Hamartomatous Angiolipoma of the Parotid Gland (Sialoangiolipoma)

Abstract

Mesenchymal tumors of the salivary glands are rare and mostly localized to the parotid gland. We report on the clinico-pathological features of a distinct parotid tumor occurred in a newborn, showing glandular structures admixed with mature lipocytes and blood vessels in variable proportions. This was a well-circumscribed and slowly growing nodule of the superficial parotid lobe, mostly reddish in color with white-yellowish striations. Microscopically, a distinct lobular architecture was evident, along with normal-appearing acinar and ductal structures with interposed loose fibrous stroma. The latter contained aggregates of mature lipocytes and variably sized blood vessels. The morphological features of the lesion reported herein recapitulate those of sialolipoma but also include the presence of a prominent vascular component intimately admixed with both the glandular and the adipose tissues. At variance with salivary lipoadenoma, the glandular component in the current case distinctly showed all the cellular components of normal salivary (serous) glands. In consideration of the young age of the patient, the minimal growth rate and the histological features of the lesion, we hypothesize a hamartomatous origin for this lesion and propose the designation of sialoangiolipoma.

Fat-Containing Salivary Gland Tumors: A Review

“…Spindle cell lipoma [37], osteolipoma [38], fibrolipoma [39], angiolipoma [40], lipoblastoma [41], hibernoma [42], and pleomorphic lipoma [43] are the main subtypes reported. Of these, spindle cell lipoma may mimic myoepithelioma with extensive lipometaplasia.…”

Submandibular sialoangiolipoma: A rare hamartomatous lesion causing diagnostic dialemma

“…[1] These comprise the angiomas, schwannomas, neurofibromas, lipomas and rarely hibernomas, lipoblastoma and pleomorphic/spindle cell lipomas. [1] Combined mesenchymal tumors like sialolipoma, lipoadenomas, angiolipomas have been described only exceptionally in salivary glands with most of the cases being reported in parotid gland. [1–4] Only four cases of sialolipomas have been described till now in the submandibular gland with three occurring in adults and one in a child.…”

“…[1] Combined mesenchymal tumors like sialolipoma, lipoadenomas, angiolipomas have been described only exceptionally in salivary glands with most of the cases being reported in parotid gland. [1–4] Only four cases of sialolipomas have been described till now in the submandibular gland with three occurring in adults and one in a child. [4] However, to the best of our knowledge, no case of submandibular gland hamartoma comprising such myriad structures including salivary gland ducts, skeletal muscle fibers and nerve within a vessel wall has been described in literature.…”

Vascular hamartoma of the parotid gland

“…Maiorano et al 11 reported on the clinicopathological features of a distinct parotid tumour in a newborn, showing normal glandular structures admixed with mature lipocytes and blood vessels in variable proportions, and identified the pathology as a sialoangiolipoma. However, as it was composed of normal-looking acinar and ductal structures, interposed with mature lipocytes and blood vessels, it has indigenous tissues admixed with mature tissues and thus it fits into the Willis definition of a hamartoma 2.…”