Transcatheter arterial embolization for unruptured renal angiomyolipoma using a 1.8-Fr tip microballoon catheter with a mixture of ethanol and Lipiodol

Serum lactate dehydrogenase concentration after transcatheter renal artery embolization correlates with reduction in renal angiomyolipoma volume

BACKGROUND

The extent of renal angiomyolipoma (AML) volume reduction after renal transcatheter arterial embolization (TAE) varies between patients, with no predictive measure available.

PURPOSE

To determine whether the serum lactate dehydrogenase (LDH) concentration shortly after TAE correlates with the extent of tumor shrinkage.

MATERIAL AND METHODS

In a cohort of 36 patients undergoing prophylactic renal TAE for unruptured renal AML, we retrospectively acquired data from patient medical records, including serum LDH before and within 7 days after TAE and the tumor volume before and 12-36 months after TAE. The relationship between the serum level of LDH and reduction in tumor volume was evaluated using Spearman correlation analysis.

RESULTS

The median LDH concentration was significantly higher after TAE than before (909.0 U/L vs. 186.5 U/L). This early post-TAE serum LDH level and LDH index (post-TAE LDH / pre-TAE LDH) correlated significantly and positively with the absolute decrease in tumor volume (both P < 0.0001). We observed no significant correlation between the relative tumor volume reduction and serum LDH level or LDH index.

CONCLUSION

Serum LDH elevation occurs shortly after TAE and correlates with the extent of absolute decrease in AML volume at 12-36 months after TAE. Further large-scale studies are warranted to confirm the predictive role of post-TAE serum LDH level and LDH index in tumor shrinkage in patients with unruptured renal AML.

Prophylactic renal artery embolization before pregnancy in patients with lymphangioleiomyomatosis and renal angiomyolipoma

OBJECTIVE

Pregnant patients with lymphangioleiomyomatosis (LAM) and renal angiomyolipomas (AMLs) require care for both renal AMLs and pulmonary dysfunction because AMLs can grow and rupture during pregnancy, potentially causing hemorrhagic shock and fetal death. This study examined whether prophylactic transcatheter arterial embolization (TAE) could prevent the pregnancy-associated growth and rupture of renal AMLs in patients with LAM.

METHODS

This retrospective study included five women with 14 renal AMLs (initial diameter, ≥2 cm) first encountered between September 2010 and August 2015 who subsequently became pregnant. Seven tumors in five patients were embolized, and seven tumors in two patients were not treated. Changes in the volume of each tumor were evaluated.

RESULTS

Untreated tumors were much more likely to grow than embolized tumors both during pregnancy (100% vs. 0%) and at the first follow-up visit after delivery (100% vs. 14%). One untreated hypervascular tumor grew rapidly during pregnancy to 409% of the pretreatment volume. No tumor ruptured.

CONCLUSIONS

Prophylactic pre-pregnancy TAE decreased the growth and bleeding of renal AMLs during pregnancy in patients with LAM. TAE can be recommended for hypervascular tumors before pregnancy regardless of the size of the aneurysm.

Spontaneous Rupture of Large Angiomyolipoma of the Kidney: A Rare Case

Angiomyolipoma is the most frequent neoplasm of the kidney. It may have a wide range of clinical manifestations, but it is usually detected incidentally on cross-sectional images. Rupture and hemorrhage of angiomyolipoma is an important concern for large lesions. We present the case of a 42-year-old female, with no history of urinary stones, who presented with a sudden-onset left flank pain for eight hours. Upon examination, she was tachycardic and hypotensive. Abdominal examination revealed a left-sided flank mass. Abdominal computed tomography (CT) scan with intravenous contrast demonstrated a heterogeneous mass lesion in the left kidney with mixed attenuation and had a macroscopic fat density that was surrounded by a large hematoma. Subsequently, transcatheter renal artery embolization was performed with no complications. The procedure was able to control the active bleeding. Then, a total nephrectomy was performed, and the hematoma was evacuated during laparotomy. Spontaneous nontraumatic renal hemorrhage is a very rare condition. Clinicians should keep a high index of suspicion for this condition when they encounter a patient with the clinical triad of flank pain, flank mass, and hypotension. The case demonstrated the role of endovascular embolization of angiomyolipoma to control life-threatening hemorrhage.

Selective Arterial Embolization of Renal Angiomyolipomas with a N-Butyl Cyanoacrylate-Lipiodol Mixture: Efficacy, Safety, Short- and Mid-Term Outcomes

Selective arterial embolization (SAE) for renal angiomyolipoma (rAML) is effective to treat or prevent bleeding. We report our experience using a cyanoacrylate–Lipiodol mixture. We performed a single-center retrospective review of all rAMLs embolized with cyanoacrylate glue between July 2014 and June 2020. Demographics, tuberous sclerosis complex (TSC) status, clinical presentation, angiography features, and follow-up data were recorded. Pre- and post-procedure rAML sizes and volumes were estimated from computed tomography (CT) or magnetic resonance imaging (MRI) studies. Kidney function was assessed before and after the procedure. We identified 24 patients (22 females and 2 males, mean age 51 years) treated for 27 AMLs, either prophylactically (n = 20) or as an emergency (n = 4). Technical success was achieved for 25/27 AMLs; two patients, each with a single AML, required nephrectomy and repeated embolization, respectively. Major complications occurred in three patients and minor complications such as postembolization syndrome in 15 patients. AML volume reduction after embolization was 55.1% after a mean follow-up of 15 months (range, 1–72 months). Factors associated with greater volume reduction were a smaller percentage of fat (p = 0.001), larger initial rAML volume (p = 0.014), and longer follow-up (p = 0.0001). The mean creatinine level did not change after SAE. Embolization of rAMLs with a mixture of cyanoacrylate and Lipiodol is feasible, safe, and effective in significantly decreasing tumor volume.