection of the prostate. In total, 12 g of tissue was resected, which demonstrated morphological and immunohistochemical similarities to clear cell carcinoma of the kidney. Ultrasound inspection and computed tomography revealed prostate enlargement. Although no renal-enclosed mass was identified, metastatic lesions were revealed in the lungs, sternum and clavicles. In addition, right pleural thickening and a small amount of effusion in the pleural cavity were detected. Clear cell carcinoma was identified throughout the prostate, with surrounding regions of ordinary-type prostatic adenocarcinoma (Gleason score, 4+4). The urinary bladder exhibited no dysplasia or neoplasia. It was therefore concluded that the tumor represented a primary renal-type clear cell carcinoma that had arisen in the prostate. To the best of our knowledge, this type of extra-renal tumor has only been reported in three other previous studies.

Extrarenal Wilms' Tumor With Intraspinal Extension : A Case Report

This report illustrates a proven rare case of retroperitoneal extrarenal Wilms’ tumor, and discusses the radiological features of this tumor, for a 19 month old female patient referred to our radiology department with an abdominal mass for further evaluation. Abdominal Ultrasound, Computed Tomography and abdominal Magnetic Resonance Imaging were performed and showed right upper quadrant abdominal mass, displaying right kidney upward and extended to the spinal canal at that level. The case was discussed thoroughly. Our preliminary diagnosis was in favor of neurogenic tumor and neuroblastoma was on the top of our differential diagnosis. Histopathological examination of the surgically excised tumor confirmed the diagnosis of extrarenal Wilms' tumor. Postoperative adjuvant chemotherapy was performed. During the following 24 months, no local recurrence or distant metastasis were detected.

Renal vein leiomyosarcoma: imaging and clinical features of a renal cell carcinoma mimic

Renal vein leiomyosarcoma is a rare tumor whose clinical and imaging features can significantly overlap with those of advanced primary renal neoplasms, particularly renal cell carcinoma. IRB approval was obtained for a retrospective review of clinical and imaging information for five patients with the pathologically proven diagnosis of renal vein leiomyosarcoma at two institutions. Among the five patients, two were female and three male; average age 58.6 (range 42-77). Three patients presented with flank or abdominal pain, one with pulmonary embolism, and one with weight loss and fatigue. Mass size ranged from 4 to 10cm. Four masses were left-sided and one right-sided. Tumors involved and expanded the renal vein in all cases, with tumor extension to the renal hilum in one case, through the renal hilum into renal parenchyma in two cases, and into inferior vena cava in two cases. All masses demonstrated contrast enhancement, which was solely peripheral in one case. In all cases, extrarenal tumor volume was greater than renal parenchymal tumor volume. When renal masses are predominantly or exclusively intravascular, consideration should be given to the diagnosis of renal vein leiomyosarcoma because preoperative biopsy results could significantly alter management.

990 PARTIAL NEPHRECTOMY VERSUS RADIAL NEPHRECTOMY FOR T1B RENAL CELL CARCINOMA: ONCOLOGICAL AND FUNCTIONAL OUTCOMES

You have accessJournal of UrologyKidney Cancer: Localized II1 Apr 2010990 PARTIAL NEPHRECTOMY VERSUS RADIAL NEPHRECTOMY FOR T1B RENAL CELL CARCINOMA: ONCOLOGICAL AND FUNCTIONAL OUTCOMES Sangjun Yoo, Taejin Kang, Cheryn Song, Jun Hyuk Hong, Choung-Soo Kim, and Hanjong Ahn Sangjun YooSangjun Yoo More articles by this author , Taejin KangTaejin Kang More articles by this author , Cheryn SongCheryn Song More articles by this author , Jun Hyuk HongJun Hyuk Hong More articles by this author , Choung-Soo KimChoung-Soo Kim More articles by this author , and Hanjong AhnHanjong Ahn More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.1959AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES To compare the oncological and functional outcomes of radical nephrectomy (RN) and partial nephrectomy (PN) for T1b renal cell carcinoma. METHODS We identified 27 patients who underwent PN for T1b renal cell carcinoma at Asan Medical Center between Jan 1991 and Dec 2007. Each case was matched with 2 patients with identical demographic, clinical and pathological characteristics who underwent RN during the same period. Recurrence-free and cancer specific survival, glomerular filtration rate (GFR) calculated by modification of diet in renal disease equation and chronic kidney disease (CKD) status were compared between the PN and RN group. All cases were done electively and there were no patients with single kidney in both groups. RESULTS Mean tumor size was 5 cm in both groups but extra-renal tumor diameter/total tumor diameter ratio was higher in the PN group (PN, 56.7%; RN, 38.1%, p=0.001). PN group had longer renal sinus-tumor length than RN group (PN, 0.54cm; RN, 0.22cm, p=0.017). In RN group, one local recurrence was observed and no cancer-specific death occurred during a mean follow up of 45 months. In PN group, there was no local recurrence or cancer-specific death during a mean follow up of 48 months demonstrating equivalent oncological outcome to RN group. Number of patients with hypertension or diabetes preoperatively was 7 and 11 in PN and RN groups, respectively. Incidence of CKD was 1 in both groups (3.7% and 1.9%). Pre-operative GFR of PN group was 88.4ml/min/1.73min2 and of RN group was 93.0ml/min/1.73min2 (p=0.298). At postoperative 1 year, 2 years, and 3 years GFR changed to 82.8ml/min/1.73min2, 80.6ml/min/1.73min2, and 80.9ml/min/1.73min2 in PN group and 62.3ml/min/1.73min2, 64.2ml/min/1.73min2, 66.6ml/min/1.73min2 in RN group (PN vs. RN; preop. vs. postop., all p<0.05). Postoperative CKD developed in 1 patient in PN group (3.8%, 1/26) whereas 18(34.0%, 18/53) patients demonstrated CKD in the RN group. CONCLUSIONS In T1b renal cell carcinoma, PN exhibited comparable oncological outcome and superior renal function preservation compared to RN. In technically amenable cases, PN can be safely considered as a primary option. SEOUL, Republic of Korea© 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e385 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sangjun Yoo More articles by this author Taejin Kang More articles by this author Cheryn Song More articles by this author Jun Hyuk Hong More articles by this author Choung-Soo Kim More articles by this author Hanjong Ahn More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Invasion of renal sinus fat is not an independent predictor of survival in pT3a renal cell carcinoma

To clarify the significance of the location of extrarenal tumour extension of renal cell carcinoma (RCC) as in the 2002 Tumour-Nodes-Metastasis classification. Renal cortical tumours with perirenal fat invasion (PFI) or sinus fat invasion (SFI) are consolidated within the pT3a grouping; tumours with SFI are close to the renal veins, lymphatics and the collecting system. This might carry a worse prognosis for disease-specific survival (DSS), but reports are limited and contradictory. We retrospectively reviewed 1244 patients treated with nephrectomy from 1988 to 2007, to identify patients with pT3a renal tumours. They were classified as having PFI or SFI. Kaplan-Meier analysis and Cox proportional hazards regression models were used to assess predictors of survival. The 230 patients who met the inclusion criteria had a median follow-up of 24 months. SFI was found in 63 (27.4%) patients and was associated with a worse 5-year DSS than the 167 (72.6%) with PFI (62.5% vs 75.0%; log rank P = 0.022). On univariate analysis, diameter (hazard ratio, HR 1.1), nuclear grade (HR 4.5), margin status (HR 5.8), lymph node metastases (HR 6.4), and systemic metastases (HR 15.4) were significant for DSS. In a multivariate model, only nuclear grade (HR 3.1), margin status (HR 8.9) and systemic metastases (HR 9.8) were independent predictors. Patients with renal tumours with SFI are more likely to die from RCC than those with PFI. However, in the present patients the presence of SFI was not an independent predictor of DSS.

Extrarenal rhabdoid tumours outside the central nervous system in infancy

Malignant rhabdoid tumours (RT) are increasingly recognized in young children, probably as a consequence of advances in accurate histological diagnosis rather than a true increase in frequency. Although typically presenting as renal tumours in infancy, extrarenal tumours outside the central nervous system (CNS) in children less than 12 months of age are now well recognized, but previous literature on their imaging features is very limited. To demonstrate the imaging features of extrarenal RTs outside the CNS. A retrospective database review was made from 1989 to 2007 of patients diagnosed with extrarenal RT in infancy, i.e. below 12 months of age. There were nine patients (six boys and three girls). The age at presentation varied from 1 to 11 months (average 6 months). Tumours were located in the thorax/mediastinum (n=3), liver (n=3), neck (n=1), shoulder (n=1) and axilla (n=1). The imaging modalities used included US (n=8), CT (n=7) and MRI (n=6). Bone scan was positive in one patient, while metastases at the time of diagnosis occurred in four patients. On MRI the tumours tended to show nonspecific hypointensity on T1-W images and heterogeneous hyperintensity on T2-W images, with heterogeneous enhancement. This is the largest radiological series of extrarenal RTs outside the CNS in infancy. In our series no imaging features were found specific to the diagnosis. A tendency towards large size and mediastinal/paravertebral location were noted. A hypodense solid component on CT and a heterogeneous hyperintensity on T2-W MR images suggest that this tumour should be considered in the routine differential diagnosis of soft-tissue tumours in infancy, in addition to rhabdomyosarcoma.

Monotypic epithelioid angiomyolipoma of the adrenal gland: an unusual site for a rare extrarenal tumor

Epithelioid angiomyolipoma (AML) is an uncommon renal mesenchymal tumor with malignant potential and is frequently associated with tuberous sclerosis. Extrarenal AMLs are rare, and to the best of our knowledge, this is the first reported case of a primary monotypic epithelioid AML of adrenal gland in a patient without evidence of tuberous sclerosis. The patient is a 42-year old man who presented with retroperitoneal hemorrhage resulting from spontaneous rupture of adrenal mass. Histologically, the tumor showed a prominent component of epithelioid smooth muscle cells with slightly pleomorphic nuclei, sometimes with prominent nucleoli and eosinophilic cytoplasm resembling oncocytic tumors. Epithelioid cells were positive for melanoma (HMB45 and positive MelanA) and smooth muscle markers (alpha-smooth muscle-specific actin), but not for epithelial markers (cytokeratin, EMA). Differential diagnosis from renal cell carcinoma, adrenal gland carcinoma, and metastatic carcinoma is often challenging because of its epithelioid morphology. Because primary and secondary malignant tumors are much more common and aggressive neoplasms, establishing the correct diagnosis has important therapeutic and prognostic implications.

LUMBOSACRAL WILMS' TUMOR AS A COMPONENT OF IMMATURE TERATOMA ASSOCIATED WITH SPINAL DYSRAPHISM—A RARE CASE AND SHORT LITERATURE REVIEW

Occurrence of extrarenal Wilms' tumor, in the lumbosacral region, as such or as a component of immature teratoma is an extremely uncommon condition and this diagnosis is almost always postsurgical. We report a case of immature teratoma in the lumbosacral region which was composed of mature teratomatous components and Wilms' tumor as an immature component. This 20-day-old male child presented with a swelling over the lower back at birth. Imaging of the spine revealed spina bifida and tethered cord. Excision of soft tissue swelling and detethering of the cord was performed. This case represents the fourth reported case of lumbosacral Wilms' tumor as a component of immature teratoma associated with spinal dysraphism. We discuss possible mechanisms and clinical characteristics of extrarenal Wilms' tumor and present a short review of the literature.

A Case of Malignant Rhabdoid Tumor in the Anterior Mediastinum

Malignant rhabdoid tumors arise primarily from the kidney. Extrarenal malignant rhabdoid tumors are rare, with the liver, central nervous system, and skin reported as the primary sites. Malignant rhabdoid tumors of the mediastinum are extremely rare among extrarenal malignant rhadoid tumors; only 3 cases have been reported to date, all characterized by aggressive clinical behavior. We experienced a 35-year-old woman diagnosed with malignant rhabdoid tumor in the anterior mediastinum with multiple metastases. The tumor was surgically unresectable, and treated with palliative radiation therapy. Three-month after radiation treatment, she died from dissemination of the malignant rabdoid tumor.