Tubulo-squamous polyp of the vagina

Epidemiology

Most cases occur in postmenopausal women.

Clinical features

Presentation may be with postmenopausal bleeding. The polyps occur anywhere within the vagina, most often in the upper vagina.

Macroscopic appearances

The polyps are up to 3 cm in size.

Histopathology

There is an admixture of squamous epithelium and tubules within a hypocellular fibrous stroma. The squamous component is glycogenated and eosinophilic or clear. The centres of the squamous nests contain keratinous debris and the margins show peripheral palisading. Embedded within he squamous epithelium, there are small tubules lined by cuboidal cells. Where tubules occur outwith the squamous islands, there is a double layer of glandular epithelium and there may be micropapillary projections into the lumen. The surface is covered by squamous epithelium which may be focally keratinised.

Immunohistochemistry

	Squamous epithelium	Tubular epithelium	Stroma
AE1/AE3	4/41	4/41	negative1
CK7	4/41	4/41	negative1
LP34	4/41	focally positive or negative1	negative1
34bE12	4/41	focally positive or negative1	negative1
CK20	0/41	0/41	negative1
Thrombomodulin	1/4focally positive1	0/41	negative1
CD10	focally positivity1	luminal positivity1	negative1
Oestrogen receptor	strongly positive1	focal weak positivity or negative1	strongly positive1
Progesterone receptor	negative1	negative1	positive1
Prostatic acid phosphatase		3/4variably positive1
Prostate specific antigen		2/4variably positive1
MIB1 index	low: only occasional nuclei positive1

Differential diagnosis

Fibro-epithelial polyp: lack an epithelial component within the stroma, no tubular component. The stroma commonly includes atypical cells.
Smooth muscle tumours
Angiomyofibroblastoma
Superficial myofibroblastoma of the lower female genital tract
Vaginal adenosis with squamous metaplasia does not usually form a polyp
Mixed tumour of the vagina (spindle cell epithelioma): occurs in premenopausal women in proximity to the hymenal ring in the lower vagina. The spindle cell component predominates, is cellular and is diffusely positive for cytokeratins.
Synovial sarcoma: the epithelial component is mainly glandular and both epithelium and stroma are malignant.
Adenoid basal carcinoma, occurs in the cervix, not the vagina. There is typically dysplasia of the surface epithelium.
Squamous cell carcinoma.
Brenner tumour of the vagina: this is the designation under which some tubulo-squamous polyps have been described.

References

1 McCluggage WG,Young RH. Tubulo-squamous polyp: a report of ten cases of a distinctive hitherto uncharacterized vaginal polyp. Am J Surg Pathol 2007; 31:1013-9

This page last revised 11.11.2007.