Lung and Abdominal Biopsies in the Age of Precision Medicine

Genomic Landscape of Advanced Solid Tumors in Middle East and North Africa Using Circulating Tumor DNA in Routine Clinical Practice

INTRODUCTION

Next-generation sequencing (NGS) of tumor DNA can detect actionable drivers and help guide therapy for patients with advanced-stage cancers. While tissue-based genotyping is considered a standard of care, blood-based genotyping is emerging as a valid alternative. Tumor genomic profiles may vary by region, and data from the Middle East and North Africa (MENA) are not widely available. This study elucidates the genomic landscape of advanced solid cancers in patients from the MENA region by retrospectively analyzing results from NGS circulating tumor DNA (ctDNA) testing.

METHODS

In routine clinical practice, 926 plasma samples from 767 patients with advanced cancers from the MENA region were profiled using a comprehensive NGS assay (Guardant360®). We conducted a pan-cancer analysis and sub-analyses focusing on lung, breast, and colorectal cancers.

RESULTS

In the pan-cancer group, TP53 (58.5%), EGFR (20.4%), and KRAS (18.9%) were the most frequently mutated genes. EGFR (10.2%), FGFR1 (4.9%), and PIK3CA (4.9%) showed the most amplifications, while fusions were observed in 2.7% of patients, including ALK, FGFR2, and RET. For lung adenocarcinoma, EGFR (30.5%), KRAS (19.3%), and ERBB2 (4.6%) were the most frequently identified alterations among the genes recommended for evaluation by the National Comprehensive Cancer Network (NCCN). In patients with breast cancer, PIK3CA (35.3%), ESR1 (21.7%), and BRCA1/2 (13.3%) had the most prevalent alterations among NCCN-recommended genes. In colorectal cancer, KRAS (39.0%), NRAS (8.0%), and BRAF (V600E, 4.0%) were the most observed mutations among genes recommended by the NCCN. Comparing this cohort to publicly available Western and Eastern datasets also indicated similarities (including PIK3CA in breast cancer) and variances (including EGFR in lung adenocarcinoma) in key genes of interest in the analyzed cancer types.

CONCLUSION

Overall, our findings provide insight into the genomic landscape of individuals with advanced solid organ malignancies from the MENA region and support the role of ctDNA in guiding therapeutic decisions.

Clinical indications, safety, and effectiveness of percutaneous image-guided adrenal mass biopsy: an 8-year retrospective analysis in 160 patients

PURPOSE

To assess indications, safety, and effectiveness of percutaneous adrenal mass biopsy in contemporary practice.

METHODS

This institutional review board-approved, retrospective study included all patients undergoing percutaneous image-guided adrenal mass biopsies at an academic health system from January 6, 2015, to January 6, 2023. Patient demographics, biopsy indications, mass size, laboratory data, pathology results, and complications were recorded. Final diagnoses were based on pathology or ≥ 1 year of imaging follow-up when biopsy specimens did not yield malignant tissue. Test performance calculations excluded repeat biopsies. Continuous variables were compared with Student's t test, dichotomous variables with chi-squared test.

RESULTS

A total of 160 patients underwent 186 biopsies. Biopsies were indicated to diagnose metastatic disease (139/186; 74.7%), for oncologic research only (27/186; 14.5%), diagnose metastatic disease and oncologic research (15/186; 8%), and diagnose an incidental adrenal mass (5/186; 2.7%). Biopsy specimens were diagnostic in 154 patients (96.3%) and non-diagnostic in 6 (3.8%). Diagnostic biopsies yielded malignant tissue (n = 136), benign adrenal tissue (n = 12), and benign adrenal neoplasms (n = 6) with sensitivity = 98.6% (136/138), specificity = 100% (16/16), positive predictive value = 100% (136/136), and negative predictive value = 88.9% (16/18). Adverse events followed 11/186 procedures (5.9%) and most minor (7/11, 63.6%). The adverse event rate was similar whether tissue was obtained for clinical or research purposes (10/144; 6.9% vs. 1/42; 2.4%, p = 0.27), despite more specimens obtained for research (5.8 vs. 3.7, p < 0.001).

CONCLUSION

Percutaneous adrenal mass biopsy is safe, accurate, and utilized almost exclusively to diagnose metastatic disease or for oncologic research. The negative predictive value is high when diagnostic tissue samples are obtained. Obtaining specimens for research does not increase adverse event risk.

Feasibility of shape-sensing robotic-assisted bronchoscopy for biomarker identification in patients with thoracic malignancies

OBJECTIVE

Molecular diagnostic assays require samples with high nucleic acid content to generate reliable data. Similarly, programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) requires samples with adequate tumor content. We investigated whether shape-sensing robotic-assisted bronchoscopy (ssRAB) provides adequate samples for molecular and predictive testing.

METHODS

We retrospectively identified diagnostic samples from a prospectively collected database. Pathologic reports were reviewed to assess adequacy of samples for molecular testing and feasibility of PD-L1 IHC. Tumor cellularity was quantified by an independent pathologist using paraffin-embedded sections. Univariable and multivariable linear regression models were constructed to assess associations between lesion- and procedure-related variables and tumor cellularity.

RESULTS

In total, 128 samples were analyzed: 104 primary lung cancers and 24 metastatic lesions. On initial pathologic assessment, ssRAB samples were deemed to be adequate for molecular testing in 84% of cases; on independent review of cellular blocks, median tumor cellularity was 60% (interquartile range, 25%-80%). Hybrid capture-based next-generation sequencing was successful for 25 of 26 samples (96%), polymerase chain reaction-based molecular testing (Idylla; Biocartis) was successful for 49 of 52 samples (94%), and PD-L1 IHC was successful for 61 of 67 samples (91%). Carcinoid and small cell carcinoma histologic subtype and adequacy on rapid on-site evaluation were associated with higher tumor cellularity.

CONCLUSIONS

The ssRAB platform provided adequate tissue for next-generation sequencing, polymerase chain reaction-based molecular testing, and PD-L1 IHC in >80% of cases. Tumor histology and adequacy on intraoperative cytologic assessment might be associated with sample quality and suitability for downstream assays.

An Expert, Multidisciplinary Perspective on Best Practices in Biomarker Testing in Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is a rare and aggressive malignancy that arises from the intrahepatic biliary tree and is associated with a poor prognosis. Until recently, the treatment landscape of advanced/metastatic iCCA has been limited primarily to chemotherapy. In recent years, the advent of biomarker testing has identified actionable genetic alterations in 40%-50% of patients with iCCA, heralding an era of precision medicine for these patients. Biomarker testing using next-generation sequencing (NGS) has since become increasingly relevant in iCCA; however, several challenges and gaps in standard image-guided liver biopsy and processing have been identified. These include variability in tissue acquisition relating to the imaging modality used for biopsy guidance, the biopsy method used, number of passes, needle choice, specimen preparation methods, the desmoplastic nature of the tumor, as well as the lack of communication among the multidisciplinary team. Recognizing these challenges and the lack of evidence-based guidelines for biomarker testing in iCCA, a multidisciplinary team of experts including interventional oncologists, a gastroenterologist, medical oncologists, and pathologists suggest best practices for optimizing tissue collection and biomarker testing in iCCA.

Workflow-Based Design and Evaluation of a Device for CBCT-Guided Biopsy

Biopsies for personalized cancer care can be performed with cone beam computed tomography (CBCT) guidance, but manual needle manipulation remains an issue due to X-ray exposure to physicians. Modern CBCT scanners integrate today real-time imaging and software assistance for needle planning. In this paper, these available features are exploited to design a novel device offering an intermediate level of assistance between simple passive mechanical devices of limited efficiency, and advanced robotic devices requiring adapted procedure workflows. Our resulting system is built to limit its impact on the current manual practice. It is patient-mounted and provides remote control of needle orientation and insertion. A multilayer phantom is specifically developed to reproduce interactions between the needle and soft abdominal tissues. It is used to experimentally evaluate the device added value by comparing assisted versus manual needle insertions. The device is shown to help reducing X-ray exposure by a factor 4, without impacting the accuracy obtained manually.

A Retrospective Multi-Site Academic Center Analysis of Pneumothorax and Associated Risk Factors after CT-Guided Percutaneous Lung Biopsy

PURPOSE

To assess the risk factors, incidence and significance of pneumothorax in patients undergoing CT-guided lung biopsy.

METHODS

Patients who underwent a CT-guided lung biopsy between August 10, 2010 and September 19, 2016 were retrospectively identified. Imaging was assessed for immediate and delayed pneumothorax. Records were reviewed for presence of risk factors and the frequency of complications requiring chest tube placement. 604 patients were identified. Patients who underwent chest wall biopsy (39) or had incomplete data (9) were excluded.

RESULTS

Of 556 patients (average age 66 years, 50.2% women) 26.3% (146/556) had an immediate pneumothorax and 2.7% (15/556) required chest tube placement. 297/410 patients without pneumothorax had a delayed chest X-ray. Pneumothorax developed in 1% (3/297); one patient required chest tube placement. Pneumothorax risk was associated with smaller lesion sizes (OR 0.998; 95% CI (0.997, 0.999); [p = 0.002]) and longer intrapulmonary needle traversal (OR 1.055; 95% CI (1.033, 1.077); [p < 0.001]). Previous ipsilateral lung surgery (OR 0.12; 95% CI (0.031, 0.468); [p = 0.002]) and longer needle traversal through subcutaneous tissue (OR 0.976; 95% CI (0.96, 0.992); [p = 0.0034]) were protective of pneumothorax. History of lung cancer, biopsy technique, and smoking history were not significantly associated with pneumothorax risk.

CONCLUSION

Delayed pneumothorax after CT-guided lung biopsy is rare, developing in 1% of our cohort. Pneumothorax is associated with smaller lesion size and longer intrapulmonary needle traversal. Previous ipsilateral lung surgery and longer needle traversal through subcutaneous tissues are protective of pneumothorax. Stratifying patients based on pneumothorax risk may safely obviate standard post-biopsy delayed chest radiographs.

Laser-heated needle for biopsy tract ablation: In vivo study of rabbit liver biopsy

PURPOSE

To investigate the efficacy of a newly-developed laser-heated core biopsy needle in the thermal ablation of biopsy tract to reduce hemorrhage after biopsy using in vivo rabbit's liver model.

MATERIALS AND METHODS

Five male New Zealand White rabbits weighed between 1.5 and 4.0 kg were anesthetized and their livers were exposed. 18 liver biopsies were performed under control group (without tract ablation, n = 9) and study group (with tract ablation, n = 9) settings. The needle insertion depth (~3 cm) and rate of retraction (~3 mm/s) were fixed in all the experiments. For tract ablation, three different needle temperatures (100, 120 and 150 °C) were compared. The blood loss at each biopsy site was measured by weighing the gauze pads before and after blood absorption. The rabbits were euthanized immediately and the liver specimens were stained with hematoxylin-eosin (H&E) for further histopathological examination (HPE).

RESULTS

The average blood loss in the study group was reduced significantly (p < 0.05) compared to the control group. The highest percentage of bleeding reduction was observed at the needle temperature of 150 °C (93.8%), followed by 120 °C (85.8%) and 100 °C (84.2%). The HPE results show that the laser-heated core biopsy needle was able to cause lateral coagulative necrosis up to 14 mm diameter along the ablation tract.

CONCLUSION

The laser-heated core biopsy needle reduced hemorrhage up to 93.8% and induced homogenous coagulative necrosis along the ablation tract in the rabbits' livers. This could potentially reduce the risk of tumor seeding in clinical settings.

Image-guided biopsy in the age of personalised medicine: strategies for success and safety

Oncology has progressed into an era of personalised medicine, whereby the therapeutic regimen is tailored to the molecular profile of the patient's cancer. Determining personalised therapeutic options is achieved by using tumour genomics and proteomics to identify the specific molecular targets against which candidate drugs can interact. Several dozen targeted drugs, many for multiple cancer types are already widely in clinical use. Molecular profiling of tumours is contingent on high-quality biopsy specimens and the most common method of tissue sampling is image-guided biopsy. Thus, for radiologists performing these biopsies, the paradigm has now shifted away from obtaining specimens simply for histopathological diagnosis to acquiring larger amounts of viable tumour cells for DNA, RNA, or protein analysis. These developments have highlighted the central role now played by radiologists in the delivery of personalised cancer care. This review describes the principles of molecular profiling assays and biopsy techniques for optimising yield, and describes a scoring system to assist in patient selection for percutaneous biopsy.