Use of radiotracer labeling of pulmonary nodules to facilitate excisional biopsy and metastasectomy in children with solid tumors

The problematic PET: Using CT albumin tracer to resect suspicious lymph nodes found on PET scan in pediatric oncology patients

BACKGROUND

Management of small lymph nodes or lesions in dense nodal basins found on Positron Emission Tomography (PET) scans can be challenging to identify, access and locate intraoperatively. Herein we describe the first reported case series utilizing pre-operative CT-guided radionuclide-tagged macro-aggregated albumin (TC 99m MAA) for localization and resection of extra-pulmonary PET-avid lymph nodes in pediatric cancer patients.

METHODS

Pediatric cancer patients (≤21 years) who underwent pre-operative TC 99m MAA localization of suspicious lymph nodes were identified and retrospectively reviewed.

RESULTS

Ten procedures were performed on 10 children at our institution from 2017 to 2021. Median age was 14 [13, 18]; 70% were male. Primary tumor type was variable. Lymph nodes were in various nodal basins including the axilla, groin, neck, popliteal fossa, retroperitoneum, and mediastinum. Three patients underwent resection of both pulmonary and extra-pulmonary lesions during the same procedure. Median node size was 15 mm (range: 10 mm- 23 cm). In 60.0% of patients the localized lymph nodes of concern were non-palpable at the time of operation. In 90% of the patient, biopsy findings changed the course of disease management.

CONCLUSION

Pre-operative labeling with TC 99m MAA is a safe and effective technique to facilitate the localization, biopsy, and resection of suspicious lymph nodes found on PET scans in pediatric cancer patients that are located in dense nodal basins. This technique enables accurate resection of small, concerning lymph nodes that might otherwise be difficult to operatively identify and excise; the resultant information can affect the staging and further treatment of these patients.

LEVEL OF EVIDENCE

IV.

Interhospital variability in localization techniques for small pulmonary nodules in children: A pediatric surgical oncology research collaborative study

BACKGROUND

Pulmonary nodules that are deep within lung parenchyma and/or small in size can be challenging to localize for biopsy. This study describes current trends in performance of image-guided localization techniques for pulmonary nodules in pediatric patients.

METHODS

A retrospective review was performed on patients < 21 years of age undergoing localization of pulmonary nodules at 15 institutions. Localization and resection success, time in interventional radiology (IR), operating room (OR) and total anesthesia time, complications, and technical problems were compared between techniques.

RESULTS

225 patients were included with an average of 1.3 lesions (range 1-5). Median nodule size and depth were 4 mm (range 0-30) and 5.4 mm (0-61), respectively. The most common localization techniques were: wire + methylene blue dye (MBD) (28%), MBD only (25%), wire only (14%), technetium-99 only (11%), coil + MBD (7%) and coil only (5%). Localization technique was associated with institution (p < 0.01); technique and institution were significantly associated with mean IR, OR, and anesthesia time (all p < 0.05). Comparing techniques, there was no difference in successful IR localization (range 92-100%, p = 0.75), successful resection (94-100%, p = 0.98), IR technical problems (p = 0.22), or operative complications (p = 0.16).

CONCLUSIONS

Many IR localization techniques for small pulmonary nodules in children can be successful, but there is wide variability in application by institution and in procedure time.

LEVEL OF EVIDENCE

Retrospective review, Level 3.

Pulmonary Metastasectomy in Pediatric Patients: A Comparison of Open and Thoracoscopic Approaches

Background: Although the use of video-assisted thoracoscopic surgery (VATS) for resection of lung metastases has increased, surgeons still advocate for open resection as it permits palpation of lesions that may be missed on imaging. This study aimed to compare the utilization of open thoracotomy versus VATS over time and determine if the use of VATS changes perioperative outcomes. Methods: Using the Kids' Inpatient Database (2006, 2009, 2012, 2016), we identified children (age ≤20) with a diagnosis of secondary lung cancer with either lobectomy or sublobar resection coded during the same admission. Utilization was compared across years for the overall cohort and for patients with primary bone and connective tissue (PBCT) cancers. We defined prolonged length of stay (LOS) as LOS ≥75th percentile (LOS ≥7 days). Univariable and multivariable analyses compared in-hospital complication rates and LOS for open and VATS approaches. Results: Of the 1316 children (539 female) undergoing pulmonary resection, VATS was utilized in 374 (28.4%). Utilization increased rapidly from 2006 to 2009 (P < .001 for trend), but stabilized thereafter (P = .622). Metastatic PBCT cancers were the most common indication for resection (n = 496, 38%), but open and VATS approaches were used nearly equally (P = .368). Overall, 352 (26%) patients had complications. On multivariable analysis, the open approach remained independently associated with increased complications (odds ratio [OR] 1.48, 95% confidence interval [CI] [1.04-2.11]). Median LOS increased for open cases (5 versus 3 days, P < .001). Furthermore, open metastasectomy was associated with prolonged LOS (OR 1.50, [1.07-2.10]) after controlling for age, sex, primary cancer, reporting year, resection extent, obesity, complications, and nonoperative intubation. Conclusion: VATS approach to pulmonary metastasectomy resulted in fewer complications and shorter LOS in a nationwide sample of children. Despite these advantages, the use of VATS has plateaued. While this study cannot comment on oncologic safety or long-term outcomes, future studies should evaluate whether indications for VATS pulmonary metastasectomy can be expanded.

Microcoil localization as an effective adjunct to thoracoscopic resection of pulmonary nodules in children

BACKGROUND/PURPOSE

Thoracoscopic excision of pulmonary nodules is often required for diagnostic or therapeutic purposes, however subpleural and sub-centimeter nodules can be difficult to visualize. Various CT-guided localization techniques have been described, though there is minimal published pediatric data regarding the use of microcoils. We hypothesize that microcoil localization facilitates thoracoscopic resection of pulmonary nodules in children.

METHODS

A multi-institutional retrospective review of children who underwent preoperative CT-guided localization of lung nodules was conducted from 2012 to 2019. A combination of methylene blue dye (MBD), wires, and microcoils were utilized for CT-guided localization. When microcoils were utilized, fluoroscopy assisted in lesion identification and resection.

RESULTS

Eighteen patients (mean age 13 years, range 2-21 years) underwent thoracoscopic resection of 24 preoperatively localized pulmonary nodules. Mean size and depth of the lesions were 5.5 mm and 10 mm, respectively. Microcoil placement was successful 95% of the time and assisted in lesion localization in 88% of cases. Wire localization was not a durable technique, as 3 of 5 wires became dislodged upon lung  isolation.

CONCLUSIONS

Preoperative CT-guided localization with microcoils can assist in fluoroscopic-guided resection of pulmonary nodules in children. This technique avoids the pitfall of wire dislodgement, and provides surgeons an additional technique to localize sub-centimeter, subpleural nodules.

TYPE OF STUDY

Retrospective Review.

LEVEL OF EVIDENCE

Level III.

Surgical management of locally-advanced and metastatic hepatoblastoma

Advanced stage hepatoblastoma, including both locally advanced primary tumors as well as metastatic disease, poses unique clinical challenges. Despite substantial advances in chemotherapeutics, surgical extirpation remains the mainstay of cure for this tumor. Locally advanced tumors that involve multiple hepatic lobes and/or invade significant vascular structures can be managed either by complex hepatic resections or liver transplantation. We review the indications, roles, and outcomes of these surgical approaches as well as those for the resection of pulmonary metastases.

Minimally Invasive Surgery in Pediatric Surgical Oncology: Practice Evolution at a Contemporary Single-Center Institution and a Guideline Proposal for a Randomized Controlled Study

Background: Despite the lack of randomized or controlled trials for minimally invasive surgery (MIS) in pediatric surgical oncology, the integration of MIS into the surgical practice of pediatric oncology has become increasingly popular. The aim of this study was to evaluate the implementation of MIS in a pediatric tertiary cancer center and compare present use of MIS to that in a previous analysis at our center. Methods: We retrospectively reviewed the medical records of patients with pediatric cancer treated with MIS at a single institution between 2000 and 2014. Results: A total of 252 MIS procedures were performed: 73 laparoscopic (29%) and 179 thoracoscopic (71%). MIS was used for diagnostic purposes in 59% (146 thoracoscopic and 34 laparoscopic) and the therapeutic resection in 24% (39 laparoscopic cases and 33 thoracoscopic cases). Conversion to an open procedure occurred in 18 tumor resections (6%) and in 22 diagnostic biopsies (7%), mostly due to technical challenges in identifying or mobilizing tumors. Complications occurred in seven tumor resections (2%) and included three pneumothoraces, two bleeding complications, one bowel injury, and one wound infection. Complications occurred in 10 diagnostic biopsies (3%), mostly pneumothoraces. No tumor upstaging or trocar site recurrences occurred (follow-up time, 1-15 years). Conclusions: Over the last decade, we demonstrate the evolution of MIS in the management of solid tumors in children. We encourage surgeons and oncologists to join the call to arms to establish prospective trials evaluating MIS in pediatric surgical oncology.

Computed Tomography-Guided Wire-Marking for Thoracoscopic Resection of Small Lung Nodules in Children

Introduction: In pediatric patients, thoracoscopic wedge-resection of pulmonary nodules is an established therapy. However, intraoperative localization of small lesions is still challenging. Purpose of this study was to evaluate the efficacy of preoperative computed tomography (CT)-guided wire-marking of small lung nodules. Materials and Methods: Between 2012 and 2017 a total of six cases receiving thoracoscopic resection of CT-marked lung nodules were analyzed. The nodules were preoperatively tagged by a wire, which was attached to the thoracic wall by sterile dressing. Characteristics of interest were stability of wire, complete resection, and prevention of open thoracotomy. Results: Six procedures were performed on five patients, including four men and one woman. Median age at intervention was 16 years (range 11-19 years). All patients had a history of primary malignancies, including osteosarcoma (n = 4) and synovial sarcoma (n = 1). A total of 10 nodules were visualized in CT of which 9 were marked by wire. The median expected size of nodules was 6 mm (range 2-23 mm). Two patients had bilateral, two left-sided and two right-sided lung lesions. There was no wire slippage. In five procedures wedge resection was possible; one case needed a near total lobe resection. In one case a mini-thoracotomy at port insertion site was performed to extract the specimen. There was no conversion to thoracotomy. Histopathology showed R0 resection in all patients. Malignancy was found in all specimens. In one patient postoperative hemorrhagic anemia necessitated transfusion. Conclusions: Preoperative wire-localization of small lung nodules is a safe and effective tool to enable thoracoscopic resection in children and to avoid thoracotomic interventions.

Pulmonary Metastasectomy in Pediatric Solid Tumors

Metastatic disease and the complications of treating metastatic disease are the primary causes of mortality in children with solid malignancies. Nearly 25% of children with solid tumors have metastatic disease at initial diagnosis and another 20% develop metastases during or after treatment. The most common location of these metastases is the lung. The role of surgery in metastatic disease depends greatly on the histology of the primary. In general, tumors that are refractory to adjuvant therapies are most appropriate for pulmonary metastasectomy. This article will summarize the indications for metastasectomy in pediatric solid tumors and discuss the ongoing debate over the technique of metastasectomy in osteosarcoma.