Conservative treatment of renal angiomyolipomas in patients with tuberous sclerosis

Renal angiomyolipoma-patient characteristics and treatment with focus on active surveillance

Objectives: To present a patient material of renal angiomyolipoma (AML) with focus on the risk of bleeding during active surveillance (AS).Methods: Medical records, 1999-2014, were studied and 98 patients (80 female, 18 men) with renal AML were identified. Eleven patients had tuberous sclerosis complex (TSC). Mean age was 54 (13-89) years.Results: Sixty patients (61%) were asymptomatic at presentation, 33 (34%) presented with flank pain and five (5%) with hematuria. Retroperitoneal bleeding or hematuria was diagnosed in 20 patients with a mean AML size of 74 mm (25-200 mm). Twenty-one patients were treated with angioembolization at time of diagnosis and 25 had surgery. Forty-five patients with sporadic AML (mean size 34 mm) and six with TSC (mean size 120 mm) were selected for AS. Only one patient with sporadic AML (46 mm) had a bleeding, whereas two of the six TSC patients had bleedings from three kidneys (AML 70-300 mm). In 25 patients (49%), the AML-size increased with 2.7 mm/year in sporadic and 5.4 mm/year in TSC-associated AML. Thirteen patients were treated with AE (including all six TSC-patients) and five with surgery in 22 kidneys due to AML-size in 16, bleeding in four and suspicion of cancer in two.Conclusion: Bleeding occurred in 20% of AML at presentation. In patients selected for AS, we found a very low risk of bleeding in sporadic AML justifying our cut off size of 50 mm to trigger intervention. In TSC-associated AML individually tailored follow-up is needed due to a higher intervention rate.

Active surveillance for renal angiomyolipoma: outcomes and factors predictive of delayed intervention

OBJECTIVE

To present the outcomes of active surveillance (AS) for renal angiomyolipomas (AMLs) and to assess the clinical features predicting delayed intervention of this treatment option.

PATIENTS AND METHODS

We retrospectively reviewed the outcomes of patients diagnosed with AMLs on computed tomography (CT) who were managed with AS at our institution. The AS protocol consisted of 6- and 12-month, then annual follow-up visits, each one including a physical examination and CT imaging. Discontinuation of AS was defined as the need or decision for an active procedure during the follow-up period. Causes of delayed intervention, as well as the type of active treatment (AT), were recorded. Clinical features at presentation of patients failing AS were compared with those who remained under AS at the time of the last follow-up. Predictive factors of delayed intervention were analysed using univariate and multivariate Cox regression models.

RESULTS

Overall, 130 patients were included in the analysis, of whom 102 (78.5%) were incidentally diagnosed, while 15 (11.5%) and 13 patients (10%) presented with flank pain and haematuria, respectively. After a mean (sd) follow-up of 49 (40) months, 17 patients (13%) discontinued AS and underwent AT. Patients who underwent delayed intervention were more likely to present with a higher body mass index, larger tumours and symptomatic disease. Angioembolization represented the first-line AT after AS (64.7%), whereas partial nephrectomy was adopted in 29.4% of patients. On the univariate analysis, risk factors for delayed intervention included tumour size ≥4 cm, symptoms at diagnosis, and history of concomitant or contralateral kidney disease. On the multivariate analysis, only tumour size and symptoms remained independently associated with discontinuation of AS.

CONCLUSIONS

Tumour size and symptoms at initial presentation were highly predictive of discontinuation of AS in the management of AMLs. Selective angioembolization was the first-line option used for AT after AS was discontinued.

Renal angiomyolipomas in tuberous sclerosis--rare but potentially life-threatening lesions

We discuss an 18-year-old girl, diagnosed with tuberous sclerosis complex and known to have renal angiomyolipomas (AMLs) but having no regular urological follow-up, who presented with left-sided abdominal pain and haematuria on urine dipstick testing at the out-of-hours General Practitioner (GP) service. She was diagnosed as having urinary tract infection/pyelonephritis and discharged with simple analgesia and antibiotics. Subsequent imaging of her renal tract demonstrated multiple large AMLs with evidence of recent bleeding, which required arterial embolisation.

Epithelioid angiomyolipoma: a morphologically distinct variant that mimics a variety of intra-abdominal neoplasms

This review examines the histopathologic, immunohistochemical, ultrastructural, and molecular biologic features of epithelioid angiomyolipoma (EAML), with an emphasis on the differential diagnosis of intra-abdominal EAML. Epithelioid angiomyolipoma is an uncommon mesenchymal tumor with malignant potential, frequently associated with tuberous sclerosis complex. Histologically, EAML is characterized by sheets or nests of large polygonal epithelioid cells with abundant eosinophilic or occasionally clear cytoplasm, often with prominent nucleoli, and EAML may include multinucleated and markedly pleomorphic forms. As these tumors share a distinctive perivascular epithelioid cell phenotype, they belong to the PEComa tumor family. Nearly all EAMLs show immunoreactivity for both melanocytic and myoid markers. Ultrastructurally, EAMLs show evidence of melanogenesis by the presence of premelanosomes. Epithelioid angiomyolipoma can pose significant diagnostic challenges as it mimics morphologically a variety of neoplasms including renal cell carcinoma, renal oncocytoma, adrenal cortical neoplasm, epithelioid smooth muscle tumor, epithelioid peripheral nerve sheath tumor, epithelioid gastrointestinal stromal tumor, epithelioid melanoma, hepatoblastoma, and hepatocellular carcinoma. The variation in immunophenotype in these tumors requires a prudent use of immunohistochemistry, which may occasionally need complementation by electron microscopy to establish the correct diagnosis.

Trends of presentation and clinical outcome of treated renal angiomyolipoma

PURPOSE

The purpose of this study is to set guidelines for the management of renal angiomyolipoma (AML), clinical prognosis according to tumor size, in association with tuberous sclerosis complex (TSC), multiplicity, radiographic finding, and treatment modality.

MATERIALS AND METHODS

Between March 1998 and October 2008, 129 out of 254 patients with AML who underwent surgical intervention or angioembolization were enrolled. Diagnosis of AML was determined by the presence of a low attenuated component on CT imaging or by pathological confirmation. Indications of treatment were intractable pain, hematuria, suspicion of malignancy, large tumor size, spontaneous rupture, and radiographically equivocal tumors in which a differential diagnosis was needed to rule out malignancy. Parameters including age, sex, tumor size, multiplicity, radiographic characteristics, association with TSC, and treatment modality were reviewed.

RESULTS

Age at presentation was 50.6 years and mean tumor size was 3.5 cm. Presentation symptoms were flank pain, hematuria, spontaneous rupture, and fatigue. 97 (75.2%) patients were incidentally discovered. 100 (77.5%) were females. 68 (52.7%) underwent nephron-sparing surgery (NSS), 35 (27.1%) radical nephrectomy, and 26 (20.2%) angioembolization. TSC was accompanied in 12 (9.3%) patients. No patient developed renal function impairment during the mean follow-up period of 64.8 months. Patients with TSC presented at a younger age, along with larger, bilateral, and multiple lesions.

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, these parameters ought to be considered when deciding upon active surveillance or prophylactic intervention.

Transcatheter arterial embolization in patients with kidney diseases: an overview of the technical aspects and clinical indications

Therapeutic embolization is defined as the voluntary occlusion of one or several vessels, and this is achieved by inserting material into the lumen to obtain transient or permanent thrombosis in the downstream vascular bed. There are a number of indications for this approach in urological practice, in particular for the patients with parenchymatous or vascular kidney disease. In this review, we present the different embolization techniques and the principally employed occluding agents, and then we present the principal clinical indications and we discuss other pathologies that may benefit from this non-invasive therapy. The complications, side effects and main precautions associated with this approach are also described.

Embolization of giant renal angiomyolipomas: technique and results

PURPOSE

To evaluate the efficacy and safety of prophylactic embolization of angiomyolipomas (AMLs) larger than 10 cm.

MATERIALS AND METHODS

Sixteen patients (mean age, 41.2 years; 14 women and two men) underwent embolization for 23 AMLs larger than 10 cm. All lesions were embolized by using microcatheters with ethanol and ethiodized oil mixed to a ratio of 7(ethanol) to 3(ethiodized oil). Data collected included pre- and posttreatment AML size, creatinine level, technical success, volume of embolic material used, clinical success, and complications.

RESULTS

The mean AML size before treatment was 15 cm (range, 10-25 cm). Ten of the 16 patients (62%) had all their AMLs treated in one session, whereas six (38%) required multiple sessions. A mean volume of 8.6 mL of the ethanol-ethiodized oil mixture (range, 2-20 mL) was administered per lesion. Patients were followed up for a mean of 29 months (range, 1-80 months). No patient had an increase of 0.2 mg/dL (17.7 mumol/L) or greater in mean serum creatinine level during the follow-up period. Two of the 16 patients (12%) required repeat embolization due to AML regrowth (n = 1) or reperfusion (n = 1) seen at surveillance imaging. One of the 16 patients (6.2%) had an AML hemorrhage 59 months after AML embolization.

CONCLUSIONS

Embolization of giant renal AMLs to decrease the risk of bleeding can be done safely without loss of renal function. Although recurrence was infrequent, additional treatment may be necessary and giant renal AMLs should be followed up with serial imaging studies.

The management of renal angiomyolipomas in a patient with tuberous sclerosis

BACKGROUND

A 17-year-old girl, who was diagnosed with tuberous sclerosis in infancy, presented with multiple bilateral renal masses, the largest of which was 6.0 cm in diameter on the left side.

INVESTIGATIONS

History and physical examination, ultrasonography, MRI, CT, magnetic resonance angiography, and measurement of serial creatinine levels.

DIAGNOSIS

Bilateral angiomyolipomas.Management Observation, serial imaging, embolization and infarction.

[Role of percutaneous arterial embolization in renal pathology]

Therapeutic embolization in renal pathology is used for various conditions in cancerology, traumatology, urology, nephrology and for iatrogenic complications of percutaneous manoeuvers. Any department of vascular radiology may be requested to use this technique, especially in emergent traumatology or palliative cancerology. The authors study the various conditions that may benefit from these procedures and give the highlights of the main indications and the main types of embolic agents used. Complications, side effects and the major precautions are also reviewed.

Embolization of renal angiomyolipomas: short-term and long-term outcomes, complications, and tumor shrinkage

This study retrospectively evaluated outcomes, complications, and tumor shrinkage in renal angiomyolipomas after transcatheter arterial embolization (TAE). All renal angiomyolipoma patients who underwent TAE between August 2000 and December 2008 and had short-term (<or=6 months) or long-term (>6 months) follow-up images were evaluated. Complications and tumor relapse after TAE were reviewed. The sizes of embolized tumors were measured to calculate size reductions and reduction rates after TAE. Differences in tumor size, size reduction, and reduction rate between different time points (pre-TAE, short-term follow-up, and long-term follow-up) and groups (completely and incompletely embolized) were determined. Eleven renal angiomyolipoma patients who had undergone TAE were included. Seven (63.6%) patients had postembolization syndrome and one had abscess formation following TAE. Two patients had a tumor relapse (18.2%). The mean tumor size was 8.57+/-2.66 cm on pre-TAE images. The mean size reduction was 3.1 cm (33.3%) and 3.8 cm (43.0%) at short-term and long-term follow-up. Tumor sizes differed significantly between pre-TAE and short-term (p=0.004) or long-term images (p=0.022) but not between short-term and long-term images (p=0.059). Results stratified by the completeness of embolization indicate that only the short-term size reduction rate differed significantly (p=0.025), while the long-term reduction rate and short- and long-term follow-up tumor size and size reduction were comparable between the two groups. In conclusion, selective TAE is effective for tumor shrinkage in most renal angiomyolipomas, with acceptable complication and relapse rates. Tumor shrinkage occurring within 6 months after TAE may reflect the long-term effect of TAE.

Giant renal angiomyolipoma

A 65-year-old woman from a rural area presented to the surgical service with a very large abdominal lump that the patient had first noticed 8 years previously. The lump had steadily increased in size over time, and the patient had dysuria, weakness and dyspnoea on exertion. On examination she was grossly anaemic with a large retroperitoneal lump that occupied the whole right side of abdomen; the lump was soft to firm in consistency and non-tender. She had no lymphoedema or other palpable lymph nodes. Ultrasound revealed a large retroperitoneal tumour with fatty elements, arising from the right kidney. There was no involvement of the intestines. Findings of the computed tomography scan were typical for renal angiomyolipoma. The patient underwent surgery and the tumour was excised. Four units of blood were transfused preoperatively and in addition two units were given postoperatively. The patient was given thromboprophylaxis perioperatively and in the postoperative period because she was bedridden and could not ambulate. She made an uneventful recovery.

Recurrent retroperitoneal hemorrhage in a patient with tuberous sclerosis complex: a case report

Background

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder. It is characterized by seizures, mental retardation and hamartomatous lesions, including facial angiofibroma, subependymal giant cell astrocytoma, cardiac rhabdomyoma and renal angiomyolipoma (AML). AMLs can bleed severely in the retroperitoneal space.

Case presentation

Herein, we present the case of a TSC patient presenting with recurrent severe episodes of retroperitoneal hemorrhage from AMLs successfully managed by angio-embolization.

Conclusion

Transarterial embolization is effective in preventing and controlling hemorrhage in patients with AMLs of the kidney

Conservative management of giant symptomatic angiomyolipomas in patients with the tuberous sclerosis complex

OBJECTIVE

To present two patients with the tuberous sclerosis complex in whom giant angiomyolipomas (AMLs) were managed conservatively for >20 years, as large (>4 cm) symptomatic AMLs are generally treated with embolization or nephrectomy because of the risks of haemorrhage.

PATIENTS AND METHODS

The first patient initially presented with bilateral renal AMLs replacing >70% of his parenchymal volume, and a large left renal cyst. Since presentation he was hospitalized three times, but has had no transfusions or procedures to treat his AMLs. His renal function has remained stable during this 21-year interval. The second patient initially presented with bilateral renal AMLs that were not amenable to nephron-sparing surgery. After removing her nonfunctioning left kidney, the 24-cm AML in her right kidney was managed conservatively for >20 years, during which she had 44 transfusions and 11 hospitalizations before uncomplicated right nephrectomy and subsequent need for haemodialysis.

CONCLUSION

Conservative management of AMLs can preserve renal function for >20 years in patients with tuberous sclerosis at high risk of end-stage renal disease.

Urological counseling and followup in pediatric tuberous sclerosis complex

PURPOSE

We review our experience with renal manifestations in pediatric patients with the tuberous sclerosis complex, and offer recommendations for urological counseling, followup and treatment of these patients.

MATERIALS AND METHODS

We reviewed clinical notes on 41 patients with the tuberous sclerosis complex followed at our institution from childhood. Patient data were gathered in a database focusing on renal involvement. The latter was assessed by periodic clinical evaluations and ultrasound. The risk of renal involvement was evaluated in relation to patient age, genotypic pattern and number of extrarenal manifestations.

RESULTS

Overall, 15 patients (36.6%) had renal involvement. The latter increased with age and was more common in cases with TSC2 genotypic pattern or multiple extrarenal manifestations. Angiomyolipomas were the most common lesions (11 patients), followed by renal cysts (2) and polycystic kidney disease (2). Cystic lesions were the most common in patients younger than 16 years. Renal failure developed in the 2 patients with polycystic kidney disease by the 2nd decade of life. Overall, treatment was required in 2 cases of symptomatic angiomyolipoma. Both patients were female, and had multiple extrarenal manifestations and bilateral renal involvement. One patient underwent open surgery at age 21.3 years and 1 underwent radiological embolization at age 23.4 years.

CONCLUSIONS

Pediatric patients with the tuberous sclerosis complex should undergo urological evaluation and followup. Although most of the lesions remain silent during childhood, the incidence of renal involvement increases with age. The need for treatment is highest in females with multiple extrarenal manifestations and bilateral renal involvement.