Indian Journal of Pathology and Microbiology

LETTER TO EDITOR
Year
: 2017  |  Volume : 60  |  Issue : 4  |  Page : 624--626

Leiomyosarcoma of parotid gland


Asawari Ambekar, CS Soman, Simi Bhatia 
 Junior Histopathologist, Central Reference Laboratory Mumbai, Prime Square Building, Gaiwadi Industrial, Goregaon West, Mumbai, Maharashtra, India

Correspondence Address:
Asawari Ambekar
R.B.I. Soc No. 2 B/5 Gavand Path Thane (West) - 400 602, Maharashtra
India




How to cite this article:
Ambekar A, Soman C S, Bhatia S. Leiomyosarcoma of parotid gland.Indian J Pathol Microbiol 2017;60:624-626


How to cite this URL:
Ambekar A, Soman C S, Bhatia S. Leiomyosarcoma of parotid gland. Indian J Pathol Microbiol [serial online] 2017 [cited 2019 Oct 17 ];60:624-626
Available from: http://www.ijpmonline.org/text.asp?2017/60/4/624/222979


Full Text



Editor,

Primary sarcomas of the salivary glands are rare accounting for 0.3%–1.5% of salivary gland neoplasms and 1.5%–2.3% of malignant salivary tumors.[1] Leiomyosarcomas which are tumors of the smooth muscle cells are infrequently found in the head and neck region and are an exceptional find in the salivary glands.

We present the case of a 58-year-old woman, who, presented with a history of progressively increasing painless mass over the left side of face over a period of 1 year. Clinical examination revealed the mass to be over the left parotid and measured 3 cm × 3 cm. Magnetic resonance imaging of the head and neck region showed altered signal intensity in the superficial lobe of the left parotid gland, suggestive of a well-encapsulated neoplasm without any deep lobe or facial nerve involvement. Ultrasonographic examination of the abdomen did not reveal any mass in the abdomen or the female genital tract. Fine-needle aspiration cytology revealed cellular smears with features of malignant spindle cell neoplasm. Based on this, the patient underwent superficial parotidectomy of the left lobe. We were consulted for expert opinion on this case and provided with two paraffin blocks. The H and E slides showed salivary gland with a circumscribed tumor composed of spindle cells arranged in interlacing bundles and fascicles [Figure 1]a. The tumor cells had moderate cytoplasm and cigar-shaped nuclei. Tumor giant cells were noted along with brisk and atypical mitotic bodies [Figure 1]b. The margins were clear.{Figure 1}

On immunohistochemical examination, the tumor cells strongly expressed smooth muscle actin [Figure 2]b and Desmin [Figure 2]c and were immunonegative for pancytokeratin [Figure 2]a and S100p [Figure 2]e. Expression for Bcl2, [Figure 2]d, EMA [Figure 2]f, and CD34 [Figure 2]g was focal. The proliferation index with Ki-67 was 20%–25% [Figure 2]h.{Figure 2}

Leiomyosarcoma, a soft tissue sarcoma, is generally seen in the female genital tract, extremities, and abdominal cavity and accounts for 7% of all soft tissue sarcomas.[2] LMS, though is known to arise from smooth muscle cells, is now increasingly recognized to originate from the myoepithelial cells and undifferentiated pluripotential cells.[3],[4] The rarity of leiomyosarcoma in the head and neck region may be attributed to relative paucity of smooth muscle in this area. In a clinical setting, a lump or mass which has not received a diagnostic label in the past that shows changes over a 3–6 week period must be urgently referred for histopathological examination. The diagnosis in our case was based on correlation of histologic features with the immunoexpression for antibodies for SMA and Desmin and its lack of expression for pancytokeratin and S100p. The tumor cells also showed focal expression for EMA, Bcl2, and CD34. Thus, the histologic differentials of various sarcomas such as malignant peripheral nerve sheath tumor, fibrosarcoma, angiosarcoma, rhabdomyosarcoma, and synovial sarcoma were excluded on the basis of expression of these IHC stains.

We consider our case to be a primary LMS of parotid gland as it fulfills all of the criteria of primary salivary gland sarcoma, namely, (1) the patient must not have, or have had, a sarcoma elsewhere; (2) a metastasis to the gland from malignancies of the skin or mucosa of the upper aerodigestive tract must be excluded; (3) the gross and microscopic appearances should be consistent with a primary origin, rather than invasion from the adjacent soft tissues; and (4) within the limits of the microscopic study of multiple sections, carcinosarcoma has to be excluded.[1]

The treatment modality includes surgery with adjuvant radiotherapy. Our patient underwent superficial parotidectomy and is presently doing well.

References

1EI Ochi MR, Chahdi H, Rharrassi I, Albouzidi A, Oukabli M. Primary leiomyosarcoma of the submandibular gland: A case report. BMC Clin Pathol 2015;15:22.
2Sethi A, Mrig S, Sethi D, Mandal AK, Agarwal AK. Parotid gland leiomyosarcoma in a child: An extremely unusual neoplasm. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;102:82-4.
3Nagpal DK, Prabhu PR, Shah A, Palaskar S. Leimyosarcoma of the buccal mucosa and review of literature. J Oral Maxillofac Pathol 2013;17:149.
4Maheshwari GK, Baboo HA, Patel MH, Wadhwa MK, Gopal U. Leiomyosarcoma of the parotid gland metastatic to the scalp: A rare primary location with unusual metastatic lesion. Turk J Cancer 2003;33:191.