The case against fine-needle aspiration cytology for small solid kidney tumors

Role of percutaneous needle biopsy for renal masses

The role of percutaneous renal mass biopsy has expanded considerably in the past 10 years. The incidence of incidentally detected small (< 4 cm) solid renal masses is on the rise, and despite a commensurate increase in nephron-sparing treatment, the mortality rate from renal cell carcinoma remains the same. Earlier detection and treatment have not had dramatic effects on population outcome, implying that not all small renal masses will grow to be life-limiting. Indeed, many small solid renal masses are benign, and among those that are malignant, not all share the same malignant behavior. Percutaneous biopsy provides a minimally invasive method for discriminating benign from malignant renal masses, and portends the potential for stratifying malignant risk. With recent improvements in image-guided equipment and technique, percutaneous renal mass biopsy can be performed safely and effectively, with a low complication rate (< 5%) and a high diagnostic yield (> 90%).

Accuracy of determining small renal mass management with risk stratified biopsies: confirmation by final pathology

PURPOSE

We assess the accuracy of a biopsy directed treatment algorithm in correctly assigning active surveillance vs treatment in patients with small renal masses by comparing biopsy results with final surgical pathology.

MATERIALS AND METHODS

From 1999 to 2011, 151 patients with small renal masses 4 cm or smaller underwent biopsy and subsequent surgical excision. Biopsy revealed cell type and grade in 133 patients, allowing the hypothetical assignment of surveillance vs treatment using an algorithm incorporating small renal mass size and histological risk group. We compared the biopsy directed management recommendation with the ideal management as defined by final surgical pathology.

RESULTS

Biopsy called for surveillance of 36 small renal masses and treatment of 97 small renal masses. Final pathology showed 11 patients initially assigned to surveillance should have been assigned to treatment (8.3% of all patients, 31% of those recommended for surveillance), whereas no patients moved from treatment to surveillance. Agreement between biopsy and final pathology was 92%. Using management based on final pathology as the reference standard, biopsy had a negative predictive value of 0.69 and positive predictive value 1.0 for determining management. Of the 11 misclassified cases, 7 had a biopsy indicating grade 1 clear cell renal cancer which was upgraded to grade 2 (5) or grade 3 (2). After modifying the histological risk group assignment to account for undergrading of clear cell renal cancer, agreement improved to 97%, with a negative predictive value of 0.86 and a positive predictive value of 1.0.

CONCLUSIONS

Our results suggest that compared to final pathology, biopsy of small renal masses accurately informs an algorithm incorporating size and histological risk group that directs the management of small renal masses.

Pretreatment imaging can be used to select imaging guidance, ultrasound alone versus CT plus ultrasound, for percutaneous renal radiofrequency ablation

OBJECTIVE

Although CT is most commonly used for guidance of radiofrequency ablation (RFA) of renal masses, other publications have shown that ultrasound alone may be used. Therefore, we compared the complications and technical effectiveness of renal RFA guided by ultrasound alone versus combined CT and ultrasound guidance.

MATERIALS AND METHODS

We retrospectively analyzed outcomes and complications of percutaneous renal RFA in two groups of patients for whom RFA was guided by either ultrasound alone (group 1) or combined CT and ultrasound (group 2). The sole factor in determining the method of guidance was preablation imaging. All other technical factors were consistent between the two groups.

RESULTS

There were 28 masses in 27 patients in group 1 and 32 masses in 29 patients in group 2. There was an overall major complication rate of 3.3% (2/60). Major complications occurred equally in group 2 (3.1% [1/32]) compared with group 1 (3.6% [1/28]). Overall ablative effectiveness was 93% (26/28) in group 1 and 84% (27/32) in group 2. There was no statistical difference between the two groups.

CONCLUSION

In proper hands, sonography guidance alone is a safe and effective method for performance of renal RFA in preselected cases and can decrease CT utilization. The use of CT is reserved for situations in which pretreatment RFA imaging suggests difficulty in ultrasound mass visualization or when the mass is in close proximity to structures that may be injured by thermal ablation.

Endoscopic ultrasound facilitates histological diagnosis of renal cell cancer

Over two-thirds of renal masses noted incidentally on abdominal CT scans performed for nonurological indications are most likely renal cell carcinoma (RCC). The prognosis in these instances is often quite favorable, as early diagnosis offers the best hope of a complete cure. We report the identification of a RCC incidentally at endoscopic ultrasound (EUS) while an earlier CT scan of abdomen was negative. The mass was biopsied resulting in a histological confirmation of RCC and successful surgical resection.

Open partial nephrectomy in the management of small renal masses

Introduction. Most of the kidney masses are being detected incidentally with smaller size due to widespread use of imaging modalities leading to increased RCC incidence worldwide with an earlier stage. This article reviews the role of open partial nephrectomy (PN) in the management of small renal masses. Material and Methods. Review of the English literature using MEDLINE has been performed between 1963–2008 on small renal masses, partial nephrectomy, kidney cancer, nephron sparing surgery (NSS), radical nephrectomy, laparoscopy, and surgical management. Special emphasis was given on the indications of NSS, oncological outcomes and comparison with open and laparoscopic PN. Results. Overall 68 articles including 31 review papers, 35 human clinical papers, 1 book chapter, and 1 animal research study were selected for the purpose of this article and were reviewed by the authors. Conclusions. Currently, open NSS still remains as the gold standard surgical treatment modality in patients with small renal masses.

Percutaneous Core Biopsy for Renal Masses: Indications, Accuracy and Results

PURPOSE

We evaluated the results, accuracy and clinical incidence of our standard procedure of percutaneous biopsy for solid renal masses.

MATERIALS AND METHODS

From March 1999 to April 2005, 119 percutaneous core biopsies of renal masses were performed. Biopsies were proposed when there was no formal evidence for a carcinoma diagnosis on computerized tomography.

RESULTS

Benign lesions were diagnosed in 24 biopsies (20.1%), including oncocytoma in 13, angiomyolipoma in 5 and chronic pyelonephritis in 5. Malignancy was identified in 70 biopsies (58.8%), including 57 renal carcinomas (conventional renal cell in 41, papillary in 12 and chromophobe in 4), 4 transitional cell carcinomas, 8 metastases and 1 lymphoma. For 25 biopsies (21%) no accurate diagnosis was possible, including 12 that showed inflammatory tissue and 13 with normal or necrotic tissue. These inconclusive biopsies prompted repeat biopsy in 13 patients, in whom a total of 11 malignant lesions were diagnosed. A total of 64 nephrectomies were performed with a biopsy accuracy for histopathological tumor type and Fuhrman nuclear grade of 86% and 46%, respectively. A period of watchful waiting was proposed for 31 patients (34.2%) and no renal malignancies were found. Computerized tomography showed stabilization or disappearance of the initial renal mass.

CONCLUSIONS

Percutaneous renal tumor biopsies are safe, cost-effective and often conclusive for an acute histological diagnosis. This procedure could be decisive for choosing the optimal treatment, particularly to avoid nephrectomy for benign lesions. Biopsies should not be considered a routine procedure but they could be indicated when there is a lack of radiological evidence in elective patients.

Management of renal tumors by image-guided radiofrequency ablation: experience in 105 tumors

Aims

In this article we present our experience with radiofrequency ablation (RFA) in the treatment of 105 renal tumors.

Materials and Methods

RFA was performed on 105 renal tumors in 97 patients, with a mean tumor size of 32 mm (11–68 mm). The mean patient age was 71.7 years (range, 36–89 years). The ablations were carried out under ultrasound (n = 43) or CT (n = 62) guidance. Imaging follow-up was by contrast-enhanced CT within 10 days and then at 6-monthly intervals. Multivariate analysis was performed to determine variables associated with procedural outcome.

Results

Eighty-three tumors were completely treated at a single sitting (79%). Twelve of the remaining tumors were successfully re-treated and a clinical decision was made not to re-treat seven patients. A patient with a small residual crescent of tumor is under follow-up and may require further treatment. In another patient, re-treatment was abandoned due to complicating pneumothorax and difficult access. One patient is awaiting further re-treatment. The overall technical success rate was 90.5%. Multivariate analysis revealed tumor size to be the only significant variable affecting procedural outcome. (p = 0.007, Pearson χ²) Five patients had complications. There have been no local recurrences.

Conclusion

Our experience to date suggests that RFA is a safe and effective, minimally invasive treatment for small renal tumors.

The indications for partial nephrectomy in the treatment of renal cell carcinoma

Partial nephrectomy is performed more frequently for small, incidentally discovered, low-stage renal tumors. Importantly, one should distinguish the imperative indications for such surgery from the relative and elective indications, while taking contraindications to nephron-sparing surgery into account. The main advantage of partial nephrectomy over radical nephrectomy is the avoidance of renal insufficiency; the major disadvantages include the possibility of local recurrence and perioperative complications. In this article, the literature on nephron-sparing surgery was reviewed in order to put the management of renal cancer into a modern perspective.

FDG PET in solitary metastastic/secondary tumor of the kidney: A report of three cases and a review of the relevant literature

Metastatic tumors or secondary lymphoma of the kidney are rare and can often be missed on conventional computed tomography (CT) imaging. On the other hand, many types of metastatic tumor or lymphoma can be detected clearly as hotspots of elevated uptake on FDG PET. However, excreted FDG present in the urinary tract mimics these findings and interferes with image reading. Careful investigation of the renal cortex by FDG PET and review of anatomical images, such as the findings of CT and MRI, have important roles in the detection of renal tumor. Here, we present three cases of solitary metastatic/secondary tumor of the kidney, and discuss the features of the lesions on FDG PET in comparison with their appearance on CT.

Evaluation of imaging-guided fine-needle percutaneous biopsy of renal masses

To evaluate the utility of imaging-guided fine-needle percutaneous biopsy of renal masses, we conducted a prospective analysis of our imaging-guided procedures from January 1999 to February 2003. We performed 54 percutaneous core biopsies in 46 patients. Fluoro-computed tomography and ultrasound guidance were respectively used in 48 and six cases. One to four specimens were obtained by using an 18-gauge automated coaxial biopsy system. We reviewed the patients medical records, pathology results, and imaging studies. Core biopsy results were compared with surgical pathology (n=27) or clinical follow-up (n=19). All biopsies provided sufficient material for analysis. The mean tumor size was 33 mm. Biopsy findings were positive for malignancy in 31 cases; histologic diagnoses included renal cell carcinoma (n=23), transitional cell carcinoma (n=5), and metastasis (n=3). Biopsy revealed 15 benign diagnoses: oncocytoma (n=6), hemorrhagic renal cyst (n=3), chronic nephritis (n=3), angiomyolipoma (n=2), and mycotic renal abscess (n=1). The average follow-up period for patients with benign diagnoses was 16 months. Biopsy results showed normal renal parenchyma in eight of 54 procedures, all of which had recuperated by subsequent biopsies. No immediate complications occurred after the procedures. Imaging-guided percutaneous core biopsy is a safe and accurate method for the evaluation of renal masses.

A renal mass in the setting of a nonrenal malignancy: When is a renal tumor biopsy appropriate?

BACKGROUND

Frequently, a renal mass is identified when patients with cancer undergo studies for staging or surveillance. In determining whether it represents a metastasis, patients are frequently subjected to percutaneous renal biopsies. The authors evaluated their experience with this dilemma to formulate management guidelines.

METHODS

The authors reviewed the medical records of 100 consecutive patients with nonrenal malignancies diagnosed with renal masses at presentation or follow-up. Renal mass histology was available for all patients after nephrectomy or biopsy. Clinical characteristics were assessed to identify factors predictive for a renal metastasis versus a primary renal neoplasm.

RESULTS

The only factors predictive of a metastasis to the kidney were progression of the nonrenal malignancy and lack of enhancement of the renal mass (P < 0.0001). Forty-six patients (46%) had evidence of progression of their nonrenal malignancy in addition to the renal mass. In these patients, the probability of a metastasis to the kidney was 86% (95% confidence interval [CI], 57.2-98.2%) without renal mass enhancement and 32% (95% CI, 14-55%) with enhancing renal masses. None of the 54 patients without signs of progression of their nonrenal malignancy proved to have metastases to the kidney, regardless of the imaging characteristics of the mass (zero probability; 95% CI, 0-7%; P < 0.001).

CONCLUSIONS

In patients presenting with renal masses and another clinically localized malignancy, renal mass biopsies were not indicated, as the mass rarely represented a metastasis. These patients may opt for close surveillance or extirpation based on the prognosis of their nonrenal malignancy.

The radiographic evolution of radio frequency ablated renal tumors

PURPOSE

Radio frequency ablation (RFA) of renal tumors is a relatively new technology. Few groups are familiar with the posttreatment appearance of these lesions and how they differ from cryoablated renal masses. We describe the evolution of the appearance of these lesions on followup contrast enhanced (CE) computerized tomography (CT).

METHODS AND MATERIALS

A total of 64 consecutive renal tumors treated with RFA from April 2000 to September 2003 for which posttreatment CE-CT was done were included in this study. CE-CT was reviewed at 6 weeks, 3 months, 6 months and every 6 months thereafter to determine the characteristic features and evolution of these lesions.

RESULTS

Renal tumors were treated with CT guided percutaneous (34), laparoscopic (28) or open (2) RFA. At a median followup of 13.7 months (range 6 weeks to 29 months) 62 RFA lesions demonstrated an absence of contrast enhancement on CE-CT. Treated endophytic tumors developed a low density, nonenhancing, wedge-shaped defect with fat infiltration seen between the ablated tissue and normal parenchyma. Treated exophytic tumors retained a configuration similar to that of the original with a lack of contrast enhancement and minimal shrinkage. Percutaneous treated lesions developed a peritumor scar or halo that demarcated ablated and nonablated tissue (perirenal fat). Persistent tumor was marked by contrast enhancement within the ablation borders of the original mass in 1 case, whereas tumor recurred after initial successful ablation with an enhancing nodule in 1.

CONCLUSIONS

The radiographic features and evolution of radio frequency ablated renal tumors are unique. Successfully treated tumors demonstrated no contrast enhancement, minimal shrinkage and occasional retraction from normal parenchyma by fat infiltration.

Characteristics of image-detected solid renal masses: Implication for optimal treatment

BACKGROUND

Solid renal masses are found increasingly. Further analysis of the characteristics of solid renal masses is useful for optimal treatment.

METHODS

A retrospective analysis of all solid renal masses was conducted from December 1998 to May 2003 at the Urology Department, Central University Hospital of Saint-Etienne, France. A total of 162 solid renal masses were treated. The preoperative imaging diagnosis of ultrasound and computed tomography, and final pathological results were reviewed.

RESULTS

One hundred and forty-five tumors were pathologically confirmed to be renal cell carcinomas (RCC); 17 tumors (10.5%) were benign. There were eight renal oncocytomas, eight renal angiomyolipomas and one benign mixed epithelial/stroma tumor. Three oncocytomas and five angiomyolipomas were strongly suspected before surgery. The majority of the benign tumors were < or =4 cm. The percentage of small benign tumors (< or =4 cm) was significantly higher than large benign tumors (>4 cm). Although it is possible to use imaging to detect some benign tumors, the majority of benign tumors cannot be diagnosed definitively by imaging before surgery.

CONCLUSIONS

Malignancy in solid renal masses is tumor-size related. Benign solid renal tumors appear mainly as small-sized tumors. The preoperative differentiation between an RCC and a benign tumor can be difficult. Our data suggest that a biopsy is necessary in selected patients to achieve the maximum accuracy in order to provide optimal treatment.

Percutaneous biopsy of renal masses: sensitivity and negative predictive value stratified by clinical setting and size of masses

OBJECTIVE

The purpose of our retrospective study was to evaluate the sensitivity and negative predictive value of percutaneous biopsy of renal masses stratified by clinical setting and the size of the mass.

MATERIALS AND METHODS

We categorized 115 consecutive percutaneous biopsies of renal masses in 113 patients into four clinical settings and three groups of mass sizes. The sensitivity and negative predictive value were computed (with 95% confidence intervals [CI]) for each clinical setting and for each size group.

RESULTS

For all procedures (n = 115), the sensitivity and negative predictive value were 90% (95% CI, 81-95%) and 64% (95% CI, 44-81%), respectively. For patients with a known malignancy who presented with a renal mass (n = 55), the sensitivity and negative predictive value were 90% (95% CI, 78-96%) and 38% (95% CI, 10-74%), respectively. For patients with no known malignancy and suspected unresectable tumor (n = 36), the sensitivity and negative predictive value were 92% (95% CI, 76-98%) and 0%, respectively. For patients with no known malignancy who presented with a cystic mass (n = 16), the sensitivity and negative predictive value were 33% (95% CI, 2-87%) and 87% (95% CI, 58-98%), respectively. For patients who were not surgical candidates with a renal cell carcinoma (n = 8) that was thought to be resectable, both the sensitivity and negative predictive value were 100%. For masses 3 cm and less (n = 31), the sensitivity and negative predictive value were 84% (95% CI, 63-95%) and 60% (95% CI, 27-86%), respectively. For masses between 4 and 6 cm (n = 42), the sensitivity and negative predictive value were 97% (95% CI, 83-100%) and 89% (95% CI, 51-99%), respectively. For masses greater than 6 cm (n = 42), the sensitivity and negative predictive value were 87% (95% CI, 71-95%) and 44% (95% CI, 15-77%), respectively.

CONCLUSION

Percutaneous renal mass biopsy has a high sensitivity in three clinical settings: patients with a known malignancy, patients with no known malignancy and suspected unresectable tumor, and nonsurgical patients with a mass suspected to be a resectable renal cell carcinoma. Negative results in small (< or = 3 cm) and large (> 6 cm) masses should be viewed with caution.

Early experience with percutaneous radiofrequency ablation of small solid renal masses

OBJECTIVE

Incidental small renal-cell masses are often seen in elderly patients with significant comorbidity who are unfit to undergo major surgery. This study was conducted to determine the safety and efficacy of percutaneous imaging-guided radiofrequency ablation in the management of small solid renal masses, almost all of which are renal cell cancers.

CONCLUSION

Early experience suggests that radiofrequency ablation is a safe, well-tolerated, and minimally invasive therapy for patients with solid renal masses. In the era of nephron-sparing surgery, radiofrequency ablation may have a role in the management of small problematic renal masses.

Nephron-sparing surgery for localized renal cell carcinoma with a normal contralateral kidney: a European three-center experience

OBJECTIVES

To assess the long-term effectiveness and safety of nephron-sparing surgery for the treatment of localized renal cell carcinoma with a normal contralateral kidney.

METHODS

Since 1973, 118 patients have undergone nephron-sparing surgery for renal cell carcinoma on an elective basis at our institutions. The vast majority of these tumors were incidental findings, with a mean tumor diameter of 3.35 cm (range 0.7 to 5.6). The median follow-up was 8.5 years (range 0.5 to 18), and of those patients alive, 27 (28%) were followed up for more than 10 years.

RESULTS

The pathologic stage was pT1N0M0 in 110 cases (93.2%) and pT3aN0M0 in 8 (6.7%); 59 were grade 1, 52 were grade 2, and 7 were grade 3. Complications occurred in 4 patients, including retroperitoneal bleeding in 1 treated by reoperation, urinomas in 2, and ureteral stricture in 1 treated conservatively. Renal function remained normal during the whole follow-up period, and slight proteinuria was observed in 13 patients. The 10-year distant and local recurrence rate was 4% and 3.9%, respectively. The cancer-specific 5, 10, and 15-year survival rate was 97.3%, 96.4%, and 96.4%, respectively.

CONCLUSIONS

Our experience, based on a long median follow-up, suggests that nephron-sparing surgery on an elective basis can achieve long-term survival for the treatment of incidental and low-stage renal cell carcinomas without compromising the efficacy of cancer treatment.

Evaluation of sonographically guided percutaneous core biopsy of renal masses

OBJECTIVE

Our objective was to determine the utility of sonographically guided percutaneous core biopsy to evaluate renal masses.

MATERIALS AND METHODS

We conducted a retrospective analysis of our imaging-guided procedures from January 1999 to June 2001. We performed 26 sonographically guided percutaneous core biopsies of renal masses in 26 patients. From two to five specimens were obtained from a single mass in each patient using an 18-gauge automated biopsy system. We examined the patients' medical records, pathology results, and imaging studies. Core biopsy results were compared with surgical pathology (n = 6) or clinical follow-up (n = 20).

RESULTS

All biopsies provided sufficient material for analysis. Biopsy findings were positive for malignancy in 19 (73%) of 26 masses. Histologic diagnoses included renal cell carcinoma were (n = 11), metastasis (n = 3), lymphoma (n = 2), and transitional cell carcinoma (n = 2). Specific cell type characterization could not be made on one biopsy, but the specimens were highly suspicious for malignancy. Biopsy revealed seven (27%) of 26 benign diagnoses: oncocytoma (n = 3), angiomyolipoma (n = 2), and fibrosis (n = 2). The average follow-up period for patients with benign diagnoses was 10 months. One case of surgically proven necrotic pyelonephritis was mischaracterized as fibrosis at core biopsy. Sonographically guided percutaneous core biopsy of renal masses showed a sensitivity of 100% and a specificity of 100% for the diagnosis of malignancy. The core specimens yielded a specific diagnosis in 92% (24/26) of masses. No immediate complications occurred after the procedure. One patient developed a pseudoaneurysm that presented 3 months after the biopsy. CONCLUSION. Sonographically guided percutaneous core biopsy is a reliable and accurate method for evaluating renal masses.

Fine-needle percutaneous biopsy of renal masses with helical CT guidance

PURPOSE

To evaluate the feasibility, accuracy, and clinical role of fine-needle percutaneous biopsy of renal masses, with helical computed tomographic (CT) guidance.

MATERIALS AND METHODS

In 63 patients (mean age, 62 years), 73 biopsies were performed. The median tumor size was 4.0 cm. Tumor biopsy was performed with an 18-gauge needle by using helical CT guidance in an outpatient setting. Two to four cores per tumor were obtained.

RESULTS

Biopsy material was insufficient for analysis in 15 (21%) procedures. The median tumor size of failed or successful biopsies was 3.0 or 4.8 cm, respectively (P =.03). A benign lesion was found at eight biopsies. Two samples were suspicious for renal cell carcinoma (RCC). RCC was found in 38 biopsy samples. The remainder were transitional cell carcinoma, metastasis, lymphoma, or sarcoma. Twenty-six patients underwent nephrectomy. The accuracies of biopsy for histopathologic and Fuhrman nuclear grade evaluation were 89% and 78%, respectively. For tumors of 3.0 cm or smaller or larger than 3.0 cm, 37% (11 of 30) or 9% (four of 43) had failure of biopsy, respectively (P =.006). No substantial morbidity occurred.

CONCLUSION

Fine-needle biopsy with helical CT guidance is accurate for the histopathologic evaluation of renal masses without morbidity. Indications are renal lesions that do not have the typical radiologic features of RCC, Bosniak category III or IV cystic lesions, and locally advanced or metastatic RCC.

Successful grading of renal-cell carcinoma in fine-needle aspirates

Early-stage renal-cell carcinoma is more frequently diagnosed due to more frequent use of advanced radiologic techniques. Partial nephrectomy may be curative for small tumors and may sometimes be necessary if the opposite kidney is functionally compromised. This therapeutic option is however not possible in high-grade neoplasms. In the current study, we attempted to grade cases of renal-cell carcinoma on smears obtained from preoperative fine-needle aspirates (FNA). Eighteen cases of histologically proven renal-cell carcinoma formed the basis of this study. FNAs were performed prior to nephrectomy. FNA smears were blindly reviewed, and the cases were evaluated for cellularity, nuclear to cytoplasmic (N/C) ratios, nuclear pleomorphism, and the presence of naked nuclei and prominent nucleoli; cases were graded according to the presence or absence of these criteria and their combination. The cases were cytologically graded from grade I-IV and then were given a low grade if the tumor was considered grade I or II, or high grade if the tumor was considered grade III or IV. The histology of the neoplasms was reviewed, and the tumors were graded according to the Fuhrman nuclear grading system. Correlation between the cytologic and histologic grades within the same histologic grade was seen in 13 of the 18 cases (72.2%). The difference was no more than one grade for each discrepancy. When grading as high or low grade was used, agreement was seen in 100% of the cases. The most reliable cytologic features seen on cytology distinguishing low- from high-grade tumors were the N/C ratio and the presence or absence of nucleoli. Pleomorphism, naked nuclei, and increased cellularity were less distinguishing features. We conclude that grading of renal-cell carcinoma can be reliably achieved in FNA material. Preoperative FNAs can thus be performed on small renal neoplasms with subsequent conservative treatment if the tumor proves to be low grade.

Evaluation of fine-needle aspiration cytology for renal masses

OBJECTIVE

To evaluate the accuracy and use of fine-needle aspiration (FNA) cytology for the diagnosis of renal masses because with the improved quality and increasing use of ultrasonography and computed tomography (CT), asymptomatic renal masses, particularly small (< 5 cm) tumours, are being discovered more frequently.

PATIENTS AND METHODS

Between 1995 and 1997, 49 patients (mean age 67.5 years, range 42-88, 34 men and 14 women) underwent FNA of a solid or complex cystic mass under radiological guidance. All masses were further evaluated and staged by CT. Solid masses were divided according to size (< 5 cm and >/= 5 cm). Patients were followed up to the determination of a final diagnosis on tissue histology, after nephrectomy where possible.

RESULTS

Thirty-six patients had histologically confirmed carcinoma at nephrectomy, and nine had presumed carcinoma (four unfit for surgery, five with advanced malignancy). The remaining four patients had benign diagnoses. FNA produced insufficient sample in eight cases (16%). The sensitivity was 89% for large (>/= 5 cm) solid masses, 64% for small (< 5 cm) solid masses and 50% for complex cysts.

CONCLUSION

FNA does not contribute to the diagnosis of malignancy in large (> 5 cm) masses, as good radiological imaging is nearly always diagnostic. For smaller (< 5 cm) masses and complex cysts, FNA can occasionally confirm malignancy, but lack of diagnostic yield and low sensitivity means that FNA is unreliable as a diagnostic tool and will rarely help in the routine management of these patients.

Fine-needle aspiration of renal masses in adults: analysis of results and diagnostic problems in 108 cases

Fine-needle aspiration (FNA) biopsy of the kidney has a traditionally well-defined role in the diagnosis and treatment of renal lesions. Recent improvements in renal imaging techniques have also brought renal FNA to the forefront, since small and asymptomatic renal masses are increasingly being detected. Before the physician institutes a treatment plan, such lesions usually require a definitive diagnosis that is best provided by FNA. To assess various aspects of renal FNA, including specimen adequacy, questionable cytologic patterns, and diagnostic pitfalls, we retrospectively evaluate our experience with 108 FNA biopsies performed for the evaluation of renal masses in adults. For each case, the smears were reviewed and correlated with tissue sections from cell blocks, surgical specimens, or autopsy material, when available. The cytologic diagnoses were confirmed by cell block (59 cases), nephrectomy or autopsy (35 cases), or clinical follow-up. Of the 108 FNA biopsy samples, 17 showed evidence of blood, soft tissue, necrotic material, glomeruli, or tubular cells and were classified as unsatisfactory. The following diagnostic categories were noted in the 91 satisfactory aspirates: renal abscess (four cases), benign cyst (30 cases), suspicious lesions (11 cases), and malignant lesions (46 cases). In four cases of renal abscess, FNA found abundant clusters of neutrophils. For the 30 cases interpreted on cytologic evidence as benign cysts, the diagnosis was confirmed in 28 cases; the two remaining cases were acquired cystic kidney and cystic renal-cell carcinoma, respectively. Among the 11 suspicious lesions, the final diagnoses were one benign simple cyst, one angiomyolipoma, two multilocular cystic nephromas, two adult polycystic kidneys, one acquired cystic kidney, three cystic papillary renal-cell carcinomas, and one solid renal-cell carcinoma. Cases classified as suspicious shared characteristic cytologic patterns that distinguished them from simple benign cysts and from classic renal-cell carcinoma. Among the 46 malignant lesions, as evidenced on cytologic examination, 27 were renal-cell carcinomas, five were transitional-cell carcinomas, four were lymphomas, one was a small-cell undifferentiated carcinoma, and nine were metastatic carcinomas. False-positive or false-negative cases were not encountered in this category. In conclusion, FNA is an excellent method to diagnose space-occupying lesions of the kidney. For cystic lesions, cytologic-radiographic correlation is needed to avoid misinterpretation. Our study defines a spectrum of suspicious patterns characteristic of a group of renal lesions that are distinct from both benign simple cyst and straightforward renal malignancy.

Partial nephrectomy for renal cell carcinoma can achieve long-term tumor control

PURPOSE

Partial nephrectomy is becoming more widely accepted as alternative treatment for small renal cell carcinoma. To analyze its value in tumor control and its complication rate a retrospective study was done.

MATERIALS AND METHODS

A total of 76 patients underwent kidney sparing surgery, which was required in 25 and in the presence of a normal contralateral kidney in 51. Tumor size varied between 0.9 and 15 cm. Simple enucleation was done in 4 and partial nephrectomy in all other cases. The patients were followed every 3 months during year 1, every 4 months during years 2 and 3, and every 6 months during years 4 and 5 postoperatively. Mean followup is 75 months.

RESULTS

Eight patients had postoperative complications, most often hemorrhage. None of the patients had local recurrence, although in 3 systemic disease developed.

CONCLUSIONS

Nephron sparing surgery is more challenging than radical nephrectomy and, therefore, can be more complicated. The selection of suitable candidates is the key to success. Many patients can benefit from nephron sparing surgery for small easily resectable renal cell carcinoma even in presence of a normal contralateral kidney. Randomized trials are needed to establish the definitive role of this approach in kidney cancer treatment.

Partial nephrectomy for renal cell carcinoma can achieve long-term tumor control

PURPOSE

Partial nephrectomy is becoming more widely accepted as alternative treatment for small renal cell carcinoma. To analyze its value in tumor control and its complication rate a retrospective study was done.

MATERIALS AND METHODS

A total of 76 patients underwent kidney sparing surgery, which was required in 25 and in the presence of a normal contralateral kidney in 51. Tumor size varied between 0.9 and 15 cm. Simple enucleation was done in 4 and partial nephrectomy in all other cases. The patients were followed every 3 months during year 1, every 4 months during years 2 and 3, and every 6 months during years 4 and 5 postoperatively. Mean followup is 75 months.

RESULTS

Eight patients had postoperative complications, most often hemorrhage. None of the patients had local recurrence, although in 3 systemic disease developed.

CONCLUSIONS

Nephron sparing surgery is more challenging than radical nephrectomy and, therefore, can be more complicated. The selection of suitable candidates is the key to success. Many patients can benefit from nephron sparing surgery for small easily resectable renal cell carcinoma even in presence of a normal contralateral kidney. Randomized trials are needed to establish the definitive role of this approach in kidney cancer treatment.