Cancer, Masses & Lumps

Signs of cancer are highly variable depending on the tumor type and location. Common warning signs that deserve prompt evaluation include:

• A new lump, bump, or swelling anywhere on or under the skin — especially one that changes size over weeks
• A wound or sore that fails to heal
• Unexplained weight loss or muscle wasting
• Loss of appetite and lethargy persisting more than a day or two
• Abnormal bleeding or discharge from any body opening
• Difficulty breathing, swallowing, or eating
• Lameness or swelling over a bone without a clear injury (bone tumors can mimic arthritis)
• A distended or painful abdomen
• Straining to urinate or defecate
• Changes in behavior, vision, or coordination (brain tumors)

Many of these signs are caused by non-cancerous conditions too — which is exactly why a thorough work-up matters more than guessing based on appearance alone.

Cancer develops from a combination of genetic predisposition, environmental exposures, and aging-related DNA damage. Risk factors include:

• Age — the risk of most cancers rises sharply after age seven in dogs and nine in cats
• Breed — certain dog breeds carry dramatically elevated cancer risks: Golden Retrievers (hemangiosarcoma, lymphoma, mast cell), Boxers (mast cell, lymphoma, brain tumors), Bernese Mountain Dogs (histiocytic sarcoma), Rottweilers (osteosarcoma)
• Reproductive status — intact female dogs have a significantly higher risk of mammary tumors, and intact male dogs have higher rates of testicular and prostate cancers
• Chronic inflammation — long-standing skin infections, sun damage on pale skin, or chronic wounds can predispose to certain tumor types
• Secondhand smoke and certain environmental chemical exposures have been associated with nasal and bladder cancers in dogs
• Feline leukemia virus (FeLV) — a major risk factor for lymphoma and other cancers in unvaccinated cats with outdoor exposure

The goal of diagnostic work-up is to answer three questions: What is it? How aggressive is it? Has it spread? Our toolkit includes:

• Fine-needle aspiration (FNA) cytology — a quick, low-cost, minimally invasive first step; a small needle samples cells from the mass, which are examined under a microscope; gives a presumptive answer in many cases on the same day
• Excisional or incisional biopsy — removes tissue for formal pathology; provides definitive diagnosis, grade, and margin assessment; performed by Dr. Alan Schulman
• Complete blood panel and urinalysis — screens for systemic effects of cancer (anemia, abnormal calcium, clotting disorders)
• Chest X-rays — standard screening for lung metastasis before any surgical procedure
• Abdominal ultrasound — evaluates internal organ involvement and lymph node size
• CT scan — our on-site CT provides detailed imaging of chest, abdomen, and bones for staging complex cases without an off-site referral

Cancer treatment is not one-size-fits-all; a plan is built around tumor type, stage, the individual patient's health, and the owner's goals:

• Surgery — the primary treatment for most solid tumors; complete surgical removal (wide margins) is curative for many localized cancers; Dr. Schulman's oncologic surgery expertise guides margin planning and reconstruction when complex anatomy is involved
• Chemotherapy — used for systemic cancers (lymphoma, leukemia), high-grade tumors at risk for metastasis, or as adjuvant therapy after surgery; protocols vary from weekly injectable to monthly oral regimens; most pets tolerate veterinary chemotherapy with far fewer side effects than humans experience
• Palliative and supportive care — pain management, appetite support, and anti-nausea therapy to maintain quality of life when cure is not the goal; can be highly effective for months
• Watchful waiting — for some slow-growing, low-risk tumors (certain lipomas, small benign skin masses in senior patients) monitoring with periodic FNA is a reasonable approach

Specialist oncology referral is coordinated when radiation therapy or advanced protocols are indicated — we prepare the full diagnostic package so a referral visit is immediately productive.

Any new lump that has appeared or grown in the past four to six weeks deserves a same-week appointment for aspiration. Waiting and watching without sampling is rarely the right answer — even a benign result gives peace of mind, and a malignant result caught early means more options. Pets showing systemic signs — weight loss, persistent fatigue, difficulty breathing — need evaluation promptly. Our Calabasas team can aspirate, image, and stage many cancers without sending you elsewhere first, saving time when it matters most. Book an appointment today.