Intraoperative frozen section (FS) margin evaluation is not common practice for patients undergoing breast conservation therapy (BCT), but offers a significant reduction in reoperation. In this study, a technique to allow for more effective freezing of breast tissue was developed to perform FS evaluation of lumpectomy margins (FSM) for all patients undergoing BCT at an ambulatory surgery center. FS evaluation of sentinel lymph node biopsy specimens was performed concurrently. One hundred eighty-one study and 188 control patients, with and without FS evaluation, were compared. Reexcision was reduced 34% (from 48.9% to 14.9%) and reoperation was reduced 36% (from 55.3% to 19.3%) with FS evaluation. Most of the decrease in reoperative rate was because of a decrease in the need for margin reexcision. The number of patients requiring 1, 2, or 3 operations to complete therapy was 84, 92, and 12, respectively, in the control group, and 146, 33, and 2, respectively, in the study group. Lobular subtype, multifocal disease, and larger tumor size (≥2 cm) were significantly associated with failure of FSM to prevent reoperation, but reoperation rates were still significantly decreased in this subgroup of patients (from 75.5% to 43.8%) with FSM. This study highlights an innovative yet simple and adaptable FS approach that resulted in a nearly 3-fold reduction in reoperation for patients undergoing BCT.

AIMS:Recent studies suggest that paediatric renal cell carcinoma (RCC) may represent a distinct group of tumours; however, its biological behaviour and classification remain poorly understood. The aim was to analyse 13 RCCs from patients < or =23 years of age to determine their clinicopathological, immunohistochemical and molecular characteristics. METHODS AND RESULTS:The histological spectrum included: Xp11.2 translocation-associated (6/13 patients, 46%), clear cell (5/13 patients, 38%), papillary (1/13 patients) and unclassified (1/13 patients) types. The Xp11.2 translocation-associated RCCs had a wide morphological spectrum, with high nuclear grade cells with abundant cytoplasm ranging from clear to granular and architecture ranging from solid to papillary. These tumours lacked cytokeratin expression and were confirmed by nuclear reactivity for TFE3 protein. Most of these translocation-associated tumours presented at high stage and had an unfavourable outcome. Three clear cell RCCs had unusual features that have not been previously characterized, including solid and cystic architecture, cells with abundant eosinophilic cytoplasm yet low nuclear grade and focal cytoplasmic inclusions, resembling oncocytoma. Deletion of subtelomeric 3p25 was observed in two of these RCCs. CONCLUSIONS:Xp11.2 translocation-associated RCC represents a predominant and aggressive subtype in the paediatric age group. Increased awareness of this subtype is important due to its heterogeneous morphology.