Unresectable thoracic neuroblastic tumors: Changes in image-defined risk factors after chemotherapy and impact on surgical management

Thoracoscopy for Pediatric Thoracic Neurogenic Tumors-A European Multi-Center Study

OBJECTIVES

To assess the efficacy of thoracoscopy and the outcome for children with thoracic neurogenic tumors.

METHODS

We performed a retrospective review of 15 European centers between 2000 and 2020 with patients who underwent thoracoscopy for a neurogenic mediastinal tumor. We assessed preoperative data, complications, and outcomes. Results were expressed with the median and range values.

RESULTS

We identified 119 patients with a median age of 4 years old (3 months-17 years). The diameter was 5.7 cm (1.1-15). INRG stage was L1 n = 46, L2 n = 56, MS n = 5, M n = 12. Of 69 patients with image-defined risk factors (IDRF), 29 had only (T9-T12) locations. Twenty-three out of 34 patients with preoperative chemotherapy had an 18 mm (7-24) decrease in diameter. Seven out of 31 patients lost their IDRF after chemotherapy. Fourteen had a conversion to thoracotomy. The length of the hospital stay was 4 days (0-46). The main complications included chylothorax (n = 7) and pneumothorax (n = 5). Long-term complications included Horner's syndrome (n = 5), back pain, and scoliosis (n = 5). Pathology was 53 neuroblastomas, 36 ganglioneuromas, and 30 ganglioneuroblastomas. Fourteen had a postoperative residue. With a median follow-up of 21 months (4-195), 9 patients had a recurrence, and 5 died of disease. Relapses were associated with tumor biology, histology, and the need for chemotherapy (p = 0.034, <0.001, and 0.015, respectively). Residues were associated with preoperative IDRF (excluding T9-T12 only) and the need for preoperative chemotherapy (p = 0.04 and 0.020).

CONCLUSION

Our results show that thoracoscopy is safe, with good outcomes for thoracic neurogenic tumors in selected cases. Surgical outcomes are related to the IDRFs, whereas oncologic outcomes are related to tumor histology and biology.

Minimally invasive approach of paediatric neuroblastoma with thoracic vascular encasement

ABSTRACT

Neuroblastoma (NB) is the most frequent paediatric extracranial solid tumour. The surgical management of these tumours in newborns changed recently, performing resections in cases with tumour size increase after birth. Minimally invasive procedures were mostly reported in cases without pre-operative image-defined risk factors (IDRFs), defined by vascular and organ involvement. Thoracoscopic resection represents a minority of the overall surgical procedures for neuroblastic tumour management, as the posterior mediastinum is one of the least frequent locations of NB. A thoracoscopic resection was performed on a 22-month-old child with a NB encasing the aorta and a 6-month-old child with the encasement of the left subclavian and vertebral artery. A step-by-step minimally invasive procedure was described, highlighting anatomical landmarks and dissection techniques. The described technique was performed in 130 min. Thoracoscopic resection provided a macroscopic resection without surgical complications and patient was discharged on the 3rd post-operative day. The study shows a feasible and safe thoracoscopic approach for paediatric thoracic NB with IDRFs.

Beyond image defined risk factors (IDRFs): a delphi survey highlighting definition of the surgical complexity index (SCI) in neuroblastoma

PURPOSE

Preoperative evaluation of Image Defined Risk Factors (IDRFs) in neuroblastoma (NB) is crucial for determining suitability for upfront resection or tumor biopsy. IDRFs do not all carry the same weighting in predicting tumor complexity and surgical risk. In this study we aimed to assess and categorize a surgical complexity (Surgical Complexity Index, SCI) in NB resection.

METHODS

A panel of 15 surgeons was involved in an electronic Delphi consensus survey to identify and score a set of shared items predictive and/or indicative of surgical complexity, including the number of preoperative IDRFs. A shared agreement included the achievement of at least 75% consensus focused on a single or two close risk categories.

RESULTS

After 3 Delphi rounds, agreement was established on 25/27 items (92.6%). A severity score was established for each item ranging from 0 to 3 with an overall SCI range varying from a minimum score of zero to a maximum score of 29 points for any given patient.

CONCLUSIONS

A consensus on a SCI to stratify the risks related to neuroblastoma tumor resection was established by the panel experts. This index will now be deployed to critically assign a better severity score to IDRFs involved in NB surgery.

Contrast-enhanced computed tomography radiomics in predicting primary site response to neoadjuvant chemotherapy in high-risk neuroblastoma

PURPOSE

To explore the clinical value of contrast-enhanced computed tomography (CECT) radiomics in predicting primary site response to neoadjuvant chemotherapy in high-risk neuroblastoma.

MATERIALS AND METHODS

Seventy patients were retrospectively included and separated into very good partial response (VGPR) group and non-VGPR group according to the changes in primary tumor volume. The clinical features with statistical difference between the two groups were used to construct the clinical models using a logistic regression (LR) algorithm. The radiomics models based on different radiomics features selected by Kruskal-Wallis (KW) test and recursive feature elimination (RFE) were established using support vector machine (SVM) and LR algorithms. The radiomics score (Radscore) and clinical features were integrated into the combined models. Leave-one-out cross-validation (LOOCV) was used to validate the predictive performance of models in the entire dataset.

RESULTS

The optimal clinical model achieved an area under the curve (AUC) of 0.767 [95% confidence interval (CI): 0.638, 0.896] and an accuracy of 0.771 after LOOCV. The AUCs of the best KW + SVM, KW + LR, RFE + SVM, and RFE + LR radiomics models were 0.816, 0.826, 0.853, and 0.850, respectively, and the corresponding AUCs after LOOCV were 0.780, 0.785, 0.755, and 0.772, respectively. The AUC and accuracy after LOOCV of the optimal combined model was 0.804 (95% CI: 0.694, 0.915) and 0.814, respectively. The Delong test showed a statistical difference in predictive performance between the optimal clinical and combined models after LOOCV (Z = 2.003, P = 0.045). The decision curve analysis showed that the combined model performs better than the clinical model.

CONCLUSION

The CECT radiomics models have a favorable predictive performance in predicting VGPR of high-risk neuroblastoma to neoadjuvant chemotherapy. When integrating radiomics features and clinical features, the predictive performance of the combined models can be further improved.

Changes in image-defined risk factors with neoadjuvant chemotherapy in pediatric abdominal neuroblastoma

PURPOSE

To observe the changes in image-defined risk factors (IDRFs) with neoadjuvant chemotherapy in pediatric abdominal neuroblastoma and to investigate the correlations between IDRF changes and histopathological features. In addition, this study also investigated the correlations between residual IDRFs after neoadjuvant chemotherapy and intraoperative complications.

METHODS

Forty-three patients with abdominal neuroblastoma who received neoadjuvant chemotherapy in our hospital from January 2015 to September 2021 were enrolled. Intraoperative records, histopathological features, and CT images at initial diagnosis and after neoadjuvant chemotherapy of all patients were retrospectively collected and analyzed.

RESULTS

A total of 245 IDRFs were found at initial diagnosis, with a median of 6 [5, 7] IDRFs per patient. After neoadjuvant chemotherapy, IDRFs significantly decreased to 156 (p < 0.001), with a median of 4 [3, 5] IDRFs remaining per patient. The majority of IDRFs (6/8, 75.00%) were significantly improved after neoadjuvant chemotherapy (p < 0.05), while tumor invasion of renal pedicles (p > 0.05) and adjacent structures (p > 0.05) was the least responsive IDRF. IDRFs in different types of neuroblastoma decreased significantly after neoadjuvant chemotherapy (p < 0.05), while they were not significant in neuroblastoma with low and intermediate mitosis-karyorrhexis indices (p > 0.05). The number of residual IDRFs correlated positively with the volumes of intraoperative blood loss (r = 0.399, p = 0.008), but not with the presence of intraoperative complications (r = 0.111, p = 0.478).

CONCLUSIONS

IDRFs in different types of neuroblastoma can be significantly improved after neoadjuvant chemotherapy, while IDRFs in neuroblastoma with low and intermediate mitosis-karyorrhexis indices might not be easily improved. At the same time, the number of residual IDRFs after neoadjuvant chemotherapy might not correlate with the occurrence of intraoperative complications in abdominal neuroblastoma.