Can FDG-PET replace biopsy for the evaluation of residual tumor in pediatric mature B-cell non-Hodgkin lymphoma?

INTRODUCTION: The aim of our study is to evaluate the role of 18 F-labeled fluorodeoxy glucose positron emission tomography (18 FDG-PET) scan for the detection of viable residual mass in pediatric mature B-cell non-Hodgkin lymphoma (NHL). This study also aims to detect the negative predictive value, positive predictive value (PPV), sensitivity, and specificity of 18 FDG-PET. PATIENTS AND METHODS: A retrospective, cross-sectional nonrandomized study was carried out. We included all patients with newly diagnosed mature B-cell NHL treated at the Children Cancer Hospital Egypt during the period between July 2007 and the end of May 2018. Patients were included in the study if they (a) had a residual tumor mass, (b) underwent an 18 FDG-PET scan, and (c) had a pathologic documentation of this residual tumor. Patients were followed up till June 2019. RESULTS: Thirty-six patients were included, for whom 39 biopsies were performed. Mean age was 7.7 years. Median follow-up period was 52.8, range 6.1 to 117 months.18 FDG-PET scan was positive (Deauville score 3, 4, or 5) in 24 of 39 patients (61.5%), while it was negative (Deauville score 1 or 2) in 15 patients (38.5%). Positive 18 FDG-PET scan and biopsy were performed in 15 of 39 samples (38.4%; true positive, TP), while they were both negative in 13 samples (33.3%; true negative). Nine patients (23%) had positive scan and a negative biopsy (false positive), while 2 patients had negative uptake and a positive biopsy (false negative, FN)). Sensitivity of the 18 FDG-PET scan was 88.2% and specificity was 59.1%. PPV was 62.5% and NPPV was 86.6%. CONCLUSION: Changing therapy on the basis of a positive finding alone at the time of evaluation is not recommended. FN results exist, so biopsy confirmation is required to avoid the missing refractory disease. If negative, 18 FDG- PET can replace a biopsy if the latter is inaccessible or carries an unnecessary risk.

Langerhans Cell Histiocytosis (LCH) in Egyptian Children: Does Reactivation Affect the Outcome?

OBJECTIVE: To report a single centre outcome of management of Langerhans cell histiocytosis (LCH), a clonal disease with involvement of various body systems. METHODS: Retrospective analysis of 80 pediatric LCH patients at Children Cancer Hospital-Egypt between July 2007 and December 2011 was performed. Patients were stratified and treated according to LCH III protocol. The median follow up period was 42 mo (range: 1.18 to 71 mo). RESULTS: At wk 6 and 12, 'better' response was obtained in 61 (76 %) and 74 (93 %) patients respectively. Afterwards, reactivation occurred in 25 patients (38 %), of them multiple episodes occurred in 5 patients (6.25 %), managed by repetition of 1st line treatment for once or more. The 5 y overall survival (OS) and event free survival (EFS) was 96.3 and 55 % respectively. At last follow up, better status was reached in 70 patients, 3 in each 'intermediate' and 'worse' status. Three high risk patients died and one patient was lost to follow up. CONCLUSIONS: In a single Egyptian pediatric LCH experience, the response to treatment is satisfactory and survival remains the rule except in high risk organs disease that still needs a new molecule for salvage. However in multiple reactivations, patients do well with repetition of the 1st line of treatment with or without methotrexate.

Outcome of pediatric parameningeal rhabdomyosarcoma. The Children Cancer Hospital, Egypt, experience.

BACKGROUND: PM RMS represents a diagnostic and therapeutic problem as it is less visible than other superficial head and neck sites, and has tendency to local and intracranial extension. OBJECTIVES: The aim of this work is to study the treatment outcome, overall survival (OS) and event free survival (EFS) of pediatric PM RMS patients diagnosed and treated at the Children Cancer Hospital-Egypt [CCHE-57357] during a 4 year period. METHODS: Retrospective review of charts of newly diagnosed pediatric PM RMS patients diagnosed and treated in CCHE during the period between July 2007 and the end of June 2011. RESULTS: Forty-two pediatric patients with PM RMS with age ranging from 3 months to 17.7 years (median 6.9 years) were studied. The follow up period ranged from 4 to 55 months with a median of 24.8 months. Twenty-one patients [50%] were stage III, while 11 patients [26.1%] were stage IV. The 3-year overall survival (OS) was 58.4 ± 8.9%. OS was 65.9 ± 10% for non metastatic tumors while it was 35.8 ± 16.2% for the metastatic ones (p=0.039). The 3-year event-free survival (EFS) was 48 ± 8.6% for the whole group. The non-metastatic and metastatic patients had 3-year EFS of 56.5 ± 9.7% and 24.9 ± 14.9% respectively. This difference was not statistically significant (p=0.127). CONCLUSION: PM RMS remains a diagnostic and therapeutic problem. Late presentation and advanced local disease compromise treatment options and decrease OS and EFS.