[{"Title":"Apocrine Gland Tumors of the Anal Sac","UniqueID":"v3207496","Index":1.0,"Summary":"

These tumors most commonly appear as deep, firm, masses near the anal sacs. Older English Cocker Spaniels, Springer Spaniels, Dachshunds, Alaskan Malamutes, German Shepherds, and mixed-breed dogs are most at risk. As the tumors grow, they may compress the rectum and induce constipation. Some of these tumors are associated with a syndrome that is characterized by abnormally high calcium in the blood. Elevated calcium causes poor appetite, weight loss, kidney disease, and increased water intake and urine output. The tumors often spread to local lymph nodes and other organs. In most cases, surgery requires removal of the mass and tissues surrounding it, including involved lymph nodes. If the entire tumor cannot be removed, reducing the size of the tumor can help improve signs. Chemotherapy and radiation treatment may also be provided. Few dogs live more than a year after this type of tumor has been diagnosed.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Basal Cell Tumors and Carcinomas","UniqueID":"v3207500","Index":2.0,"Summary":"

Basal cells lie at the base of the top layer of the skin (the epidermis). A benign growth of these cells is a basal cell tumor. A malignant growth is a basal cell carcinoma.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Benign Fibroblastic Tumors","UniqueID":"v3207508","Index":3.0,"Summary":"

Collagenous nevi are benign collections of fibrous proteins known as collagen. They are common in dogs. Generally collagenous nevi are found in middle-aged or older animals, most frequently on the legs, head, neck, and areas prone to trauma. They are flat to raised lumps that develop in the skin or fat beneath the skin. Surgical removal of both forms is generally effective. Infrequently, some may grow too large to be surgically removed.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Benign, Nonviral, Wart-like Tumors","UniqueID":"v3207519","Index":4.0,"Summary":"

These tumors look a lot like warts, but they are not caused by a virus like true warts (papillomas). These tumors are often easy to remove and there is little threat to the overall health of the dog. For information on viral warts, see below.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Blood Vessel Tumors","UniqueID":"v3207530","Index":5.0,"Summary":"

Blood vessel (vascular) tumors of the skin and soft tissues are growths that closely resemble blood vessels. Some forms are benign while others are highly malignant.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Cornifying Epitheliomas","UniqueID":"v3207540","Index":6.0,"Summary":"

Other names for these benign tumors of dogs include keratoacanthoma and infundibular keratinizing acanthoma. These growths are nests of tough, layered lumps that stick up from the skin surface. They can look a little like a horn, which is why they are described as cornifying. In other cases, the epitheliomas may appear solely as cornified cysts. They most likely arise from a hair follicle. These tumors can develop anywhere on the body, but they occur most frequently on the back, tail, and legs. Middle-aged dogs are most at risk. Norwegian Elkhounds, Belgian Sheepdogs, Lhasa Apsos, and Bearded Collies are most likely to develop these tumors. Norwegian Elkhounds and Lhasa Apsos are at risk for developing widespread tumors. The condition is diagnosed by finding the tumors on the animal. Treatment is optional, provided there is no self-trauma, ulceration, or secondary infection. Some dogs find the tumors annoying and attempt to scratch, rub, or bite them off. This leads to skin trauma that can easily become infected. Surgical removal is the treatment of choice. However, dogs are prone to develop additional tumors. For animals with a generalized form of the disease, oral retinoid medications may help.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Hair Follicle Tumors","UniqueID":"v3207546","Index":7.0,"Summary":"

Trichilemmomas are rare, benign, hair follicle tumors of dogs, most commonly found on the head. Poodles may be predisposed. They appear as firm, oval masses, 0.4 to 2.75 inches (1 to 7 centimeters) in diameter that are compact but gradually grow.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Histiocytic Cell Tumors","UniqueID":"v3207555","Index":8.0,"Summary":"

These tumors form a group of poorly defined skin diseases all characterized by a proliferation of cells called histiocytes (tissue macrophages). The cause for these diseases is unknown.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Keratinized Skin Cysts","UniqueID":"v3207563","Index":9.0,"Summary":"

Some dogs develop cysts that are filled with keratin, a skin protein. Such cysts have a hard or solid core. The most common type of cyst contains a gray, brown, or yellowish, granular, “cheesy” material. Most are malformations of hair follicles. There are several kinds of keratinized skin cysts, each of which affect a different part of the hair follicle. The ones found in dogs include infundibular follicular cysts, isthmus catagen cysts, matrix cysts, hybrid cysts (panfollicular cysts), and dermoid cysts. Dermoid cysts are congenital (the animal is born with them). Among dogs, they are most commonly found in Boxers, Kerry Blue Terriers, and Rhodesian Ridgebacks. Most dermoid cysts are multiple and contain fully formed hair shafts. Diagnosis is by finding the cysts on the dog. They can be solitary or multiple and are benign. Surgical removal is the best treatment. You should not to attempt to remove the cysts by squeezing them because this can spread the cyst contents into the surrounding tissues. Your dog’s body will react to the cyst contents as a foreign substance, which can cause severe inflammation.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Lipomas and Liposarcomas","UniqueID":"v3207572","Index":10.0,"Summary":"

Lipomas are benign tumors of fat (adipose tissue) and are common in dogs. Lipomas generally occur in older, obese females, most commonly on the trunk and near the tops of the legs. The breeds most at risk are Doberman Pinschers, Labrador Retrievers, Miniature Schnauzers, and mixed-breed dogs. Lipomas typically appear as soft, occasionally thin, discrete lumpy masses; most move freely when touched. A rare variant of this tumor, diffuse lipomatosis, has been identified in Dachshunds, in which virtually the entire skin is affected, resulting in prominent folds in the skin on the neck and trunk.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Lymphoid Tumors of the Skin","UniqueID":"v3207591","Index":11.0,"Summary":"

Canine extramedullary plasmacytomas are relatively common skin tumors in dogs. They are most frequently identified on the head, ears, lips, mouth, and legs of mature to aged animals. Cocker Spaniels, Airedales, Scottish Terriers, and Standard Poodles are most at risk. The tumors are generally small (less than 2 inches [5 centimeters]) in diameter and sometimes narrow. Diagnosis is by finding the tumors on the animal and confirming the type of tumor with a fine needle aspiration or a biopsy. Most of these tumors do not spread and surgical removal is the usual treatment. When these tumors develop in the mouth, they may multiply. Treatment for the multiple form is more difficult, because the tumors are more likely to return following surgery. In such cases, tissue around the tumors may have to be removed. When tumors are multiple, or surgical removal is not feasible, radiation treatment is considered. Chemotherapy is commonly recommended for patients if radiation treatment is declined or if the tumor is resistant to radiation treatment.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Mast Cell Tumors","UniqueID":"v3207604","Index":12.0,"Summary":"

Mast cell tumors are named for the type of cell from which they grow. Mast cells are involved in allergic reactions. They release histamine, which causes irritation and itching, and other chemicals that may cause shock. Mast cell tumors are the most common malignant tumor seen in dogs. They may be seen in dogs of any age but occur most commonly in dogs 8 to 10 years old. They may develop anywhere on the body surface as well as in internal organs, but the limbs (especially the back of the upper thigh), lower abdomen, and chest are the most common sites. In about 10% of cases, tumors are found in multiple locations. Tumor size at the time of surgery often predicts the outcome; tumors larger than 1¼ inches (3 cm) are associated with decreased survival time. Tumors located near mucous membranes, feet, prepuce, or on the lower surface of the body are more likely to spread than mast cell tumors in other areas. Tumors that grow rapidly or that are not removed completely during surgery are also more likely to spread. Many breeds appear to be prone to the disease, especially Boxers and Pugs (in which tumors are often multiple), Rhodesian Ridgebacks, and Boston Terriers.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Melanomas","UniqueID":"v3207621","Index":13.0,"Summary":"

A melanoma is a dark-pigmented skin tumor that may be either benign (not cancerous) or malignant (cancerous). Benign melanomas (also called melanocytomas) are diagnosed much more frequently in dogs than malignant melanomas. They most commonly develop on the head and forelimbs in middle-aged or older dogs. Miniature and Standard Schnauzers, Doberman Pinschers, Golden Retrievers, Irish Setters, and Vizslas are the breeds in which these tumors are most commonly found. They can appear as spots or patches, or raised or flat masses. Most have a dark surface. Although generally solitary, melanomas may be multiple, especially in the breeds at risk. When these tumors are benign, surgical removal cures the condition.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Perianal (Hepatoid) Gland Tumors","UniqueID":"v3207629","Index":14.0,"Summary":"

Perianal gland tumors are a type of tumor found near the anus in dogs. They occur mostly in oil glands found around the anus. They may also occur in similar glands along the abdomen from the anus to the base of the skull, the tail, and in the skin of the back and areas near the tail. The tumors occur in male dogs three times more often than in females. They are most common in aged dogs. Siberian Huskies, Samoyeds, Pekingese, and Cocker Spaniels are the breeds most commonly affected.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Peripheral Nerve Sheath Tumors","UniqueID":"v3207638","Index":15.0,"Summary":"

There are several tumors that arise from the connective tissue that provides a covering for nerves. These include amputation neuromas, neurofibromas, and neurofibrosarcomas.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Sebaceous Gland Tumors","UniqueID":"v3207649","Index":16.0,"Summary":"

The sebaceous glands secrete the oil known as sebum into the hair follicles and onto the skin. Tumors of sebaceous glands are common in dogs.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Smooth Muscle Tumors of the Skin","UniqueID":"v3207662","Index":17.0,"Summary":"

These tumors (called leiomyomas or leiomyosarcomas) occur rarely in the skin and little is known about them. Those that have been reported have been malignant and found in dogs and cats. In most cases, these are firm masses that can be felt through the skin. Treatment is surgery to remove the tumor. Chemotherapy may also be recommended.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Soft Tissue Giant Cell Tumors (Fibrous Histiocytomas)","UniqueID":"v3207666","Index":18.0,"Summary":"

These tumors are not well understood. They appear more like an inflammatory reaction than a tumor and are generally treated with steroids. An abnormality called canine fibrous histiocytoma has been found in the eye of some dogs, most commonly Collies 2 to 4 years old.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Soft Tissue Sarcomas","UniqueID":"v3207674","Index":19.0,"Summary":"

Sarcomas are a group of connective tissue tumors that often rapidly invade surrounding tissues but are less likely to spread to other sites in the body. Sarcomas on the surface of the skin tend to be benign. Deep sarcomas tend to be malignant. The larger the tumor, the more likely it is to be malignant. A rapidly growing tumor is more likely to be malignant than one that develops slowly. Benign tumors have few blood vessels, whereas most malignant tumors have many blood vessels.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Squamous Cell Carcinomas","UniqueID":"v3207686","Index":20.0,"Summary":"

Squamous cell carcinomas are malignant tumors. They can be found in all domestic animals. In dogs, these are the most frequently diagnosed carcinomas of the skin. Two forms occur in dogs—skin and subungual. Skin squamous cell carcinomas are tumors of older dogs. Bloodhounds, Basset Hounds, and Standard Poodles are at greatest risk. They appear on the head, lower legs, abdomen, and rear. Most appear as firm, raised, frequently ulcerated patches and lumps. Sometimes they can grow outward with a surface like a wart. Some are caused by prolonged sun exposure. These usually develop on the lower abdomen, especially on or near the pubic area in white-skinned, shorthaired breeds such as Dalmatians, Pit Bull Terriers, Bull Terriers, and Beagles. They develop on the underside of dogs because the poorly haired skin offers minimal shielding from ultraviolet radiation. Many animals sun themselves lying on their backs. They also get some solar radiation that reflects from the ground. Before a malignant tumor develops, dogs develop solar keratosis. Solar keratosis is thickened and discolored skin. Thus, finding areas on your dog where the skin is thick and discolored is cause for a veterinary checkup. Early diagnosis is important for successful treatment.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Sweat Gland Tumors","UniqueID":"v3207697","Index":21.0,"Summary":"

There are 2 types of sweat glands in dogs, called apocrine and eccrine. In domestic animals, all hair follicles have apocrine glands, as do anal glands and ceruminous glands in the ears.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Tumors Originating Outside the Skin (Metastatic Tumors)","UniqueID":"v3207714","Index":22.0,"Summary":"

All malignant tumors, wherever they originate, are capable of spreading to the skin. However, the spread of a primary tumor from inside the body to the skin is unusual. Although the appearance is variable, the tumors that spread to the skin are usually multiple, ulcerated lumps. As these tumors grow, they extend deeper into the skin and surrounding tissue. Generally, it is difficult to identify the primary tumor based on the signs in the skin. This is because only a small population of cells in the primary tumor will spread to the skin, and these cells may have different microscopic features than the primary tumor. When tumors have spread from other areas of the body to the skin, the primary tumor usually grows and spreads quickly and the outlook for a positive outcome is guarded to poor. Treatment for these tumors involves a whole-body approach that deal with both the skin tumors and the primary tumor(s).

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Undifferentiated and Anaplastic Sarcomas","UniqueID":"v3207717","Index":23.0,"Summary":"

These are cancers of mesenchymal cells. Mesenchymal cells are the cells that develop into connective tissues, blood, lymph nodes, and other organs. Cancers of mesenchymal cells are difficult to identify because, like the mesenchymal cells themselves, malignant forms of these cells are loosely organized and often undeveloped or undifferentiated. Once identified, surgery is the usual treatment. When removing these cancerous cells, the veterinarian will usually remove not only the visible tumor but also a wide margin of tissue surrounding it. This reduces the chance that the malignancy will recur.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"Warts (Papillomas)","UniqueID":"v3207722","Index":24.0,"Summary":"

Warts are caused by papillomaviruses. The virus is transmitted by direct contact or by contact with contaminated items such as bedding, clothing, dishes, and other items in the dog’s environment. It is also possible that insects may spread papillomaviruses. There are several distinct papillomaviruses. Warts have been reported in all domestic animals and are most common in dogs and horses.

","HeadType":"F_Head","SchemeItemProp":"","Children":[]},{"Title":"For More Information","UniqueID":"v34424984","Index":25.0,"Summary":"

Also see professional content regarding skin tumors Overview of Tumors of the Skin and Soft Tissues in Animals $\"Overview$ .

","HeadType":"F_Head","SchemeItemProp":"","Children":[]}]