Retroperitoneal leiomyomatosis: a case report

A RARE CASE OF A RETROPERITONEAL LEIOMYOMATOSIS

Leiomyomas are mostly located in the uterus.Retroperitoneal presentation of leiomyomas are rare and have a greater diagnostic challenge.Because retroperinoteal tumours are quite rare and mostly malignant. Therefore, differantial diagnosis is difficult.We report a rare case of retroperitoneal leiomyomatosis, in which there were concurrent leiomyomas in uterus, pelvic and paraaortic regions that are adjacent to pelvic and paraaortic vascular structures.The patient underwent type 1 hysterectomy and bilateral salpingo-oophorectomy and had a total excision of the myomas from adjacent structures. Histological examination of the surgical specimen revealed that leiomyoma. She has been disease -free for 24 months now.

Management of a giant retroperitoneal leiomyoma: a case report

Background

Leiomyomas are benign tumors observed mainly in adult women. The retroperitoneum is a rare location for leiomyomas; almost 100 cases have been reported. Because retroperitoneal leiomyomas are paucisymptomatic and the tumor size at diagnosis is relatively large, surgical management is challenging. Regular follow-up is required because recurrence and malignant sarcomatous transformation have been described in a few cases.

Case presentation

We report a case of a 52-year-old North African woman with a 22-cm retroperitoneal leiomyoma. A preoperative embolization was performed 2 days before surgery. The clinical, therapeutic, and evolutive aspects of this rare entity are discussed.

Conclusions

Despite its benignity, retroperitoneal leiomyoma is a challenging diagnostic, therapeutic, and evolutive condition. Surgeons must consider mainly the tumor’s vascularization. Regular follow-up is mandatory because malignant transformation cannot be excluded.

[Retroperitoneal leiomyoma: report of 2 cases]

Les tumeurs bénignes du muscle lisse sont fréquentes dans le tractus gastro-intestinal et génito-urinaire, et rares au niveau rétro péritonéal. Leur prévalence parmi les tumeurs rétropéritonéales primitives a été estimée entre de 0,5 à 1,2%. Une situation qui conduit à des erreurs de diagnostic. On rapporte dans cet article deux cas de léiomyome rétropéritonéal (LRP) retrouvés chez des femmes âgées entre 47et 54 ans. L'imagerie a mis en évidence une masse rétro-péritonéale, ce qui a motivé une exérèse totale de la tumeur. L'examen anatomopathologique de la pièce opératoire a posé le diagnostic de léiomyome rétro-péritonéal. L’évolution sans récidive était bonne.

Novel KAT6B-KANSL1 fusion gene identified by RNA sequencing in retroperitoneal leiomyoma with t(10;17)(q22;q21)

Retroperitoneal leiomyoma is a rare type of benign smooth muscle tumor almost exclusively found in women and with histopathological features similar to uterine leiomyomas. The pathogenesis of retroperitoneal leiomyoma is unclear and next to nothing is known about the cytogenetics and molecular genetics of the tumor. Here we present the first cytogenetically analyzed retroperitoneal leiomyoma. It had a t(10;17)(q22;q21) as the sole chromosomal abnormality. Using RNA-Sequencing and the ‘grep’ command to search the fastq files of the sequence data we found that the translocation resulted in fusion of the genes KAT6B (10q22) with KANSL1 (17q21). RT-PCR together with direct (Sanger) sequencing verified the presence of a KAT6B-KANSL1 fusion transcript. No reciprocal KANSL1-KAT6B transcript was amplified suggesting that it was either absent or unexpressed. The KAT6B-KANSL1 fusion transcript consists of exons 1 to 3 of KAT6B and exons 11 to 15 of KANSL1, is 3667 bp long, has a 1398 bp long open reading frame, and codes for a 466 amino acid residue protein. The corresponding KAT6B-KANSL1 protein contains the NEMM domain (including the linker histone H1/H5, domain H15) of KAT6B and the PEHE domain of KANSL1. The function of the fusion protein might be regulation of transcription with an affinity for chromatin (linker histone H1/H5) and interaction with the HAT domain of KAT8 (PEHE domain). The tumor expressed HMGA2 and HMGA1 even though 12q14-15 and 6p looked normal by G-banding analysis. The tumor also expressed MED12 in the absence of exon 2 mutations. Overall, the data show that the examined retroperitoneal leiomyoma resembles a subset of uterine leiomyomas in terms of histology and genetics.

Retroperitoneal leiomyomata as a cause of bilateral hydronephrosis and lumbosciatic pain

Leiomyomas can occasionally be found in the pelvic and/or abdominal parietal retroperitoneum. This rare entity is known as retroperitoneal leiomyomata. We report the case of a 46-year-old female with bilateral hydronephrosis and chronic sciatic pain caused by invasive retroperitoneal leiomyoma 3 years after hysterectomy, and a successful outcome after treatment with surgery followed by aromatase inhibitors to control pelvic residual disease. Aromatase inhibitors could be a satisfactory treatment option after surgery to control retroperitoneal leiomyoma residual disease.