Tonsillectomy Outcomes in Children After Solid-Organ Transplantation: A 15-Year Single-Center Experience.

OBJECTIVE: Solid-organ transplantation (SOT) has become the standard of care for children with terminal organ failure. Long-term immunosuppression has improved survival substantially but is associated with secondary malignancies and impaired wound healing. Our goal was to review the incidence, outcomes, complications, and rate of posttransplant lymphoproliferative disorder on pathologic examination following tonsillectomy/adenotonsillectomy (T/AT) in children after SOT. STUDY DESIGN: A retrospective cohort study. SETTING: Tertiary care children's hospital. METHODS: Data were extracted from charts of children with a history of kidney, heart, or liver transplantation, who underwent T/AT between 2006 and 2021. RESULTS: A total of 110 patients met the inclusion criteria, including 46 hearts, 41 kidneys, 19 livers, and 4 liver-and-kidney transplants. The mean age at transplantation was 4.2 years, and the mean transplantation-to-T/AT time interval was 28.8 months. The posttransplant lymphoproliferative disorder was diagnosed in 52 (47.3%) patients, and 25% of these had no tonsillar hypertrophy. There was no difference in age at transplantation, organ received, transplantation-to-T/AT time interval, immunosuppressive medications, tonsil size, or tonsillar asymmetry between patients diagnosed with the posttransplant lymphoproliferative disorder and patients with benign tonsillar/adenotonsillar hypertrophy. Posttonsillectomy complications were similar between the groups. CONCLUSION: The incidence of posttransplant lymphoproliferative disorder undergoing tonsillectomy for any indication was 47.3%. There was no association between preoperative signs and symptoms and the histopathological diagnosis of posttransplant lymphoproliferative disorder. Stratification by organ received and immunosuppressive medications did not identify differences among the groups relative to the incidence of posttransplant lymphoproliferative disorder and other postoperative complications.

Cytology-histology correlation of myoepithelial tumors harboring EWSR1-POU5F1 fusions: A report of two cases.

Myoepithelial tumors (MET) constitute a group of neoplasms with a variety of morphologic, immunophenotypic, and molecular features. Approximately half of MET of soft tissue harbor EWSR1 gene rearrangements with a subset showing EWSR1-POU5F1 fusions and demonstrating distinctive tendency towards aggressive behavior in children. Histologically, EWSR1-POU5F1-positive MET typically show clear-cell morphology with malignant features including marked pleomorphism and atypical mitotic figures. The cytomorphology of these tumors has not been well characterized. Reported here are the cytomorphologic features of two cases of EWSR1-POUF1-positive MET with histology correlation.

p53 and ß-Catenin Expression Predict Poorer Prognosis in Patients With Anaplastic Large-Cell Lymphoma.

BACKGROUND: The Wnt/ß-catenin signaling pathway is a major target of p53. ß-Catenin/p53 coexpression predicts poorer survival in carcinoma patients. Conversely, CD99 inhibits tumor metastasis through the Wnt/ß-catenin pathway. We therefore assessed p53, ß-catenin, and CD99 by immunohistochemistry. PATIENTS AND METHODS: We studied 45 patients with systemic anaplastic large-cell lymphoma (ALCL), including 20 anaplastic lymphoma kinase (ALK)-positive and 25 ALK-negative ALCL. ß-Catenin expression was analyzed using phospho-ß-catenin-S552 antibody because its nuclear localization indicates Wnt signaling. RESULTS: In this cohort, p53 expression was associated with ALK-negative ALCL. Furthermore, p53 or ß-catenin expression alone or ß-catenin/p53 double expression showed poorer overall survival and disease-free survival in patients with ALCL overall and in patients with ALK-negative ALCL. CD99 expression was more frequent in ALK-positive ALCL but had no prognostic significance. CONCLUSION: This is the first study to evaluate phospho-ß-catenin-S552 expression in ALCL. The results of this study, although limited by small patient size, suggest that ß-catenin and p53 may play a role in pathogenesis and may be helpful in risk stratification of ALCL patients.

p53 expression in large B-cell lymphomas with MYC extra copies and CD99 expression in large B-cell lymphomas in relation to MYC status.

p53 expression and MYC extra copies (MYC-EC) have been reported to serve as independent adverse prognostic markers in patients with diffuse large B-cell lymphoma (DLBCL). However, the impact of p53 expression in MYC-EC lymphomas has not been delineated. Conversely, CD99 expression has been shown to have a positive impact on survival in patients with germinal center-type DLBCL, yet nothing is reported about the impact of CD99 expression and MYC status. This is the first study to evaluate p53 expression in MYC-EC lymphomas and CD99 expression in relation to MYC status. We identified 122 patients diagnosed as having large B-cell lymphoma (44, MYC-negative; 29, MYC-EC; 23, MYC rearrangement; 22, MYC and BCL2 rearrangements; 4, MYC, BCL2, and BCL6 rearrangements). p53 expression significantly correlated with DLBCL with abnormal MYC status (MYC-EC, MYC rearrangement, and MYC overexpression), but adverse p53 prognostic effect was only seen with MYC-rearranged lymphoma. CD99 expression was significantly associated with MYC-negative DLBCL and had better prognostic impact on lymphoma-specific survival (LSS), but not on relapse-free survival and overall survival. Overall, patients with MYC-EC lymphoma had significantly worse relapse-free survival and LSS than did patients with MYC-negative lymphoma, yet better overall survival and LSS than did the patients with MYC-rearranged lymphoma. Thus, patients with MYC-EC lymphomas had prognostic features that were intermediate between MYC-negative and MYC-rearranged lymphomas. Lastly, high-intensity chemotherapy (either dose-adjusted rituximab and etoposide-prednisone-vincristine-cyclophosphamide-doxorubicin or rituximab and hyperfractionated cyclophosphamide-vincristine-doxorubicin-dexamethasone treatment) did not improve survival in patients with MYC-EC and MYC-rearranged lymphoma when compared with rituximab-cyclophosphamide-hydroxydaunomycin-vincristine-prednisone therapy.

Gastrointestinal Stromal Tumor Induced Hypercalcemia.

Hypercalcemia in patients with cancer is a common laboratory finding affecting up to 44% of that patient population. 1,25-Dihydroxyvitamin D3 mediated hypercalcemia is one of the rare mechanisms of this endocrine emergency in cancer patients. It is even rarer for solid organ neoplasms to present with hypercalcemia mediated through the production of 1,25-dihydroxyvitamin D3. We report a case of a 77-year-old female who presented to the hospital with hypercalcemia and later was found to have metastatic gastrointestinal stromal tumor. There have been only 5 cases of gastrointestinal stromal tumor described in literature resulting in hypercalcemia. In our case, the mechanism of hypercalcemia was thought to be related to overproduction of 1,25-dihydroxyvitamin by tumor cells. The patient had a favorable response to imatinib with normalization of serum calcium level. Unfortunately, she developed fluid retention due to imatinib which was discontinued resulting in relapse of hypercalcemia that was resistant to all other treatment options.