Robotic treatment of giant adrenal myelolipoma: A case report and review of the literature

Abstract

Adrenal myelolipoma is a rare mesenchymal tumour with benign biological behaviour that is mainly composed of mature adipose and myeloid tissue. Both sexes are equally affected, most commonly between the fifth and seventh decades of life. The diagnosis of adrenal myelolipoma is mostly incidental. Although it may occasionally be associated with necrosis, rupture and haemorrhage, causing abdominal pain, this tumour is usually asymptomatic. Consequently, management is conservative, while surgical treatment is reserved for symptomatic cases, or for masses growing quickly or to a size >6 cm. Giant myelolipomas (sized >10 cm) are rare. Open radical adrenalectomy is the standard treatment for giant myelolipomas, while the minimally invasive approach has been used in only few cases. We herein report the case of a patient with a giant adrenal myelolipoma who underwent robotic partial adrenalectomy. To the best of our knowledge, this is the largest giant adrenal myelolipoma treated with robotic surgery reported in the literature to date. A 55-year-old male patient underwent an abdominal computed tomography scan during follow-up after radical prostatectomy for prostate cancer Gleason Score 6 (ISUP 1) due to biochemical recurrence. The examination revealed a right hypodense adrenal mass, sized 16×13 cm. Abdominal magnetic resonance imaging confirmed the presence of characteristics suggestive of a myelolipoma. The patient did not report any symptoms. Due to the benign characteristics of the mass, robotic partial adrenalectomy and enucleation of the mass were performed. The operative time and estimated blood loss were 205 min and 100 ml, respectively. No intra- or postoperative complications occurred. The patient was mobilized on the first postoperative day and the time to flatus was 36 h; the length of hospitalization was 4 days. Histological examination confirmed the diagnosis of adrenal myelolipoma, sized 18×11.5×6 cm. No tumour recurrence occurred over a follow-up period of 12 months. In conclusion, robotic surgery allows performing partial adrenalectomy with a lower risk of bleeding and with preservation of healthy adrenal tissue, which is of paramount importance for the patient as it reduces recovery time and the need for medical substitution therapy.

Keywords: adrenal masses; adrenal myelolipoma; benign adrenal tumour; giant myelolipoma; mesenchymal tumour; partial adrenalectomy; robotic adrenalectomy; robotic surgery; robotic transperitoneal adrenalectomy.

Figure 1.

(A) Computed tomography and (B) magnetic resonance imaging scan showing the giant right adrenal myelolipoma.

Figure 2.

Trocar placement. The optical trocar (O) was positioned between the transumbilical and periumbilical lines. Two robotic trocars (R) were placed on the pararectal line at 8 cm from O. The AirSeal^® trocar (AS) was placed between O and the more caudal R. The liver retractor trocar (L) was placed subxifoidally on the paraumbilical line.

Figure 3.

Macroscopic view of the resected giant myelolipoma.