Fat-Containing Soft Tissue Tumors in Children, Adolescents, and Young Adults: Which Require Biopsy?

PURPOSE: To confirm the overall benignity of fat-containing soft tissue tumors (STT) on a pediatric cohort and to define the clinical and imaging features that warrant a biopsy. METHODS: A retrospective monocentric study was conducted on patients aged less than 25 years consecutively referred for fat-containing STT to our Comprehensive Cancer Center between 1998 and 2022. Tumor imaging characteristics at diagnosis (US, CT, or MRI) were correlated with pathology. RESULTS: The database extraction identified 63 fat-containing tumors with clinical, histologic, and imaging data available for review. In total, 58 (92%) were benign tumors: 36 lipoblastomas and lipomas, 12 fibrous hamartomas of infancy (FHI), 5 lipofibromatosis, 2 lipomas arborescens, 2 lipomatosis and 1 spindle-cell lipoma. Five patients (8%) were diagnosed with liposarcoma. Factors significantly correlated with malignancy were age >10 years old (p < 0.001), having a cancer-predisposing condition (p < 0.001), a percentage of fat <25% (p = 0.002), and a presence of myxoid zones (p < 0.001) on imaging. CONCLUSION: Most fat-containing STT in children may be classified as benign tumors based on clinics and imaging. The indication for biopsy could be limited to patients aged 10 years or more with either a cancer-predisposing condition or imaging features demonstrating either a low-fat component (<25%) or the presence of myxoid zones.

Multicystic and diffuse malignant peritoneal mesothelioma in children.

BACKGROUND: Malignant and multicystic peritoneal mesotheliomas are extremely rare tumors in children, developing from mesothelial cells. No specific guidelines are available at this age. METHODS: We performed a retrospective analysis of all identified children (< 18-year-old) treated in France from 1987 to 2017 for a diffuse malignant peritoneal mesothelioma (DMPM) or a multicystic peritoneal mesothelioma (MCPM). RESULTS: Fourteen patients (5 males and nine females), aged 2.2 to 17.5 years, were included. The most frequent presenting symptoms were abdominal pain, ascitis, and alteration in the general condition. Eight patients had epithelioid mesothelioma, three had biphasic mesothelioma, and three had MCPM. Eight patients with DMPM diagnosis received cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Among them, six patients had neoadjuvant systemic chemotherapy, one patient, post-operative chemotherapy, and one patient CRS and HIPEC only. Three patients received only systemic chemotherapy. All patients with MCPM had only surgery. After a median follow-up of seven years (2-15), six patients (6/11; one death) with DMPM and two patients (two/three) with MCPM had a local and distant recurrences. CONCLUSION: Peritoneal mesothelioma in children is a rare condition with difficult diagnosis and high risk of recurrence. Worldwide interdisciplinary collaboration and networking are mandatory to help diagnosis and provide harmonious treatment guidelines.

[Systemic treatment for management of aggressive fibromatosis in both adult and children: Level of evidence and unsolved questions]. / Traitements systémiques des fibromatoses agressives chez l'adulte et l'enfant : niveau de preuve et questions en suspens.

We summarize here available data about systemic treatments of desmoids tumors, as well in adult patients as pediatric patients. Until 2018, the level of evidence associated with these treatments (NSAI, hormonal therapies, tyrosine kinase inhibitors, chemotherapy) was very low, based on retrospective studies or non-randomized phase 2 trials with limited number of cases. In 2018-2019, 2 large randomized trials have been published, including one large superiority phase 3 trial comparing sorafenib to placebo. This trial clearly demonstrates the clinical benefit of sorafenib over placebo (level of evidence IA). To conclude, wait-and-see policy must be the first-line approach, systemic treatment is indicated in case of disease progression. Randomized trials are feasible in this exceptional disease.

[Complementary and alternative medicine use in two French pediatric oncology centers: A common practice]. / Utilisation des médecines complémentaires et alternatives chez l'enfant et l'adolescent atteint de cancer : une pratique fréquente.

BACKGROUND: The use of complementary and alternative medicine (CAM) in children with cancer is commonly used. However, studies and data on this topic are still scarce in France. METHODS: Our aim was to investigate the prevalence of CAM usage in pediatric cancer patients and describe the modality of use. Our study population comprised children and young people treated from 2011 to 2012 in 2 French centers (Nantes, Paris). An anonymous self-administered questionnaire was addressed to families and data was collected from them and from the medical record. RESULTS: Out of the 202 patients selected for the study, 111 families answered the questionnaire (55%). Fifty-four (48.6%) of respondents reported CAM used. Forty-seven (87%) patients used CAM during initial therapy of cancer. Thirty-two (59.3%) of them talked about their CAM usage with health professionals, whose 25 (75.8%) with their oncologist. The three most common therapies used were homeopathy (75.8%), chiropractic (31.5%) and faith healing (42.6%). The main reason for the use of CAM was to control the side effects of conventional treatment (85.2%). Overall perceived satisfaction was rated 7.4/10. CONCLUSION: The prevalence of complementary and alternative medicines administration is high, even if scientific evidence is limited regarding the effects, mechanisms of action and security of CAM. Research is necessary to improve the communication and council quality to the family, optimize supportive cares and reinforce the pharmacovigilance.

Cytoreductive surgery and hyperthermic intraperitoneal perfusion with chemotherapy in children with peritoneal tumor spread: A French nationwide study over 14 years.

BACKGROUND: Efficacy and role of cytoreductive surgery (CRS) and hyperthermic peritoneal perfusion with chemotherapy (HIPEC) remain poorly documented in pediatric tumors. METHODS: This retrospective national study analyzed all pediatric patients with peritoneal tumor spread treated by CRS and HIPEC as part of a multimodal therapy in France from 2001 to 2015. RESULTS: Twenty-two patients (nine males and 13 females) were selected. The median age at diagnosis was 14.8 years (4.2-17.6). Seven had peritoneal mesotheliomas; seven, desmoplastic small round cells tumors (DSRCT); and eight, other histologic types. A complete macroscopic resection (CC-0, where CC is completeness of cytoreduction) was achieved in 16 (73%) cases. Incomplete resections were classified as CC-1 in four (18%) cases and CC-2 in two (9%) cases. Fourteen (64%) patients had complications within 30 days from HIPEC, requiring an urgent laparotomy in eight (36%) cases. Thirteen (59%) patients received adjuvant chemotherapy and four (18%) received total abdominal radiotherapy after surgery. Sixteen (72%) patients had relapse after a median time of 9.6 months (1.4-86.4) and nine (41%) eventually died after a median time of 5.3 months (0.1-36.1) from relapse. Six (27%) patients (four mesotheliomas, one pseudopapillary pancreatic tumor, and one DSRCT) were alive and in complete remission after a median follow-up of 25.0 months (5.3-78.2). The mean overall survival (OS) and disease-free survival (DFS) were 57.5 months (95% CI [38.59-76.32]) and 30.9 months (95% CI [14.96-46.77]). Patients with a peritoneal mesothelioma had a significantly better OS (p = 0.015) and DFS (p = 0.028) than other histologic type. CONCLUSIONS: In this national series, outcomes of HIPEC are encouraging for the treatment of peritoneal mesothelioma in children.

Synovial sarcoma relapses in children and adolescents: prognostic factors, treatment, and outcome.

INTRODUCTION: Twenty-five to 32% of patients with synovial sarcoma (SS) relapse after appropriate treatment, and experience a poor outcome. Patients who can be salvaged by second-line therapy need to be more clearly identified. PATIENTS AND METHODS: Data of patients treated in SFCE (Société Française des Cancers de l'Enfant) centers with an initial diagnosis of localized SS before the age of 18 years and treated from 1/1988 to 12/2008, and who experienced at least one relapse, were retrieved. After descriptive analysis, statistical analysis was performed to determine prognostic factors. RESULTS: Thirty-seven patients were identified. First relapse occurred after a median interval of 24 months and was localized in 73.0% of cases and metastatic in 24.3% of cases. Treatment of relapse consisted of new surgery in 75.7% of cases, second-line chemotherapy in 73.0% of cases and radiotherapy in 48.6% of cases. Response rate to ifosfamide-based regimens was 36.4%. Overall, 70.3% patients achieved a second complete remission. Median 5-year-event-free survival was 32.8% and 5-year overall survival was 42.1%. Factors significantly correlated with better survival were primary tumor involving the limbs, age less than 12 years at diagnosis, absence of chemotherapy or radiotherapy as initial treatment and local relapse. CONCLUSION: Despite its poor overall outcome, relapse of synovial sarcoma sometimes remains curable. Aggressive surgery, when possible, in combination with chemotherapy and radiotherapy is the recommended treatment. Ifosfamide-based regimens may remain effective in patients with relapsed SS. However, alternative therapies should be proposed in patients with poor prognostic factors.

Cytoreductive surgery associated to hyperthermic intraperitoneal chemoperfusion for desmoplastic round small cell tumor with peritoneal carcinomatosis in young patients.

PURPOSE: Desmoplastic round small cell tumor (DRSCT) is a rare intraabdominal mesenchymal tissue neoplasm in young patients and spreads through the abdominal cavity. Its prognosis is poor despite a multimodal therapy including chemotherapy, radiotherapy, and surgical cytoreduction (CS). hyperthermic intraperitoneal chemotherapy (HIPEC) is considered as an additional strategy in the treatment of peritoneal carcinomatosis; for this reason, we planned to treat selected cases of children with DRSCT using CS and HIPEC. METHODS: Peritoneal disease extension was evaluated according to Gilly classification. Surgical cytoreduction was considered as completeness of cytoreduction-0 when no macroscopic nodule was residual; HIPEC was performed according to the open technique. RESULTS: We described 3 cases: the 2 first cases were realized for palliative conditions and the last one was operated on with curative intent. There was no postoperative mortality. One patient was reoperated for a gallbladder perforation. There was no other complication related to HIPEC procedure. CONCLUSIONS: Surgical cytoreduction and HIPEC provide a local alternative approach to systemic chemotherapy in the control of microscopic peritoneal disease in DRSCT, with an acceptable morbidity, and may be considered as a potential beneficial adjuvant waiting for a more specific targeted therapy against the fusion protein.