Inflammatory pseudotumor and myofibroblastic inflammatory tumor. Diagnostic criteria and prognostic differences. / Seudotumor inflamatorio y tumor miofibroblástico inflamatorio. Criterios diagnósticos y diferencias pronósticas.

INTRODUCTION: Inflammatory pseudotumor (IPT) and inflammatory myofibroblastic tumor (IMT) are two very rare entities that were formerly included in the same category; however, today they are considered two different diseases due to the neoplastic origin of the IMT. Our objective is to share our experience in the management of these two types of tumors that we must take into account in the differential diagnosis of pulmonary masses or nodules. METHODS: Thirteen patients with a pathological diagnosis of IPT and IMT who underwent surgery between 2008 and 2019 were retrospectively studied. We recorded the pre and postoperative information of each one, as well as the survival analysis. RESULTS: Of the 13 patients, 8 were men and 5 women. The mean age of presentation was 53,5 years. An atypical segmentectomy was performed in 6 patients; a lobectomy was necessary in 6 and a pneumonectomy in 1 case. In all cases a complete resection was achieved. Diagnosis was possible thanks to histology, immunohistochemical (IHQ) and fluorescent in situ hybridization (FISH) techniques determining the expression of IgG4 and the rearrangement of ALK, respectively. After a median follow up of 49 months, we didnt find any loco-regional or distant recurrence in the patients studied. CONCLUSION: IPT and IMT are rare tumors with a very good prognostic. The diagnosis of both entities is based mainly on specific anatomopathological techniques. Surgery has, in most cases, both a diagnostic and therapeutic role.

Deciduosis peritoneal difusa simulando un mesotelioma deciduoide en una paciente primigrávida / Diffuse peritoneal deciduosis mimicking deciduoid mesothelioma in a primigravida patient

Paciente de 36 años, primigesta, con gestación de 37 semanas y sin antecedentes de interés, a la que se le practica una cesárea por fracaso de inducción. Tras realizar la laparotomía, se objetivan múltiples nódulos firmes y blanquecinos, de manera diseminada por toda la cavidad abdominal, de tamaños comprendidos entre 0,2-0,5cm. Con sospecha clínica de carcinomatosis peritoneal, se realizan biopsias de ovario, vejiga, epiplón y apéndice epiploico. Tras la intervención, se realiza TAC toraco-abdomino-pélvico, que es informado como hallazgos en relación con carcinomatosis y ascitis. El estudio morfológico e inmunohistoquímico apoyó el diagnóstico de deciduosis peritoneal difusa. Presentamos un caso poco frecuente y muy exhuberante de deciduosis peritoneal. Cuando es difusa, es importante realizar el diagnóstico diferencial, principalmente con metástasis tumorales y el mesotelioma deciduoide, ya que a diferencia de estas entidades, la deciduosis peritoneal difusa es un proceso que suele evolucionar a la regresión espontánea tras el parto (AU)

We report a case of rare, florid peritoneal deciduosis in a 36 year old patient who underwent a caesarean section at the 37th week of her first pregnancy after labour induction failed. She had an unremarkable previous medical history. On laparotomy, multiple firm, whitish nodules measuring between 0.2 and 0.5cm were seen in the abdominal cavity. As peritoneal carcinomatosis was suspected, biopsies were taken of ovaries, bladder, omentum and appendix. A thoraco-abdominopelvic CT scan was performed postoperatively which showed abdominal-peritoneal involvement and ascites. Histopathology and immunohistochemistry confirmed a diagnosis of diffuse peritoneal deciduosis. Diffuse peritoneal deciduosis must be carefully differentiated from tumour metastases and deciduoid mesothelioma as it usually regresses spontaneously after delivery (AU)