Percutaneous Image-Guided Core Needle Biopsy of Neuroendocrine Tumors: How Common Is Intraprocedural Carcinoid Crisis?

Clinical question
What is the incidence of carcinoid crisis, physiologic disturbances, and other complications during percutaneous image-guided core needle biopsy of neuroendocrine tumors (NETs) in the lung and the liver?

Take away point
Percutaneous image-guided core biopsy of NETs is quite safe, with very low complication rate and no definite carcinoid crisis within the current small cohort.

Reference
Percutaneous Image-Guided Core Needle Biopsy of Neuroendocrine Tumors: How Common Is Intraprocedural Carcinoid Crisis? Jang, Samuel et al. Journal of Vascular and Interventional Radiology, Volume 32, Issue 5, 2021, Pages 745-751.

Click here for abstract

Study design
Single-center retrospective (10 years) cohort study, including 106 biopsies from 16 patients with pathology proven diagnosis of carcinoid or NET.

Funding Source
Self-funded or unfunded.

Setting
Mayo Clinic Department of Radiology, Rochester, Minnesota

Figure

Figures: (Left) Percutaneous CT-guided biopsy of a 2.3-cm lesion in the right upper lobe. Histopathologic diagnosis was ‟typical carcinoid tumor.” (Right) Percutaneous US-guided biopsy of a 3.0-cm lesion with a hypoechoic rim in the peripheral posterior right hepatic lobe. Histopathologic diagnosis was ‟well-differentiated neuroendocrine tumor.”

Summary

Neuroendocrine tumors (NETs) can produce vasoactive hormones that cause a range of physiologic events which are collectively known as carcinoid syndrome. It predominantly occurs in serotonin-producing tumors of the small intestine and patients with hepatic metastasis. A potential life-threatening complication of carcinoid syndrome is carcinoid crisis, caused by the sudden massive release of vasoactive substances that precipitate physiologic crisis, triggered by interventions and manipulation of these tumors. Incidence of carcinoid crisis has been studied in multiple therapeutic procedures, however, no retrospective cohort studies that examine the rate of adverse physiologic effects from image-guided percutaneous biopsy of NETs have been completed.

Retrospectively 106 computed tomography (CT) or ultrasound (US)-guided core needle biopsies of lung and liver NETs from 95 patients were reviewed over a 10 year period (Jan 2010 to Jan 2020). Patients’ mean age was 64 ± 13 years, and 48% were female. Small bowel primary site was the most common (33%). Most patients had widely metastatic disease, while only 32 patients (34%) had fewer than 5 lesions at the time of biopsy. Thirty two (34%) patients had pre-existing symptoms of carcinoid syndrome, the most common symptom being diarrhea (88%). The mean tumor size was 3.2 ± 2.6 cm, and mean number of passes was 3.4 ± 1.6. A 17/18-gauge needle was used in 91% of the biopsies. Thirteen (12%) patients received either outpatient or prophylactic octreotide. Patients’ malignancies were deemed functional or nonfunctional based on clinical documentation determined by the patients’ oncologist 30 day prior to biopsy, of which 36% of the tumors were deemed functional. Neuroendocrine markers including were available for Potential physiological disturbances related to the biopsies were analyzed based on nursing documentation noting the exact times of the biopsies, and individual patients’ oxygen saturation, heart rate, blood pressure, and respiratory rate immediately prior to the first tumor passage and just after the last passage.

Carcinoid crisis as it was defined in the study was not encountered in the studied cohort. One major complication and four minor complications were encountered. Paired t test was used to compare pre and post biopsy physiological data, of which no statistically significant change was observed, even in multiple subgroup analysis of patients with proposed risk factors. Mean and standard deviation were used for continuous variables, and frequency counts with percentages were used for categorical variables. No previous studies of NET biopsy described carcinoid crisis as a complication. Taken in context with the current study, the authors conclude carcinoid crisis from core biopsy is extremely rare (only 4 case reports), and percutaneous image-guided biopsy of NETs can likely be performed without prophylactic octreotide administration.

Commentary

The authors acknowledge study limitations, including limitations of their statistical analysis due to the low number of complications, no standard panel of pre-procedure neuroendocrine markers for each patient, and the subjective nature of documenting pre-existing carcinoid crisis based on EMR documentation. However, I believe this study was well-performed and legitimate for a single center retrospective cohort, especially considering the rarity of NET and a10-year time frame. The study is unique in that it is the only study to analyze intraprocedural physiologic data in the context of biopsy of NETs, showing no statistically significant change from pre- to post-biopsy, even in subgroup analysis.

I agree with the authors' clinically significant conclusions, and think they have future implications in guiding proceduralists' approach to biopsy of NETs. The authors make a strong case that carcinoid crisis in percutaneous biopsy of NET is extremely rare, in presenting both the current study and other similar biopsy studies of NET. They also conclude prophylactic octreotide administration prior to percutaneous biopsy is likely not necessary regardless of tumor burden, tumor functional status, and neuroendocrine markers. The authors contextualize this conclusion in saying that the proceduralist should remain vigilant of carcinoid crisis and prepared to respond swiftly.

Post Author
Gregory Rufener, MD
Radiology Resident (PGY-4)
Department of Diagnostic Radiology
Oregon Health and Science University, Portland, Oregon
Twitter: @gregoryrufener

Edited and formatted by @NingchengLi