Similar efficacy toward detecting vulvar cancer (VC) has been reported from indocyanine green (ICG) vs technetium-99m (Tc-99m) combined with blue dye (BD), according to a recent study published in the American Journal of Obstetrics & Gynecology.1
VC is the fourth most common malignancy of the female reproductive tract, making up approximately 5% of gynecological cancers worldwide. Prognosis is improved by early diagnosis, which also increases the 5-year survival rate. Complete lymphadenectomy was the standard screening method before sentinel lymph node (SLN), but it significantly impaired quality of life.
Key takeaways:
- A systematic review compared sentinel lymph node detection methods for vulvar cancer, including technetium-99m, blue dye, indocyanine green (ICG), and superparamagnetic iron oxide (SPIO).
- The combined per-patient detection rate across all methods was 92%, with ICG demonstrating 86% efficacy as a standalone tracer.
- SPIO achieved a 100% per-patient detection rate but had limited data for per-grain detection due to small sample size.
- Investigators concluded that ICG shows potential as an effective, less invasive alternative for vulvar cancer detection.
- Experts emphasized the continued importance of vulvar health awareness and early diagnosis, especially among postmenopausal women.
“In light of… emerging techniques, we recognized the need for a systematic review to compare [detection rates (DRs)] of various SLN methods to support the development of updated clinical guidelines,” wrote investigators.
Comparing VC detection technique
The systematic review and meta-analysis were conducted to compare the DRs for VS of various SLN detection methods, including Tc-99m, BD, ICG, and superparamagnetic iron oxide (SPIO). Observational and randomized controlled trials with female patients undergoing sentinel lymph node biopsy (SLNB) for diagnosed VC were included in the analysis.
Articles were identified through literature searches of the MEDLINE, Embase, CENTRAL, Cochrane, Web of Science, and Scopus databases. Two independent authors screened titles and abstracts, followed by full text. Relevant data included year of publication, first author, study design, treatment details, and outcomes.
There were 61 articles included in the final analysis, 59 of which were observational studies and 2 were randomized controlled trials. Additionally, 27 observational studies were included from citation search, leading to a final study population of 4637 patients.
Detection rates across techniques
Overall, the methods evaluated had a combined per-patient DR of 92% and a combined per-grain DR of 84%. Additional per-patient DRs included:
- 82% for BD
- 98% for Tc-99m
- 86% for ICG
- 100% for SPIO
- 94% for Tc-99m with BD
- 98% for Tc-99m with ICG.
Per-grain DRs for these methods were 69%, 93%, 90%, unknown, 88%, and 95%, respectively. The per-grain DR of SPIO could not be measured because of a small sample size. High-certainty ratings of evidence were reported for all DRs. This data indicated the potential efficacy of ICG as a standalone tracer for VC detection.
“Future studies should focus on large-scale, randomized trials comparing these modalities directly, with a focus on cost-effectiveness, patient-reported outcomes, and workflow integration,” wrote investigators.
Managing vulvar health
Vulvar health remains an ongoing topic of discussion among clinicians, with management in postmenopausal women highlighted by Melissa Mauskar, MD, associate professor at UT Southwestern, in an interview with Contemporary OB/GYN.2
Mauskar highlighted the difficulty of diagnosing and treating vulvar conditions because individual patients often have multiple concurrent conditions. In postmenopausal women, these conditions may also have sources besides menopause, highlighting the need for providers to perform a physical exam.
Potential sources of vulvar discomfort include genitourinary syndrome of menopause, chronic yeast infections, and irritant dermatitis. To help support patients, Mauskar advised providers to normalize conversations about sexual and vulvar health.
“A lot of patients have been to several doctors and have waited a long time before they actually feel comfortable bringing this up,” said Mauskar. “I’ll tell them that often it helps when you have a support team.”
