Abdominal plasma cell pseudotumor*

Inflammatory pulmonary (PPT) and extrapulmonary pseudotumors (EPPT) are uncommon benign tumors, which, in general, do not recur after complete resection. Recurrence rates for both types of pseudotumors are undocumented in a large population of children, and the salient features of potential recurrences are unspecified.

This is a report of 15 children with PPT and EPPT; 3 children had a recurrence. These pseudotumors recurred despite adequate primary resection of all gross disease at first presentation. The literature was reviewed to determine rate of recurrence for PPT and EPPT and also to document features common to recurrent pseudotumors.

Overall recurrence rate for pseudotumors was 14%. PPT and EPPT, which were not confined to a single organ, had a high chance of recurrence (46% and 30%, respectively) compared with PPT and EPPT, which were confined to a single organ (1.5% and 8%, respectively). Recurrences have appeared between 3 months and 7 years. Intraabdominal EPPT accounts for more than 75% of the EPPT recurrences.

PPT and EPPT recur more frequently than anticipated. All pseudotumors, which on initial presentation extend beyond the confines of a single organ, have a high chance of recurrence despite what appears to be adequate resection. Children with pseudotumors that extend beyond a single organ, require frequent postoperative evaluation for recurrence and may be candidates for chemotherapy or radiotherapy at the time of initial resection.

Inflammatory myofibroblastic tumor is a rare gastrointestinal neoplasm. The authors report the case of a 5-year-old girl who initially presented with gastric outlet obstruction secondary to an inflammatory myofibroblastic tumor along the lesser gastric curvature. A subtotal gastrectomy and wedge resection of a left hepatic lobe nodule were performed. Obstructive jaundice developed one month postoperatively. Computerized tomography, percutaneous transhepatic cholangiography, and selective celiac and mesenteric arteriography showed a mass that involved the left hepatic lobe, with concomitant high-grade biliary obstruction and portal venous encasement. Percutaneous biliary drainage was performed. During laparotomy, the tumor was found to be unresectable, and the patient was referred to the Liver Transplant Service at The Children's Hospital of Philadelphia. A total hepatectomy with temporary portocaval shunt was performed, leaving the inferior vena cava in situ. At the back table, an ex vivo left trisegmentectomy was performed, followed by reimplantation of the posterior segment of the right hepatic lobe. The reimplanted liver segment functioned poorly, and completion hepatectomy with portocaval shunt was performed 24 hours postoperatively, because of severe coagulopathy, intraabdominal bleeding, and hemodynamic instability. The patient's condition stabilized, and she was listed for urgent liver transplantation. The anhepatic state was managed with intermittent plasmapheresis. She had transplantation 72 hours later, and was discharged from the hospital 3 weeks postoperatively after an uneventful recovery. She remains disease-free and has normal liver function 8 months after transplantation.

An unusual case of inflammatory pseudotumor of the subcutaneous tissue in a 44-yr old black male who presented with a 4 cm soft tissue mass on the dorsum of right hand is described. The mass was sharply circumscribed and composed of a polymorphous infiltrate of plasma cells, eosinophils, lymphocytes and some giant cells mimicking Reed-Sternberg cells. The giant cells, corresponding ultrastructurally to primitive mesenchymal cells, were immunoreactive for vimentin and were negative for actin, desmin and histiocytic markers. The patient remained well with no sign of recurrence 8 rnths postoperatively. The present case is compared with the (4) previously reported cases in literature. The histologic differentiation from other neoplastic and non-neoplastic lesions is discussed.