Tumors and tumor-like lesions in the genitalia of sows

Cystic endometrial hyperplasia and uterine adenocarcinoma in two miniature pigs

Due to the increasing popularity of minipigs as pets, the frequency of presentation to the veterinarian is increasing as well. In addition to routine measures such as claw trimming, vaccination and antiparasitic treatment, diagnostics, and therapy of diseased minipigs are also common activities in the veterinary practice. In recent years, we have noticed more and more pathological changes of the female genital tract of uncastrated minipigs. There are also some case reports available in the international literature in this regard. The following case report describes the diagnostic procedures and ovariohysterectomies of 2 13-year-old female minipigs in detail. In these cases, uterine adenocarcinoma, and uterine carcinoma, respectively, combined with cystic endometrial hyperplasia (CEH) of the endometrium were diagnosed.

Surgical treatment of uterine neoplasia in 13 production size pigs with a comparison to pot-bellied pigs

OBJECTIVES

The primary objective of this study was to describe the clinical management and surgical treatment of production size pigs (PrdP) with uterine neoplasia. A secondary objective was to compare tumor diagnoses as well as short- and long-term survival between PrdP and a published report of pot-bellied pigs (PBP) following surgical intervention.

STUDY DESIGN

Retrospective clinical study.

ANIMALS OR SAMPLE POPULATION

Client-owned PrdP (n = 13) treated with exploratory celiotomy ±ovariohysterectomy for uterine neoplasia.

METHODS

Medical records from a university hospital were reviewed for historical treatment, presenting complaint, clinical signs, diagnostics, surgical intervention, pathology, and outcome. An online owner survey was performed for follow-up. The novel PrdP cohort was compared to a previously published PBP cohort for differences in tumor diagnoses, surgical complications, and survival. Descriptive statistics, Fischer's exact tests and odds ratios were reported.

RESULTS

PrdP were affected by uterine leiomyoma (4/11), leiomyosarcoma (2/11), adenoma (1/11), adenocarcinoma (3/11), and carcinosarcoma (1/11) with no difference in tumor types between PrdP and PBP. PrdP surviving to hospital discharge (6/13) survived at least 1 year postoperatively, with median follow-up of 16 months (14-60 months). PrdP were less likely than PBP to survive in the short-term despite similar frequencies of marked intraoperative hemorrhage. PrdP and PBP had comparable rates of long-term survival following hospital discharge.

CONCLUSION

PrdP are afflicted by similar uterine neoplasia diagnoses as PBP, but they have lower rates of short-term survival to hospital discharge with surgical treatment.

CLINICAL SIGNIFICANCE/IMPACT

PrdP have a guarded prognosis for survival to hospital discharge when operated for uterine neoplasia.

Neoplastic lesions in domestic pigs detected at slaughter: literature review and a 20-year review (1998-2018) of carcass inspection in Catalonia

Background

The present paper reviews the occurrence of neoplasms in swine and presents a case series of 56 tumors submitted to the Slaughterhouse Support Network (Servei de Suport a Escorxadors [SESC] IRTA-CReSA]) from slaughtered pigs from 1998 to 2018 (April) in Catalonia (Spain). The aim of the study was to describe the spectrum of spontaneous neoplastic lesions found in slaughtered pigs and to compare the reported tumor cases with previous published data. Lymphoid neoplasms were characterized and classified using the WHO classification adapted for animals.

Results

The most reported neoplasm during this period was lymphoma (28). Within lymphomas, the B-cell type was the most common, being the diffuse large B-cell lymphoma (15/28) the most represented subtype. Other submitted non-lymphoid neoplasms included melanoma (7), nephroblastoma (3), mast cell tumor (2), liposarcoma (2), osteochondromatosis (2), papillary cystadenocarcinoma (1), peripheral nerve sheath tumor (1), lymphoid leukemia (1), fibropapilloma (1), hemangiosarcoma (1), hepatoma (1), histiocytic sarcoma (1), pheochromocytoma (1) and osteosarcoma (1).

Conclusions

The existence of a well-established Slaughterhouse Support Network allowed the compilation of comprehensive data for further epidemiological and pathological studies, particularly about less commonly reported lesions in livestock such as neoplasms in pigs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40813-021-00207-0.

Neoplasia of the tubular genital tract in 42 goats

OBJECTIVE

To assess the prevalence of tubular genital tract neoplasia in does evaluated at 2 veterinary teaching hospitals; describe the main clinical, surgical, and histopathologic or necropsy findings in affected does; and assess factors potentially associated with short-term prognosis in these animals.

ANIMALS

42 does.

PROCEDURES

Medical records of 2 veterinary teaching hospitals were searched to identify does with neoplasia of the tubular genital tract. Signalment; history; physical and diagnostic imaging results; biopsy, surgery, and necropsy findings; and short-term outcome were recorded. Age and breed frequencies for the sample were compared with those of the overall hospital population, and variables of interest were tested for associations with a diagnosis of adenocarcinoma and with short-term outcome by statistical methods.

RESULTS

Median age at hospital admission (10 years) was greater for the study sample than for the general hospital population (2 years). Pygmy goats were overrepresented (22/42 [52%]). Common reasons for evaluation were bloody vaginal discharge or hematuria and abdominal straining. Adenocarcinoma (13/42 [31%]), leiomyoma (13 [31%]), and leiomyosarcoma (11 [26%]) were the most common tumors. Does with distant metastasis had greater odds of a diagnosis of adenocarcinoma (OR, 40.5) than does without distant metastasis. In the analysis adjusted for hemorrhagic discharge, odds of euthanasia for does with straining were 13 times those for does without straining. In the analysis adjusted for straining status, does with hemorrhagic discharge had almost 7 times the odds of euthanasia for does without this finding. The survival-to-discharge rate was low (13/42 [31%]).

CONCLUSIONS AND CLINICAL RELEVANCE

The frequency of adenocarcinomas in the study sample was unexpectedly high. Further research is needed to confirm the study findings.

Uterine Smooth Muscle Tumors in Potbellied Pigs (Sus scrofa) Resemble Human Fibroids: A Potential Animal Model

Uterine leiomyomas, commonly termed fibroids, clinically affect approximately 25% of women of reproductive age in the United States, with a subclinical incidence as high as 77%. The pathogenesis of fibroid formation remains poorly understood, due in large part to the lack of a suitable animal model. This retrospective study characterizes the clinical, gross, and histopathologic features of similar, spontaneously occurring uterine tumors in potbellied pigs. Medical records available through a local Potbellied Pig Spay/Neuter Program, pig sanctuaries, and the Duchess Fund database were reviewed for evidence of reproductive disease or surgery. One-hundred and six female potbellied pigs were evaluated and uterine neoplasia was identified in 17 animals; tissues were available for 13 of these. Uterine leiomyoma was diagnosed in 11 of 13 cases, leiomyosarcoma in 1 of 13 cases, and undifferentiated sarcoma in 1 case. Pigs presented with clinical signs including abdominal distension or vaginal bleeding or were subclinical and identified during ovariohysterectomy. Tumors ranged from microscopic to 45 kg, were often multiple, and primarily involved the uterine horns. Hematoxylin and eosin and trichrome-stained sections were evaluated for morphological features of human and animal leiomyomas; immunohistochemistry to detect smooth muscle actin was also performed. The cellular pattern/morphology and variable degree of fibroplasia of the leiomyomas were similar to that reported for human fibroids. These results support further investigation of uterine leiomyomas in potbellied pigs as a potentially valuable animal model for studying human fibroids.

Metastasizing Oral Squamous Cell Carcinoma in an Aged Pig

A 10-year-old, female, pot-bellied pig (Sus scrofa) experienced a 3-month history of reduced appetite, dysphagia, and weight loss. Clinical examination revealed a mass in the left part of the oral cavity extending from the hard to the soft palate. At necropsy, a firm, white, poorly demarcated ulcerated mass at the left hard and soft palate with metastases to the left retropharyngeal lymph node and the lung was observed. Additional findings included a uterine adenocarcinoma, a hepatocellular adenoma, and nodular hyperplasias in spleen and adrenal glands. Histologically, the poorly demarcated, infiltrative growing oral mass consisted of islands, cords, and single epithelial cells with moderate squamous differentiation. Cells were strongly positive for cytokeratin by immunohistochemistry. Similar cells were found in the left retropharyngeal lymph node and the lung. The present findings represent the first report of a metastasizing oral squamous cell carcinoma in a pig.

Uterine Leiomyomas in Two Vietnamese Pot-bellied Pigs (Sus scrofa)

Two Vietnamese pot-bellied pigs ( Sus scrofa) were euthanatized after they developed abdominal distension. Necropsy of both pigs revealed large myometrial neoplasms and cystic endometrial hyperplasia. Multiple discrete smaller myometrial neoplasms were also observed in one pig; however, distant metastases were not observed in either animal. The tumors were diagnosed as leiomyomas on the basis of histologic examination and immunohistochemistry. This is the first detailed report of uterine leiomyomas in swine, and it is suggested that this diagnosis may become more common as more aging pigs are examined.

Diffuse Cystic Endometrial Hyperplasia and Metastatic Endometrial Adenocarcinoma in a Vietnamese Pot-Bellied Pig (Sus Scrofa)

A 16-year-old female Vietnamese pot-bellied pig was euthanized after a period of inappetence and weight loss. Diffuse cystic endometrial hyperplasia and endometrial adenocarcinoma with metastasis to lymph nodes, liver, and lung were diagnosed. This report follows the recent description of cystic endometrial hyperplasia and uterine leiomyomas in 3 aged female Vietnamese pot-bellied pigs. The findings in this report and previous reports suggest that pigs may develop some similar age-related uterine lesions as do women.

[Uterine neoplasia in two geriatric miniature pet pigs - diagnostics and therapy. Two case reports]

Miniature pet pigs are becoming ever more common among the patients of small animal practices. Due to an advanced age attained in these animals in comparison with conventional pigs in pork production, miniature pet pigs develop age-related diseases that are infrequently observed in farm pigs, including neoplastic alterations of the uterus. We describe two cases of a uterine adenocarcinoma and a leiomyoma, respectively, in two miniature pet pig sows. Options and limits of diagnostic measures (unspecific clinical symptoms, x-ray, sonography and computed tomography) and therapy within the legal limits as well as the risk of an incorrect diagnosis based upon the more common differential diagnoses in swine medicine, including obstipation, cystitis and endometritis, are discussed.

Uterine Lesions in 32 Female Miniature Pet Pigs

Thirty-two 4-month-old to 19-year-old female miniature pet pigs were spayed. Uterine lesions were present in all except 8 pigs. The 24 remaining pigs had diffuse cystic endometrial hyperplasia, of which 14 had smooth muscle tumors, including leiomyomas and leiomyosarcomas, in the uterus or broad ligament. Nodular endometrial lesions—including adenocarcinomas, adenomas, and/or adenomyosis—were present in 10 pigs, 3 of which had concurrent smooth muscle tumors. Pyometra was present in 3 pigs. In uterine sections with cystic endometrial hyperplasia, adenomyosis, or adenomas, approximately 70% of epithelial nuclei expressed estrogen receptor and progesterone receptor immunohistochemically; in adenocarcinomas, expression was 20%. Regardless of malignancy, more than 50% of nuclei in smooth muscle tumors expressed estrogen receptor and progesterone receptor. Aging was associated with the development of uterine lesions in miniature pet pigs.

Expression of steroid receptors and calponin in a cervical leiomyoma in a young pig

Thickening of the uterine cervix and bilateral ovarian cystic change was identified in a 6-month-old pig during routine abattoir inspection. Microscopically, the cervical lesion comprised a non-encapsulated mass of densely packed, large and monomorphic spindle cells within the myometrium. Immunohistochemically, the majority of these neoplastic cells expressed the cytoplasmic terminal smooth muscle differentiation marker calponin, the nuclear oestrogen receptor alpha and the progesterone receptor. The ovarian cysts were classified as follicular cysts. A diagnosis of leiomyoma of the uterine cervix with bilateral ovarian follicular cysts was made. The expression of calponin as a marker of smooth muscle differentiation in tumours of the genital tract of the pig has not previously been reported. The expression of steroid hormone receptors suggests a role for steroid hormones derived from the ovarian follicular cysts in tumourigenesis.

Fibroepithelial hamartoma in a domestic pig

This case report is the first description of a fibroepithelial hamartoma in a pig. The dysplasia, which covered half of the face of the newborn piglet, did not increase in relative size until the animal was euthanatized at 6 months of age. Histologic examination revealed a moderate orthokeratotic hyperkeratosis with variable degrees of epithelial proliferation. The main body of the dysplasia consisted of collagenous fibers. In addition, some proliferating small blood vessels as well as focally gathered dilated apocrine glands were evident. Given morphologic and clinical features, the diagnosis of a hamartoma seemed to be justified.

An update on the use of B-mode ultrasonography in female pig reproduction

After technological advances allowed for the adaptation of B-mode ultrasonography equipment for use in pig facilities, ultrasonography quickly established itself as an ideal diagnostic aid for determining pregnancy status in pigs. In recent years, B-mode ultrasonography has found increased application in its use for monitoring ovarian activity and in estimating time of ovulation in pigs. B-mode ultrasonography is also valuable in providing a detailed assessment of the sow's ovaries and uterus to determine if pathological conditions exist, which could be contributing to poor individual or herd reproductive performance. In its most recent application in pigs, the gilt genital tract has been characterized peripubertally by ultrasonography in order to detect onset of puberty. The purpose of this review is to provide an update on the current status of B-mode ultrasonography in pig reproduction, and how this technology can be of value when used in pig production medicine.

Genital tract smooth muscle tumors are common in zoo felids but are not associated with melengestrol acetate contraceptive treatment

In a survey of gynecologic lesions in female zoo felids conducted to determine if the widely used progestin contraceptive melengestrol acetate (MGA) had adverse effects, numerous leiomyomas and leiomyosarcomas were detected. This current study aimed to characterize the morphologic features of these tumors, determine their prevalence, and assess if MGA was a risk factor for their genesis. Genital tracts from 219 zoo felids representing 23 species were evaluated, and leiomyomas were detected in 24% of the felids. Leiomyomas were often multiple and occurred in the myometrium, ovary, or adjacent broad ligament. The risk of developing leiomyomas increased with age, but MGA treatment or parity had no effect. Five other felids had leiomyosarcomas. Leiomyosarcomas were distinguished from poorly demarcated leiomyomas by the presence of local invasion, metastasis, and cellular atypia, but necrosis and mitotic rate were not distinguishing criteria. Four of five felids with leiomyosarcomas had been treated with MGA. These results indicate that leiomyomas are common spontaneous lesions in the genital tracts of zoo felids and their genesis is not linked to MGA exposure. Whether progression to malignancy is promoted by MGA warrants further investigation.

Fibroleiomyomas of the tubular genitalia in female beluga whales

Fibroleiomyomas of the tubular genitalia were diagnosed in 6 of 9 adult female beluga whales from the St. Lawrence estuary, Quebec, Canada. These tumors were located in the vagina (6 of 6), the cervix (2 of 6), and the uterus (1 of 6). Endogenous hormones or xeno-estrogens may be implicated in the occurrence of these tumors.

Evaluation of reproductive failure of female pigs based on slaughterhouse material and herd record survey

Reproductive organs were collected from one slaughterhouse and culling data were obtained from Finnish swine herd records to determine the types and frequencies of various fertility disturbances in Finnish female pigs. Detailed information about the type and occurrence of fertility disturbances was obtained through a close examination of the slaughterhouse material. A total of 1708 reproductive organs of female pigs were examined. The following findings were recorded: no macroscopical abnormalities 52.3%, inactive ovaries 25.1%, parovarian cysts 22.9%, single ovarian cysts 3.1%, multiple ovarian cysts 3.1%, uterine disorders 1.4%, ovarian adhesions 1.1%, congenital anomalies 0.8%, tumour-like lesions in ovaries 0.8%, obstruction of oviduct 0.2%, and suppurative ovarian infection 0.1%. A large proportion, 42% of the culled gilts and 39% of the culled sows, were slaughtered because of impaired fertility based on no pregnancy, no heat or poor piglet production. The sows were removed from the herds 33 days on average after weaning.