Metastasi orale da leiomiosarcoma: un caso clinico

OBJECTIVES Leiomyosarcoma is a malignant neoplasm of smooth muscle differentiation, that represents 5-10% of all soft tissue sarcomas, and represents almost the 24% among all mesenchymal malignancies. This lesion is exceedingly rare in the oral cavity and represents less than 1% of oral sarcomas. Only few primary oral leiomyosarcomas have been described in literature, and its incidence peak showed to be in the fifth-seventh decades, appearing as a slowly growing infiltrative nodule. The aim of this clinical case is to describe a rare case of secondary leiomyosarcoma in the oral cavity, diagnosed at the Oral Medicine and Pathology Unit (S.C. Clinica di Chirurgia Maxillo-Facciale e Odontostomatologia, Ospedale Maggiore, Trieste, Italy). MATERIALS AND METHODS A 61-year-old male patient, was referred in October 2023 due to the onset of an exophytic mass in the vestibulum of the right posterior maxilla, which had an increased overgrowth in the previous twenty days. He was diagnosed with a left leg infiltrating leiomyosarcoma in 2014 and underwent polychemotherapy. Subcutaneous, pulmonary and lymph nodal metastasis had been already detected through CT-PET. The oral lesion had a parenchymatous consistency and a multilobulate aspect, together with vegetative and hyperkeratotic component. Its maximum diameter was around 5 cm. The swelling was visible also extra-orally, accompanied with a left latero-cervical mass. The intra-oral examination presented also a small ovoidal mass in the lower labial mucosa. An orthopanoramic radiograph was performed, to detect any bone involvement, and no alterations were highlighted. Therefore, in agreement with the patient, an incisional biopsy was immediately performed. RESULTS The incisional biopsy was performed under local anesthesia, and the surgical specimen was sent for histological analysis. No sutures were applied, and hemostasis was obtained through compression with wet gauzes. The histological analysis revealed the presence of oral mucosa infiltrated with malign neoplasm with an epithelioid pattern and focal spindle cell aspects. The immunophenotype analysis showed a spotty positivity to muscular markers as smooth muscle actin and desmin, and an aspecific response to h-caldesmon. Other tested markers, CK 5/6, p40, HHF-35 and myogenin proved to be negative. The morpho-histopathologic diagnosis showed therefore to be coherent with a leiomyosarcoma metastasis. In this specific case, the mild response to the muscular markers could be ascribable to the previous chemotherapeutic treatment. Due to systemic complications, the patient was hospitalized in a long-term care clinic and died few weeks later. CONCLUSIONS This report highlighted the clinical and diagnostic management on the oral involvement of a systemic condition. Unfortunately, it was not possible to recall the patient on programmed follow-up, to evaluate possible local progressions of the lesion, due to a worsening of his systemic conditions. CLINICAL SIGNIFICANCE The following manuscript points the intra-oral aspect of a systemic malign lesion, showing the correct clinical management of the case, obtained with a thorough diagnostic framework through histological and immunophenotype analyses.