Case 320.

HISTORY: A 7-year-old boy with a history of pleuropulmonary blastoma after resection 6 years prior and germline DICER1 mutation was being monitored by physicians at a multidisciplinary genetic predisposition clinic. He demonstrated no evidence of recurrent pleuropulmonary blastoma, and his renal US, chest radiographic, and ocular screening examination results remained normal. Per age-directed screening guidelines, he underwent thyroid US (Figs 1-3). He had no signs or symptoms of hyper- or hypothyroidism. Physical examination was notable for the absence of thyromegaly or palpable nodule. US at 12-month follow-up showed no change in size or appearance of the left lobe (not shown). However, at this time, the Thyroid Imaging Reporting and Data System (TI-RADS) classification scheme was applied to the stable left lobe finding. The findings were discussed at a multidisciplinary thyroid nodule conference, and the decision was made to bring the patient back for a short-term follow-up for limited unenhanced MRI without sedation (Fig 4). A diagnosis was made based on the follow-up imaging findings.

Case 320: Intrathyroidal Thymic Tissue.

HISTORY: A 7-year-old boy with a history of pleuropulmonary blastoma after resection 6 years prior and germline DICER1 mutation was being monitored by physicians at a multidisciplinary genetic predisposition clinic. He demonstrated no evidence of recurrent pleuropulmonary blastoma, and his renal US, chest radiographic, and ocular screening examination results remained normal. Per age-directed screening guidelines, he underwent thyroid US. He had no signs or symptoms of hyper- or hypothyroidism. Physical examination was notable for the absence of thyromegaly or palpable nodule. US at 12-month follow-up showed no change in size or appearance of the left lobe (not shown). However, at this time, the Thyroid Imaging Reporting and Data System (TI-RADS) classification scheme was applied to the stable left lobe finding. The findings were discussed at a multidisciplinary thyroid nodule conference, and the decision was made to bring the patient back for a short-term follow-up for limited unenhanced MRI without sedation. A diagnosis was made based on the follow-up imaging findings.

Imaging of pediatric abdominal soft tissue tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

This paper provides imaging recommendations for pediatric abdominal tumors that arise outside of the solid viscera. These tumors are rare in children and have been categorized in two groups: abdominal wall and peritoneal tumors (desmoid tumor and desmoplastic small round cell tumor) and tumors that arise from the gastrointestinal tract (gastrointestinal stromal tumor and gastrointestinal neuroendocrine tumor). Authors offer consensus recommendations for imaging assessment of these tumors at diagnosis, during follow-up, and when off-therapy.

Imaging of pediatric extremity soft tissue tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

Pediatric soft tissue tumors of the extremity include rhabdomyosarcoma and nonrhabdomyosarcoma neoplasms. This manuscript provides consensus-based imaging recommendations for imaging evaluation at diagnosis, during treatment, and following completion of therapy for patients with a soft tissue tumor of the extremity.

Performance of Tumor Surveillance for Children With Cancer Predisposition.

Importance: Pediatric oncology patients are increasingly recognized as having an underlying cancer predisposition syndrome (CPS). Surveillance is often recommended to detect new tumors at their earliest and most curable stages. Data on the effectiveness and outcomes of surveillance for children with CPS are limited. Objective: To evaluate the performance of surveillance across a wide spectrum of CPSs. Design, Setting, and Participants: This cohort study reviewed surveillance outcomes for children and young adults from birth to age 23 years with a clinical and/or molecular CPS diagnosis from January 1, 2009, through September 31, 2021. Patients were monitored using standard surveillance regimens for their corresponding CPS at a specialty pediatric oncology center. Patients with hereditary retinoblastoma and bone marrow failure syndromes were excluded. Data were analyzed between August 1, 2021, and December 6, 2023. Exposure: Cancer predisposition syndrome. Main Outcomes and Measures: Outcomes of surveillance were reviewed to evaluate the incidence, spectrum, and clinical course of newly detected tumors. Surveillance modalities were classified for accuracy and assessed for common strengths and weaknesses. Results: A total of 274 children and young adults (mean age, 8 years [range, birth to 23 years]; 144 female [52.6%]) with 35 different CPSs were included, with a median follow-up of 3 years (range, 1 month to 12 years). During the study period, 35 asymptomatic tumors were detected in 27 patients through surveillance (9.9% of the cohort), while 5 symptomatic tumors were detected in 5 patients (1.8% of the cohort) outside of surveillance, 2 of whom also had tumors detected through surveillance. Ten of the 35 tumors (28.6%) were identified on first surveillance imaging. Malignant solid and brain tumors identified through surveillance were more often localized (20 of 24 [83.3%]) than similar tumors detected before CPS diagnosis (71 of 125 [56.8%]; P < .001). Of the 24 tumors identified through surveillance and surgically resected, 17 (70.8%) had completely negative margins. When analyzed across all imaging modalities, the sensitivity (96.4%), specificity (99.6%), positive predictive value (94.3%), and negative predictive value (99.6%) of surveillance were high, with few false-positive (6 [0.4%]) or false-negative (5 [0.3%]) findings. Conclusions and Relevance: These findings suggest that standardized surveillance enables early detection of new tumors across a wide spectrum of CPSs, allowing for complete surgical resection and successful treatment in the majority of patients.