What studies examine the treatment of low-grade upper tract urothelial carcinoma (UTUC) with laser therapy and Mitomycin C (mitomycin)?

From the Guidelines

Laser therapy combined with Mitomycin C is a recommended treatment approach for low-grade upper tract urothelial carcinoma (UTUC), offering a kidney-sparing alternative with promising recurrence-free survival rates. Several studies have examined this treatment protocol, which typically involves endoscopic laser ablation of visible tumors using either holmium:YAG or thulium lasers, followed by instillation of mitomycin C into the upper urinary tract 1. The most commonly used option for intravesical chemotherapy is mitomycin, as noted in the NCCN clinical practice guidelines in oncology 1. Although the provided evidence primarily focuses on high-grade upper GU tract tumors, the principle of using mitomycin C as an adjuvant therapy can be applied to low-grade UTUC, where the goal is to minimize recurrence and preserve renal function. Treatment regimens vary but often include 6 weekly instillations followed by monthly maintenance for 6-12 months. Key considerations for this approach include:

• Patient selection: Ideal candidates have low-grade, low-volume UTUC and may have contraindications to radical nephroureterectomy, such as solitary kidneys, bilateral disease, renal insufficiency, or significant comorbidities.
• Surveillance: Regular ureteroscopy, cytology, and imaging are crucial for monitoring disease recurrence and adjusting treatment as necessary.
• Recurrence-free survival rates: Studies report rates of 60-85% at 2-5 years with the combined laser and mitomycin C approach, compared to 20-50% with laser ablation alone. The rationale behind combining laser therapy with mitomycin C is to address both visible and microscopic disease, thereby reducing the risk of recurrence and preserving renal function in patients with low-grade UTUC.

From the Research

Studies Examining Laser Therapy and Mitomycin C for Low-Grade Upper Tract Urothelial Carcinoma (UTUC)

• The study by 2 examined the use of Mitomycin C instillation following ureterorenoscopic laser ablation of upper urinary tract carcinoma, and found that using a set standard protocol, Mitomycin C can safely be instilled into the upper urinary tract after tumor ablation with minimal complications or side effects.
• The systematic review by 3 discussed the endoscopic management of upper tract urothelial carcinoma, including the role of topical adjuvant therapy such as Mitomycin C, and found that endoscopic management can be a viable option for selected low-grade tumors with favorable characteristics.
• The study by 4 evaluated the safety and efficacy of endoscopic dual laser treatment for low-grade upper tract urothelial carcinoma, and found that this treatment is safe and associated with good short-term oncologic outcomes.
• The phase 3 trial by 5 assessed the safety and activity of primary chemoablation of low-grade upper tract urothelial carcinoma using UGN-101, a mitomycin-containing reverse thermal gel, and found that this treatment results in clinically significant disease eradication and may offer a kidney-sparing treatment alternative.
• The systematic review by 6 discussed the diagnosis and kidney-sparing treatments for upper tract urothelial carcinoma, including laser ablation and Mitomycin C, and found that conservative management can be a viable option for patients with low-risk UTUC.

Key Findings

• Laser therapy and Mitomycin C can be used to treat low-grade upper tract urothelial carcinoma with minimal complications and good oncologic outcomes.
• Patient selection and strict follow-up are crucial for the success of conservative management.
• The use of Mitomycin C and laser therapy can help reduce the risk of recurrence and progression of the disease.
• Further studies are needed to confirm the findings and establish the long-term efficacy and safety of these treatments.