Abstract Objective The present study was conducted to estimate histologically the proportion of avascularity of fracture ends in case of nonunion of long bones. Methods A total of 15 cases of established quiescent nonunion were operated according to the standard protocol and the fracture ends were evaluated histologically. The biopsied tissue was briefly fixed with formalin, embedded with paraffin (FFPE), and 5-micron sections were stained with hematoxylin and eosin according to standard protocols. Immunohistochemistry with anti-CD31 antibody (JC70A clone, DBS) was performed manually using standard protocols. Results All cases of quiescent nonunion were included; radiologically, 2 cases were oligotrophic, and 13 cases were of atrophic nonunion. A total of 20% of the patients were females, 40% were in the age group between 31and 40 years old, and, radiologically, all cases were of atrophic nonunion. All cases showed positivity for CD-31 on immunohistochemistry. The blood vessel density was category I in 13.33% of the cases and category II in 86.67% of the cases. Four cases presented with mild inflammation and two presented with moderate inflammation. The average vessel count was 10 per high power field in the age groups between 20 and 30, 31 and 40, and 41and 50 years old. The age group between 61 and 70 years old showed an average vessel count of 4 per high power field. The difference in the vessel counts of oligotrophic and atrophic nonunion was not significant. No correlation was observed in the density of vessel count and duration of nonunion Conclusion The nomenclature for the classification of nonunion into atrophic, oligotrophic, and hypertrophic needs revision. Our findings do not support that atrophic and oligotrophic nonunion are histologically different. bones 1 formalin FFPE, FFPE , (FFPE) 5micron micron 5 protocols antiCD31 antiCD anti CD31 CD anti-CD3 JC70A JCA JC clone DBS included radiologically females CD-3 immunohistochemistry 1333 33 13.33 8667 86 67 86.67 30 3 6 7 significant revision different (FFPE antiCD3 CD3 anti-CD CD- 133 13.3 866 8 86.6 13. 86.

Resumo Objetivo O presente estudo estimou a proporção de avascularidade histológica das extremidades das fraturas em caso de pseudoartrose de ossos longos. Métodos No total, 15 casos de pseudoartrose quiescente estabelecida foram operados de acordo com o protocolo padrão e as extremidades da fratura foram avaliadas histologicamente. Em resumo, o tecido biopsiado foi fixado em formalina e embebido em parafina (FFPE); secções de 5 mícrons foram coradas com hematoxilina e eosina de acordo com os protocolos padrões. A imunohistoquímica com anticorpo anti-CD31 (clone JC70A, DBS) foi realizada manualmente segundo protocolos padrões. Resultados Todos os casos de pseudoartrose quiescente foram incluídos; 2 eram de pseudoartrose oligotrófica e 13 eram de pseudoartrose atrófica à radiologia. Destes, 20% eram de pacientes do sexo feminino, 40% de indivíduos entre 31 e 40 anos de idade e todos os casos eram de pseudoartrose atrófica à radiologia. Todos os casos eram positivos para CD-31 à imunohistoquímica. A densidade dos vasos sanguíneos era de categoria I em 13,33% dos casos e de categoria II em 86,67%. Quatro casos apresentavam inflamação branda e dois apresentavam inflamação moderada. O número médio de vasos era de 10 por campo de alta potência na faixa etária de 20 a 30, de 31 a 40 e de 41 a 50 anos. A faixa etária de 61 a 70 anos apresentava, em média, 4 vasos por campo de alta potência. A diferença nos números de vasos em pseudoarthroses oligotróficas e atróficas não foi significativa. Não houve correlação entre a densidade de vasos e a duração da pseudoartrose. Conclusão A nomenclatura de classificação da pseudoartrose em atrófica, oligotrófica e hipertrófica precisa ser revista. Nossos achados não indicam que a pseudoartrose atrófica e oligotrófica sejam histologicamente diferentes. longos total 1 resumo FFPE (FFPE) padrões antiCD31 antiCD anti CD31 CD anti-CD3 clone JC70A JCA JC DBS incluídos radiologia Destes feminino 3 CD-3 1333 33 13,33 8667 86 67 86,67% moderada 30 6 7 apresentava média significativa revista diferentes (FFPE antiCD3 CD3 anti-CD CD- 133 13,3 866 8 86,67 13, 86,6 86,

ABSTRACT Renal cell carcinoma (RCC) is a malignant disease that is often diagnosed at a metastatic stage. The head and neck represent up to 3% of the metastatic RCC, and the paranasal sinus area is one of the least involved sites. Here, we introduce the case of a 74-year-old female patient who presented with a history of traumatic nasal bleed. A cranial computed tomography scan and magnetic resonance imaging showed a fronto-ethmoidal mass with pachymeningeal involvement. A nasal biopsy from the paranasal sinuses was taken. On histopathological examination, metastatic clear cell carcinoma was the main hypothesis, which later was confirmed to be RCC on immunohistochemistry. On further radiological examination, an exophytic mass was depicted in the kidney’s upper and middle pole. The patient had no renal complaints and was asymptomatic. Fronto-ethmoidal sinus is a rare site for metastatic RCC, especially in cases where the patient is asymptomatic. Early detection by keeping RCC metastasis as the differential diagnosis in such cases can lead to early treatment and improve the overall survival of the patient.