Vagina and vulva are the most frequent site for tumor development in female genital system in bitches¹. The vaginal and vulval tumors contribute 2.4-3 per cent of tumors in dogs². The commonly reported reproductive tract neoplasms are leiomyoma, fibroma and transmissible venereal tumor³. Fibroma and leiomyofibroma are benign tumors of the fibrous connective tissue and smooth muscles, respectively⁴. Two main types of fibroma are hard and soft fibroma. Hard fibromas are hard and firm with cut surface usually dry and white and consist of mature fibrous connective tissue. Soft fibroma appears spongy, vascular and edematous³. Medium-aged, non-spayed, nulliparous dogs are commonly encountered reproductive tract tumours and surgery is the treatment of choice⁵. This report presents the morphological features of a surgically excised benign fibromatous tumour from a bitch.

A 6-year-old, 18 Kg entire body weight, nulliparous, crossbreed canine female was presented to the Teaching Veterinary Clinical Complex cum Referal Veterinary Polyclinic IVRI, Bareilly, India for the investigation of vulvar bleeding and tenesmus. The dog had regular oestrus cycles, but unable to conceive. The animal was alert and in good body condition. Heart rate and pulse rate were 78 beats per minute, 67 pulse per minutes respectively. Vaginal examination showed a spongy mass with a smooth surface on palpation located on right ventral wall of vaginal lumen.

The patient was prepared for surgery by clipping and shaving the hairs around the perivulvar region. Atropine (dose and route used: 0.04 mg/kg subcutaneously, manufacturers detail: Curopine 1mg/ml, Pharma cure laboratories), Xylazine (dose and route used:1.5mg/kg intramuscularily, manufacturers detail: xylozin 23.32 mg/ml, Zenley animal health) and ketamine (dose and route used: 7 mg/kg intramucluraly, manufacturers detail: ketmin 50 mg/ml, Themis Medicare Ltd.) were given for anaesthesia. Anesthesia was maintained with 1:1 ratio of ketamine (ketmin 50 mg/ml, Themis Medicare Ltd.) and diazepam (Calmose 5mg/ml, Sun pharma) at the rate of 1ml/20 Kg intravenously. After induction of anesthesia, patient was positioned in dorsal recumbency and scrubing was done with chlrohexidine solution with final mopping with povidone iodine. The patient was properly draped and sterilized vaginal speculum was used for the visualization and localization of the tumour mass. With the help of artery forcep the mass was grasped (Fig 1) and by using electrocautery the mass was cut from the base. Postoperatively patient was treated with antibiotics (Inj. Cefotaxime 15 mg/Kg twice a day intravenously, manufacturers detail: cefotax 250 mg, modern laboratories) and with analgesic Meloxicam (0.5 mg/Kg twice a day intramuscularily, manufacturers detail: Melonex 5 mg/ml, intas pharmaceutical Ltd.) for seven days and advised to return for check up after 7 days. There was no recurrence of the tumour within 6 months after the surgery.

The tumorous tissue excised from the vagina was fixed in formalin (10%) and processed for histological examination. The tissue section was stained with hematoxylin and eosin stain. Large numbers of fibroblast and very few fibrocytes were seen. Eosinophilic collagen fibres were arranged in wavy and interwoven manner. Tissue had reduced cellularity (Fig 2a and 2b). The mass was diagnosed as soft fibroma.

There are different kinds of growths observed in the vagina of the bitches and these are leiomyomas, neurofibroma, hyperplasia, adenoma etc. Mesenchymal derived benign tumors particularly from smooth muscle fibres are the most common type of growths found in the uterus and vagina of the dogs. Occurrences of uterine neoplasmas are very rare and it contributes around 0.3-0.4% of all tumors in dogs². Leiomyofibroma and fibroma are the benign tumors of smooth muscles and fibrous connective tissue³. Benign tumors are curable and surgery is the treatment of choice in most benign lesions and vulvovaginal tumors are rarely identified as a cause of death⁶. Histopathologically leiomyomas are non-encapsulated and well circumscribed neoplasm having interlacing fascicles and there is abundant cytoplasm³. Around 86% of vulvar and vaginal tumors are reported to be benign smooth muscle tumors. Ovarian hormones are responsible for development of the benign tumour in the female genital tract⁷. These tumors do not cause infertility; rather, they interfere with mating and whelping⁸. Tumor classification is usually done on the basis of site of occurrence⁹. According to Rollon et al. (2008), use of aglepristone (10mg/kg subcutaneously on day 1, 2, 8, 15, 28 and 35, manufacturers detail: Alizin 30 mg/ml, Virbac animal health) in vaginal fibroma is curative in dogs¹⁰, but in this case surgical removal was done as only small single mass was present in the tubular vaginal tract.

Vaginal fibroma in canines female tract are usually contain the progesterone receptors, these growths if large in size can be treated with aglepristone (10 mg/kg subcutaneously on day 1, 2, 8, 15, 28 and 35, manufacturers detail: Alizin 30 mg/ml, Virbac animal health) for reduction of size and final removal can done with surgical excision effectively. In this case, report as size of growth was smaller and single growth was present, so without any drug it was surgically excised.

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