Sarcoma-like mural nodules in mucinous cystic tumour of the ovary

Histopathology

Mucinous cystic tumours of the ovary (whether benign, borderline or malignant) may contain mural nodules, which can be subdivided into:

• sarcomas. These occur in older women, form larger poorly circumscribed nodules with frequent vascular invasion and are composed of a monotonous population of spindle cells. They show aggressive behaviour.

• sarcoma-like mural nodules, SLMN. These predominantly occur in younger women, are smaller (<6cm), are sharply demarcated and do not aggravate the prognosis. They show a heterogeneous cell population. They may be subdivided into;

  • epulis-like lesions with numerous multinucleate osteoclast-like giant cells.

  • pleomorphic and spindle cell type: the spindle cells show hyperchromatic nuclei and are admixed with a prominent inflammatory component and scattered multinucleate giant cells.

  • histiocytic type, composed mainly of mononuclear cells with copious cytoplasm.

• foci of anaplastic carcinoma. These tend to be large and poorly circumscribed and show obvious carcinomatous differentiation. They lack an inflammatory cell component and lack giant cells.

Immunohistochemistry of SLMN

The negativity for ALK contrasts with inflammatory myofibroblastic tumours.

References

1Bague, S., I. M. Rodriguez, Prat, J.. (2002). "Sarcoma-like mural nodules in mucinous cystic tumors of the ovary revisited: a clinicopathologic analysis of 10 additional cases." Am J Surg Pathol 26(11): 1467-76.

This page last revised 1.12.2002.

©SMUHT/PW Bishop