Calyceal diverticulum simulating a renal tumor.

Calyceal diverticulum (CD) is a rare anatomic anomaly with an incidence of 0.2% to 0.6% in the patients undergoing renal imaging. They are considered benign lesions and malignancy is exceedingly rare. For diagnosis it is suggested to perform a multiphasic contrast-enhanced computed tomography (CT) evidencing a diverticulum of the pelvicalyceal system with thin-walled cavities communicating with the central collecting system. However, they can be usually mistaken as kidney cancers leading to unjustified nephrectomy. Here, we present a case of a 34-year-old patient who underwent surgery in 2022 due to suspected kidney cancer and histopathological analysis surprisingly reported a CD.

[Kidney involvement in Idiopathic Light Chain disease. Report of one case]. / Enfermedad renal por depósito idiopático de cadenas livianas: Caso clínico.

Idiopathic Light Chain disease (ILCD) is a systemic disease characterized by a deposit in different organs of light chain monoclonal immunoglobulins, produced by an abnormal clone of B cells. It is usually found in the course ofa plasma cell dyscrasia and in other lymphoproliferative alterations; however it may occur in absence of any hematologic disease and is denominated as idiopathic. We report a 51-year-old mole admitted to the hospital due to anasarca. Laboratory evaluation showed a serum creatinine of 1.4 mg/dl, a serum albumin of1.6 g/dl, a serum cholesterol of 687 mg/dl and a proteinuria of 5.3 g/day Light chains with a predominance of a monoclonal component were identified in urinary proteins by electrophoresis and kappa chains were identified by immunofixation. A renal biopsy showed a diffuse nodular glomerulopathy with a 35% tubular atrophy and interstitial sclerosis. Electrón microscopy confirmed light chain deposition. The bone marrow biopsy showed a myeloid hyperplasia. The patient was initially treated with methylprednisolone and plasmapheresis with a reduction in serum creatinine and disappearance of urinary kappa component. Albuminuria persisted and a malnutrition-inflammatory complex syndrome was diagnosed. Hemodialysis with ultrafiltration was started along with cyclophosphamide. The patient received hemodialysis for six months and continued with methylprednisolone.

Histamine H4 Receptor Expression in Triple-negative Breast Cancer: An Exploratory Study.

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype. There are neither universally accepted prognostic markers nor molecular targets related to TNBC. The histamine H4 receptor (H4R) has been characterized in TNBC experimental models, demonstrating its critical role in tumor development and progression. In this study, H4R expression was compared in breast cancer subtypes and correlated with clinical features using The Cancer Genome Atlas data (Pan-Cancer Atlas). The H4R status was further evaluated by immunohistochemistry in 30 TNBC human samples in relation to clinicopathological parameters. Results indicate that H4R was downregulated in basal-like/TNBC compared with luminal A and normal breast-like tumors. The higher expression of H4R was associated with improved progression-free and overall survival outcomes in basal-like/TNBC. H4R immunoreactivity was detected in about 70% of tumors, and its expression was positively correlated with the levels in the histologically normal peritumoral tissue. High H4R expression in peritumoral tissue correlated with reduced number of lymph node involvement and unifocal TNBC, while it was associated with increased patient survival. In conclusion, the H4R might represent a potential prognostic biomarker in TNBC. Further studies in large cohorts are needed to better understand the significance of H4R in breast cancer biology.

Multicenter study of diffuse pleural mesothelioma. Histopathological and immunohistochemical features.

The pathological diagnosis of diffuse pleural mesothelioma (DPM) contributes to treatment selection and clinical trials interpretation. To know its characteristics and evaluate the viability of comprehensive pathological diagnosis of DPM in Argentina we did a retrospective descriptive study of DPM cases reported from 2009 to 2018. We analyzed 398 cases corresponding to 238 (60%) men and 160 (40%) women, median age 66 years, from surgical biopsies (78%), small biopsies (16.5%) and surgical resections (5.5%). The 77% were epithelioid (E-DPM), 12% biphasic, 10% sarcomatoid, and 4 cases transitional variant. In E-DPM the main pattern was tubular in 36% and solid in 33%. There was a second pattern in 179 cases. Considering the main pattern and the second together, 48% presented tubular subtype and 48% solid subtype. Stroma, necrosis, and nuclear score showed significant differences between E-DPM and non-epithelioid mesotheliomas. Overall tumor grade was predominantly low in E-DPM, except for 42% of the solid main pattern. We recognized the transitional variant extensively in 4 cases and focally in 8. The immunohistochemical antibody panel used included pan-cytokeratin, calretinin, WT-1, cytokeratin 5, CEA and TTF-1. The expression of cytokeratin 5, calretinin and WT-1 was lower in the sarcomatoid type (43%, 87 and 37%) than in the epithelioid type (92%, 98% and 93%). This study highlights the tumor heterogeneity of DPM that shows the diagnostic difficulty, and the feasibility of evaluating histological aggressiveness in E-DPM, B-DPM and S-DPM in our country.

El diagnóstico patológico del mesotelioma pleural difuso (MPD) contribuye a la selección del tratamiento y a la interpretación de los ensayos clínicos. Para conocer sus características y evaluar la viabilidad del diagnóstico patológico de MPD en Argentina se realizó un estudio descriptivo retrospectivo de los casos de MPD informados de 2009 a 2018. Se analizaron 398 casos correspondientes a 238 (60%) hombres y 160 (40%) mujeres, mediana de edad de 66 años, a partir de biopsias quirúrgicas (78%), biopsias pequeñas (16.5%) y resecciones quirúrgicas (5.5%). El 77% fue epitelioide (E-MPD), 12% bifásicos, 10% sarcomatoides y 4 casos variante transicional. En E-MPD se encontró como patrón principal el tubular en 36% y el sólido en 33%. Hubo un segundo patrón en 179 casos. Considerando el principal y el segundo patrón en conjunto, el 48% presentó subtipo tubular y el 48% subtipo sólido. El estroma, la necrosis y el score nuclear mostraron diferencias significativas entre E-MPD y mesoteliomas no epitelioides. El grado general del tumor fue predominantemente bajo en E-MPD, a excepción del 42% del patrón principal sólido. Reconocimos la variante transicional en forma extensa en 4 casos y focalmente en 8. La expresión de citoqueratina 5, calretinina y WT-1 fue menor en el tipo sarcomatoide (43%, 87 y 37%) que en el tipo epitelioide (92%, 98% y 93%). Este estudio destaca la heterogeneidad tumoral de MPD que evidencia la dificu ltad en el diagnóstico y la viabilidad de evaluar la agresividad histológica en E-MPD, B-MPD y S-MPD en nuestro país.

Non-invasive follicular neoplasm with papillary-like nuclear features: a challenging and infrequent entity in Argentina.

PURPOSE: Non-invasive encapsulated follicular variant of papillary thyroid cancer was reclassified as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). These neoplasms have an extremely low malignant potential. The aim of this study was (1) to assess the prevalence of NIFTP in patients with papillary thyroid carcinoma, (2) to evaluate their outcomes, and (3) to determine their molecular profile. METHODS: Multicenter, descriptive, retrospective study. Patients with papillary thyroid cancer diagnosed from January 2006 to December 2016 from 11 referral centers were included. Diagnosis of NIFTP was based on criteria described by Nikiforov et al. in 2018. At least two pathologists agreed on the diagnosis. Two thousand six hundred and seventy-seven papillary thyroid cancer patients were included; 456 (17%) of them were follicular variant papillary thyroid cancer, and 30 (1.12%) fulfilled diagnostic criteria for NIFTP. RESULTS: Each of the 30 included patients underwent a total thyroidectomy, and 50% were treated with radioiodine (median dose 100 mCi). After a median follow-up of 37 months, 84% of patients had an excellent response, 3% had an indeterminate response and data was missing in the remaining 13%. No metastatic lymph nodes, distant metastases or recurrences were found. RAS mutations were detected in 4 patients (13%). CONCLUSION: The prevalence of NIFTP in our series is amongst the lowest reported. Excellent outcomes of patients underscore their low malignant potential. Molecular findings differ from other series, probably related to environmental or ethnic features of our population and the meticulous criteria for diagnosing NIFTP.

Downregulation of megalin, cubilin, ClC-5 and podocin in Fabry nephropathy: potential implications in the decreased effectiveness of enzyme replacement therapy.

Fabry disease is an X-linked disorder due to mutations in α-galactosidase A, resulting in the accumulation of enzyme substrates and cell malfunction. Kidney involvement is frequent, affecting all native kidney cell types. Podocyte damage results in proteinuria and chronic kidney disease. End-stage kidney disease is the rule in middle-aged males and some females with the classic phenotype. In podocytes and kidney proximal tubular cells, megalin is one of the molecules involved in enzyme replacement therapy (ERT) cellular absorption. After podocyte damage, podocin concentration is decreased and contributes to progressive proteinuria. We report in a male and a female patient the decreased expression of megalin, cubilin, ClC-5 and podocin compared to controls and chronic kidney disease (CKD) biopsies. Moreover, the decrease in ClC-5, a molecule engaged in endosomal-lysosomal acidification, could also affect ERT. These findings may partially explain some of the dysfunctions described in Fabry nephropathy and could highlight possible alterations in the pharmacokinetics of the delivered enzyme.

Undifferentiated carcinoma with osteoclast-like giant cells of the pancreas diagnosed by endoscopic ultrasound guided biopsy.

Undifferentiated pancreatic carcinoma with osteoclast-like giant cells is a rare tumour that has been published under a wide variety of names, including pleomorphic carcinoma, giant cell carcinoma, sarcomatoid carcinoma and carcinosarcoma, among others. For these reasons and its low frequency, the reports of these tumours are scarce and frequently lead to confusion with other entities which present with giant cells. We present the case of a patient with obstructive jaundice and a mixed cystic and solid pancreatic mass, accompanied by multiple hepatic lesions. The histological study of the material obtained by endoscopic ultrasound guided biopsy demonstrated a proliferation of atypical epithelioid cells, accompanied by a spindle cell component with marked pleomorphism and numerous osteoclast-like giant cells. The epithelioid component showed positive immunostaining with cytokeratin cocktail and cytokeratin 7. The spindle cell component showed coexpression of cytokeratins and vimentin. The osteoclast-like giant cells were positive for CD68. Protein p53 was overexpressed in both epithelial and spindle cell neoplastic components, and was negative in the giant cells. These findings permitted the diagnosis of undifferentiated carcinoma of the pancreas with osteoclast-like giant cells. This case outlines the effectiveness of endoscopic ultrasound-guided biopsy and the importance of morphological and immunohistochemical examination in the diagnosis of different types of pancreatic tumours, especially when they are in advanced stages and are not suitable for surgical treatment.

Fascitis nodular como causa de tumor lateral de cuello / Nodular fasciitis as cause of lateral neck tumor

RESUMEN La fascitis nodular es una neoplasia infrecuente y benigna que puede presentarse en los tejidos blandos de cualquier región del cuerpo y requerir tratamiento quirúrgico. Se describe aquí el caso de una mujer de 41 años con un tumor lateral de cuello que creció hasta 74,7 por 32,5 mm durante dos años. Bajo anestesia general se realizó la resección completa del tumor. El informe patológico informó una proliferación de miofibroblastos, compatible con fascitis nodular. La paciente evolucionó con un síndrome de Claude Bernard Horner homolateral, sin complicaciones locales y con una leve debilidad del brazo homolateral que recuperó luego de 60 días con kinesioterapia. Esta entidad debería ser considerada entre los diagnósticos diferenciales de un tumor lateral de cuello.

ABSTRACT Nodular fasciitis is a rare and benign neoplasm of the soft tissues that can occur in any region of the body and require surgical treatment. We report the case of a 41-year-old female patient with a lateral neck tumor which reached a size of 74.7 × 32.5 mm after two years. The tumor was completely removed under general anesthesia. The pathological examination reported proliferation of myofibroblasts, suggestive of nodular fasciitis. The patient evolved homolateral Claude Bernard Syndrome, without local complications and mild weakness of the ipsilateral arm which improved after 60 days with kinesiotherapy. This condition should be considered among the differential diagnoses of lateral neck tumors.

[Tumor size and survival in lung cancer, stage IA]. / Tamaño del tumor y supervivencia en carcinoma de pulmón, estadio 1A.

TNM staging is an important long-term predictor for survival of lung cancer patients. Some studies have shown, however, that tumor size may have intrinsic prognostic value independent of TNM stage. The relationship between tumor size and survival is particularly unclear in T1 tumors. The objective of this study was to assess the prognostic value of tumor size in surgically resected stage I of non-small cell lung cancer (NSCLC). Clinical records of 79 patients with stage IA NSCLC were reviewed. In 34.4% of patients (n = 28) size was < or = 1.5 cm. Surgical mortality was 1.3%. Disease recurrence was noted in 19%. Patients with tumors < or = 15 mm had a significantly higher 5-year survival (95% CI:0.05 vs. 77% CI: 0.07 in > 15mm group). Disease-free survival was 95% for tumors less than 15 mm vs. 72% in larger tumors. Using Cox Multivariate analysis, the most determinant factor for higher risk of mortality was size > 15 mm (relative risk 25.9, IC: 2.3-292, p = 0.004). The independent influence of tumor size in stage IA NSCLC may have practical implications with regards to proposals for screening asymptomatic individuals at high risk for lung cancer.

Timoma cervical ectópico / Ectopic cervical thymoma

RESUMEN El timoma cervical ectópico es una patología poco frecuente, motivo por el cual su diagnóstico suele ser dificultoso. Debe ser tenido en cuenta como diagnóstico diferencial en pacientes con masas cervicales laterales, sobre todo aquellas que se ubican cerca de la glándula tiroides. El tratamiento consiste en la resección quirúrgica completa. Son tumores de crecimiento lento, la mayoría de ellos histológicamente benignos. En el caso aquí presentado, por su tamaño y ubicación, fue necesario separarlo de los grandes vasos y estructuras nerviosas cercanas, lo que hizo más compleja la cirugía.

ABSTRACT Ectopic cervical thymoma is a rare entity; therefore, its diagnosis is often difficult. It should be considered as a differential diagnosis in patients with lateral cervical masses, especially those close to the thyroid gland. Surgical treatment is indicated with complete excision of the lesion. Cervical thymomas are slow-growing tumors, usually benign. In this case report, due to tumor size and location, it was necessary to separate it from the large vessels and adjacent nerve structures, resulting in a more complex procedure.

Colorectal Adenoma Risk Is Increased among Recently Diagnosed Adult Celiac Disease Patients.

BACKGROUND: The association between celiac disease and colorectal neoplasia has been previously studied, but the question whether recently diagnosed celiac patients show an increased colorectal adenoma prevalence remains unanswered. AIMS: To compare the prevalence of colorectal adenomas between adult patients with a recent diagnosis of celiac disease versus healthy controls. MATERIALS AND METHODS: A retrospective case-control study was undertaken. Patients with a diagnosis of celiac disease at an age of 45 years or more who undertook colonoscopy six months before or six months after the initiation of a gluten-free diet were enrolled as cases. Asymptomatic subjects undertaking screening colonoscopy were recruited as controls in a 2 : 1 fashion. The prevalence of colorectal adenomas and the prevalence of advanced adenomas were compared between groups. RESULTS: 57 celiac disease patients and 118 controls were enrolled. There was a greater prevalence of female patients among the celiac group, with no significant differences in terms of age. There were more obese patients among controls and a higher proportion of tabaquism among celiac patients. Adenoma prevalence was significantly higher among celiac patients (47.37% versus 27.97%, p = 0.01). Advanced adenoma detection was not different between groups. CONCLUSION: Adult patients with a recent diagnosis of celiac disease have an increased prevalence of colorectal adenomas.

[Lung biopsy for the diagnosis of interstitial lung disease]. / Biopsia en enfermedad intersticial pulmonar.

The objective of this study was to determine the morbidity, mortality and diagnostic yield of video assisted thoracoscopy (VATS) and thoracotomy lung biopsy in interstitial lung disease (ILD). Clinical records of 71 patients were retrospectively analyzed. There was no difference in mean hospital stay, intensive care unit stay and duration of chest tube drainage in patients with VATS (n = 52) compared with those undergoing open thoracotomy (n = 17). Complications rate (22.2% vs. 21.0%, p = 1.0000) and operating mortality (9.2 vs. 15.7%, p = 0.2738) were also similar. Overall, complications occurred in 16 patients (22.5%). Thirty-day mortality rate was 11.2% (n = 8). Prevalence of immunosupression (4/8 vs. 9/63, p = 0.0325) was significantly higher in the group of patients who died. No surviving patients had higher values of plasmatic urea (50 +/- 20.1 mg/dl vs. 31.2 +/- 10.3 mg/dl, p = 0.0013) or lower values of preoperative oxygen saturation (SaO2): 82.7 +/- 14.8% vs. 92.8 +/- 3.4%, (p = 0.0009). Eleven patients had an acute illness. Those patients did not show a higher complication rate (4/11 vs. 10/45, p = 0.4390) but mortality was significantly higher (4/11, 36.3% vs. 3/45, 7.1%, p = 0.0223). Biopsy allowed a specific histologic diagnosis in 100% of patients and changed therapy in 66.7%. We conclude that surgical lung biopsy is a safe and useful procedure in patients with ILD. However the higher mortality rate in patients with acute symptoms, immunocompromise, or in respiratory failure must be balanced against potential benefits of altering treatment decisions.

[BK virus nephropathy after renal transplantation. Diagnosis and prognosis by real time PCR]. / Nefropatía por virus BK post trasplante renal. Diagnóstico y seguimiento por PCR en tiempo real.

BK virus nephropathy may lead to kidney transplant failure. BK infection and acute rejection are clinically undistinguishable, therefore diagnosis of these entities is critical to establish the correct treatment. The new molecular methods using PCR and real time PCR have significantly contributed to the rapid and sensitive diagnosis of BK virus. Furthermore, viral load determination in-plasma has significantly been associated with BK virus nephropathy. Definite diagnosis of nephropathy requires renal biopsy, although due to the multifocal nature of the disease sensitivity may be less than 100%. BK detection in blood and urine by PCR has contributed to the diagnosis of nephropathy in a more standardized and less invasive way. Recently, quantification of BK virus in plasma has been used for the diagnosis and monitoring of this disease. In the present study, we describe the validation of a real time PCR method for BK virus detection in plasma and urine and its application for diagnosis and monitoring in a renal transplant patient with nephropathy.

Dual renin-angiotensin system blockade plus oral methylprednisone for the treatment of proteinuria in IgA nephropathy.

Renin-angiotensin system inhibition is a widely accepted approach to initially deal with proteinuria in IgA nephropathy, while the role of immunosuppressants remains controversial in many instances. A prospective, uncontrolled, open-label trial was undertaken in patients with biopsy-proven IgA nephropathy with proteinuria > 0.5 g/day and normal renal function to assess the efficacy of a combination treatment of angiotensin converting enzyme inhibitors plus angiotensin receptor blockers enalapril valsartan coupled with methylprednisone to decrease proteinuria to levels below 0.5 g/day. Twenty patients were included: Age 37.45 +/- 13.26 years (50% male); 7 patients (35%) were hypertensive; proteinuria 2.2 +/- 1.86 g/day; serum creatinine 1.07 +/- 0.29 mg/dl; mean follow-up 60.10 +/- 31.47 months. IgA nephropathy was subclassified according to Haas criteria. Twelve patients (60%) were class II; seven (35%) were class III and one (5%) class V. All patients received dual renin-angiotensin system blockade as tolerated. Oral methylprednisone was started at 0.5 mg/kg/day for the initial 8 weeks and subsequently tapered bi-weekly until the maintenance dose of 4 mg was reached. Oral steroids were discontinued after 24 weeks (6 months) of therapy but renin-angiotensin inhibition remained unchanged. At 10 weeks of therapy proteinuria decreased to 0.15 +/- 0.07 g/day (P < 0.001) while serum creatinine did not vary: 1.07 +/- 0.28 mg/dl (P = ns). After a mean follow-up of 42.36 +/- 21.56 months urinary protein excretion (0.12 +/- 0.06 g/day) and renal function (serum creatinine 1.06 +/- 0.27 mg/dl) remained stable. No major side effects were reported during the study. Renin-angiotensin blockade plus oral steroids proved useful to significantly decrease proteinuria to < 0.5 g/day in patients with IgA nephropathy without changes in renal function.

Glomerulonefritis por cambios mínimos post vacuna COVID-19 AstraZeneca / Glomerulonephritis due to minimal change disease post COVID-19 vaccine AstraZeneca

RESUMEN Reportamos un caso de una mujer de 28 años, con síndrome nefrótico debido a glomerulonefritis por cambios mínimos 48horas después de la administración de la vacuna contra SARS-CoV2 de AstraZeneca. La paciente tuvo síndrome nefrótico idiopático en la infancia tratado empíricamente con corticoides y ciclosporina, en remisión completa desde los 9 años. Algunos reportes sugieren que determinadas enfermedades glomerulares podrían asociarse infrecuentemente a las vacunas.

ABSTRACT We report a case of a 28-year-old woman with minimal change disease secondary nephrotic syndrome 48 hours after the administration of the AstraZeneca SARS-CoV2 vaccine. The patient had suffered idiopathic nephrotic syndrome in childhood treated empirically with corticosteroids and cyclosporine, in complete remission from the age of 9. Some reports suggest that glomerular disease might appear infrequently associated to some vaccines.

In IgA Nephropathy, Glomerulosclerosis Is Associated with Increased Urinary CD80 Excretion and Urokinase-Type Plasminogen Activator Receptor-Positive Podocyturia.

BACKGROUND: Podocyturia may determine the evolution to podocytopenia, glomerulosclerosis, and renal failure. According to the Oxford classification of IgA nephropathy (IgAN), the S1 lesion describes glomerulosclerosis. Urokinase-type plasminogen activator receptor (uPAR) participates in podocyte attachment, while CD80 increases in glomerulosclerosis. We measured uPAR-positive urinary podocytes and urinary CD80 (uCD80) in controls and in IgAN subjects with M1E0S0T0 and M1E0S1T0 Oxford scores to assess a potential association between podocyturia, inflammation, and glomerulosclerosis. METHODS: The groups were as follows: controls (G1), n = 20 and IgAN group (G2), n = 39, subdivided into M1E0S0T0 (G2A), n = 21 and M1E0S1T0 (G2B), n = 18. Among the included variables, we determined uPAR-positive podocytes/gram of urinary creatinine (gUrCr) and uCD80 ng/gUrCr. Biopsies with interstitial fibrosis and tubular atrophy <10% were included. RESULTS: Groups were not different in age and gender; urinary protein-creatinine (uP/C) ratio, Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation, uPAR-positive podocytes/gUrCr, and uCD80 were significantly increased in G2 versus G1. G2A and G2B were not different in age, gender, hypertension, and follow-up. G2B displayed significantly higher uP/C, uPAR-positive podocytes, uCD80, and lower CKD-EPI versus G2A. Strong significant correlations were encountered between uCD80 and podocyturia in G2A and G2B. However, when G1 was compared to G2A and G2B separately, the differences with respect to uP/C, uPAR-positive podocytes, and podocyturia were significantly stronger versus G2B than versus G2A. CONCLUSIONS: IgAN presents elevated uCD80 excretion and uPAR-positive podocyturia, while CD80 correlates with podocyturia. Glomerulosclerosis (S1) at the time of biopsy is associated with higher uP/C, lower renal function, increased uPAR-positive podocyturia, and CD80 excretion, and is independent of M1. In IgAN, uPAR may participate in podocyte detachment.

Multicenter study of diffuse pleural mesothelioma. histopathological and immunohistochemical features / Estudio multicéntrico de características histopatológicas e inmunohistoquímicas del mesotelioma pleural difuso

Abstract The pathological diagnosis of diffuse pleural mesothelioma (DPM) contributes to treatment selection and clinical trials interpretation. To know its characteristics and evaluate the viability of comprehensive pathological diagnosis of DPM in Argentina we did a retrospective descriptive study of DPM cases reported from 2009 to 2018. We analyzed 398 cases corresponding to 238 (60%) men and 160 (40%) women, median age 66 years, from surgical biopsies (78%), small biopsies (16.5%) and surgical resections (5.5%). The 77% were epithelioid (E-DPM), 12% biphasic, 10% sarcomatoid, and 4 cases transitional variant. In E-DPM the main pattern was tubular in 36% and solid in 33%. There was a second pattern in 179 cases. Considering the main pattern and the second together, 48% presented tubular subtype and 48% solid subtype. Stroma, necrosis, and nuclear score showed significant differences between E-DPM and non-epithelioid mesotheliomas. Overall tumor grade was predominantly low in E-DPM, except for 42% of the solid main pattern. We recognized the transitional variant extensively in 4 cases and focally in 8. The immunohistochemical antibody panel used included pan-cytokeratin, calretinin, WT-1, cytokeratin 5, CEA and TTF-1. The expression of cytokeratin 5, calretinin and WT-1 was lower in the sarcomatoid type (43%, 87 and 37%) than in the epithelioid type (92%, 98% and 93%). This study highlights the tumor heterogeneity of DPM that shows the diagnostic difficulty, and the feasibility of evaluating histological aggressiveness in E-DPM, B-DPM and S-DPM in our country.

Resumen El diagnóstico patológico del mesotelioma pleural difuso (MPD) contribuye a la selección del tratamiento y a la interpretación de los ensayos clínicos. Para conocer sus características y evaluar la viabilidad del diagnóstico patológico de MPD en Argentina se realizó un estudio descriptivo retros pectivo de los casos de MPD informados de 2009 a 2018. Se analizaron 398 casos correspondientes a 238 (60%) hombres y 160 (40%) mujeres, mediana de edad de 66 años, a partir de biopsias quirúrgicas (78%), biopsias pequeñas (16.5%) y resecciones quirúrgicas (5.5%). El 77% fue epitelioide (E-MPD), 12% bifásicos, 10% sarcomatoides y 4 casos variante transicional. En E-MPD se encontró como patrón principal el tubular en 36% y el sólido en 33%. Hubo un segundo patrón en 179 casos. Considerando el principal y el segundo patrón en conjunto, el 48% presentó subtipo tubular y el 48% subtipo sólido. El estroma, la necrosis y el score nuclear mostraron diferencias significativas entre E-MPD y mesoteliomas no epitelioides. El grado general del tumor fue predominantemente bajo en E-MPD, a excepción del 42% del patrón principal sólido. Reconocimos la variante transicional en forma extensa en 4 casos y focalmente en 8. La expresión de citoqueratina 5, calretinina y WT-1 fue menor en el tipo sarcomatoide (43%, 87 y 37%) que en el tipo epitelioide (92%, 98% y 93%). Este estudio destaca la heterogeneidad tumoral de MPD que evidencia la dificu ltad en el diagnóstico y la viabilidad de evaluar la agresividad histológica en E-MPD, B-MPD y S-MPD en nuestro país.

[Bronchioalveolar carcinoma: five year survival]. / Carcinoma broncoalveolar. Sobrevida a cinco años.

The epidemiology and prognosis of bronchioalveolar carcinoma (BAC) is different from adenocarcinoma. We studied 28 patients who underwent surgical resection and in whom a final histologic diagnosis of bronchioalveolar carcinoma was made. Sixty one percent of patients were asymptomatic at the time of diagnosis. The most usual radiological presentations were pulmonary nodule (11), pulmonary mass (6) and diffuse infiltrate (6). Nine patients (9/25) were never smokers. Bronchoscopy provided the diagnosis only in 4/26 patients. Patients were classified as stage IA 11/24, IB 5/24 IIIB in 2/24 and IV in 6/24. Five-year survival for the entire group was 65%. Patients with focal lesions had a longer survival. The survival in patients who underwent potentially curative resections was 62.8 +/- 44.0 months. When surgery was considered non-curative, survival was 21.2 +/- 19.5 months (p = 0.0064). Five-year survival in stage IA patients was 80%. Survival of patients with non-mucinous histology was longer than those with mucinous type carcinomas (54.9 +/- 25.0 months vs. 5.33 +/- 4.04, p < 0.0001) but the 5-year-survival was not statistically different. In conclusion, BAC has a favourable prognosis. The best survival rate was found in focal forms, represented by early tumor, nodes, metastasis (TNM) stages and non-mucinous BAC among the histological groups.

Valor del estudio patológico intraoperatorio de tiroides. Comparación con la punción aspiración preoperatoria y la patología diferida / Value of the intraoperative pathology in thyroid surgery: comparison with preoperative aspiration puncture and deferred pathology

Resumen Para evaluar la utilidad diagnóstica del estudio patológico intraoperatorio (EPI) en cirugía tiroidea se realizó una revisión retrospectiva de sus resultados en 350 pacientes en comparación con la biopsia preoperatoria por punción con aguja fina (PAAF) y el est udio patológico diferido (EPD). Los resultados de la PAAF se clasificaron según el sistema de Bethesda en categoría II (91 casos, 26.0%), III (21 casos, 6.0%), IV (73 casos, 21.9%), V (54 casos, 15.4%) y VI (111 casos, 31.7%). El EPI mostró lesiones benignas en 137 casos (39.1%), malignas en 169 (48.2%), y resultados no definitivos en 44 (12.6 %). El EPD informó patología benigna en 161 casos (46%) y carcinoma en 189 (54%); se encontró carcinoma en 8 pacientes (5.8%) en quienes el EPI había informado lesión benigna y en 12 (27.2%) en quienes había informado no definitivo; 13 de estos 20 casos fueron microcarcinomas incidentales. El EPI no informó ningún falso positivo (especificidad 100%, sensibilidad 89.4%, valor predictivo positivo 100%, valor predictivo negativo 90.0%, exactitud 94.2%). Los resultados de malignidad con EPI y EPD, según categorías de Bethesda fueron respectivamente: II 3 (3.3%) y 7 (7.7%); III 8 (38.1%) y 10 (47.6%); IV 3 (4.1%) y 10 (13.7%); V 47 (87.0%) y 52 (96.3%); VI 108 (97.3%) y 110 (99.1%). El EPI no dio información adicional a la biopsia por PAAF en la mayoría de los casos ni detectó microcarcinomas en otros, por lo que no parece justificado indicarlo rutinariamente.

Abstract To evaluate the usefulness of intraoperative pathology (IP) in thyroid surgery, a retrospective review of its results in 350 patients was performed in comparison with the results of the preoperative fine-needle biopsy (FNB) and the surgical pathology report (SPR). The FNB was reported according to the Bethesda system as type II in 91 cases (26.0%), type III in 21 (6.0%), type IV in 73 (21.9%), type V in 54 (15.4%), and type VI in 111 (31.7%). The IP showed benign lesions in 137 cases (39.1%), malignancy in 169 (48.2%), and inconclusive results in 44 (12.6%). The SPR results were benign pathology in 161 cases (46%) and carcinoma in 189 (54%); carcinoma was found in 8 patients (5.8%) in whom the IP had reported benignity, and in 12 (27.2%) with IP inconclusive results; 13 of those 20 cases were incidental microcarcinomas. The IP did not report any false positive result (specificity 100 %, sensitivity 89.4%, positive predictive value 100%, negative predictive value 90.0%, and accuracy 94.2%). When discriminated by Bethesda types, the malignant lesions detected by IP and SPR were, respectively: II 3 (3.3%) and 7 (7.70%); III 8 (38.1%) and 10 (47.6%); IV 3 (4.1%) and 10 (13.7%); V 47 (87.0%) and 52 (96.3%); VI 108 (97.3%) and 110 (99.1%). In most cases, the IP did not provide additional information to the FNB report nor did it detect microcarcinomas in others, so it does not seem justified to perform it routinely.