Characterization and Management of Juxtaglomerular Cell Tumor: Analysis of 9 Cases and Literature Review

Aims: Juxtaglomerular cell tumor is a rare kidney tumor. This study aimed to report the clinic features of juxtaglomerular cell tumor and our treatment experience. Methods: The medical records of 9 juxtaglomerular cell tumor patients treated in our hospital from 1997 to 2017 were retrospectively reviewed. Clinical characteristics, immunohistochemical findings, treatments and outcomes were collected. Results: The mean age of 9 patients was 24±8.1 years (range: 18-37). All cases had symptoms of hypertension, hyperaldosteronism, high plasma renin, high plasma angiotensin II. Four cases had hypokalemia. The renal masses were found by enhanced contrast tomography in all patients. One case received ultrasound-guided ablation and was clinically diagnosed with juxtaglomerular cell tumor. Among the remaining 8 cases, 2 cases received nephrectomy while 6 underwent partial nephrectomy. The 8 cases were pathologically diagnosed with juxtaglomerular cell tumor. Immunohistochemical findings showed that juxtaglomerular cell tumor was positive for vimentin, CD34, and actin but negative for chromogranin A. After treatment, all the patients had normal levels of blood pressure, serum renin activity, potassium, and aldosterone. No patients had tumor progress or metastasis within a median follow-up period of 94 (range: 33-241) months. Conclusion: Hypertension combined with hyperaldosteronism and hypokalemia secondary to high plasma renin activity are the typical symptoms of juxtaglomerular cell tumor. Partial nephrectomy is an optimal treatment for juxtaglomerular cell tumor.

What are the Oncologic and Functional Outcomes After Joint Salvage Resections for Juxtaarticular Osteosarcoma About the Knee?

BACKGROUND: Joint salvage surgery for patients with juxtaarticular osteosarcoma remains challenging, especially when the tumor invades the epiphysis. Because patients are surviving longer with current chemotherapy regimens, it is advantageous to retain native joints if possible, especially in young patients. However, the results using joint-preserving tumor resections in this context have not been well characterized. QUESTIONS/PURPOSES: (1) What are the functional outcomes after limb salvage surgery at a minimum of 3 years? (2) What are the oncologic outcomes? (3) Is joint salvage surgery for epiphyseal tumors associated with an increased risk of local recurrence compared with metaphyseal tumors not invading the epiphysis? (4) What are the complications associated with joint salvage surgery? METHODS: Between 2004 and 2013, we treated 117 patients with juxtaarticular osteosarcoma; of those, 43 (38%) were treated with joint salvage surgery, and 41 (95%) of the 43 patients are included in our study. The other two (5%) were lost to followup before 3 years (mean, 4.4 years; range, 3-11 years,). During the period in question, we generally performed joint salvage surgery in these patients when they had a favorable response to chemotherapy, did not have a pathologic fracture or extrusion of the tumor into the joint, and did not have a whole-epiphyseal osteolytic lesion, a large mass, or obvious neurovascular involvement. This report is a followup of an earlier study; the current study includes an additional nine patients, and additional followup of a mean of 19 months for the patients included in the earlier report. We ascertained overall survival and survival free from local recurrence which was estimated using the Kaplan-Meier method, functional status of the limb which was evaluated using the Musculoskeletal Tumor Society (MSTS)-93 scoring system, and recorded reconstructive complications including infection, fracture, skin necrosis, and nonunion. We compared oncologic and functional outcomes between patients with (n = 28) and without tumor extension to epiphysis (n =13). We also compared oncologic and functional outcomes among patients with different adjuvant treatments including microwave ablation (n = 11), cryoablation (n = 12), and navigation-assisted osteotomy (n = 5). Complications were tallied using records from our institutional database. RESULTS: The overall Kaplan-Mayer survival rate was 82% (95% CI, 104-128 months) at 5 years. The overall Kaplan-Meier survivorship from local recurrence was 91% at 5 years (95% CI, 115-133 months). Three patients had a local recurrence, but none had local recurrence in or close to the remaining epiphysis. The MSTS scores ranged from 22 to 30 points, with a median of 28. There were no differences in survival rate, local recurrence, or MSTS scores between patients with a tumor that did not invade the epiphysis and those in whom the tumor did invade the epiphysis. There were differences in MSTS scores among patients with epiphyseal tumor extension in which different adjuvant techniques, including microwave ablation, cryoablation, and navigation-assisted osteotomy, were used. Additional surgical procedures were recorded for 10 patients (24%). Osteonecrosis of the residual epiphysis was detected 13 patients (31%). CONCLUSIONS: Our findings suggest it is possible to salvage joints in selected patients with juxtaarticular osteosarcoma around the knee. The patients who have a favorable response to chemotherapy are the best candidates for this approach. Future studies might explore the role of adjuvant techniques of microwave ablation and cryoablation, particularly when the tumor invades the epiphysis, and whether resections can be facilitated with navigation. LEVEL OF EVIDENCE: Level IV, therapeutic study.