Tuesday, December 6, 2016

Discharge Instructions and Notes from Radiation Treatment at TAMU

VETERINARY MEDICAL TEACHING HOSPITAL
TEXAS A&M UNIVERSITY ONCOLOGY
REFERRAL LETTER/DISCHARGE INSTRUCTIONS

PATIENT: Kisses ADMISSION DATE: December 06, 2016

ATTENDING CLINICIAN:
Jed Darden, DVM
SENIOR CLINICIAN:
Claudia Barton, DVM
STUDENT: Sarah Irving

PROBLEM(S) FOR WHICH PATIENT WAS PRESENTED:

Squamous Cell Carcinoma - Strontium treatment

HISTORY: Kisses is a nine-year-old female spayed domestic medium-haired cat presented to Texas A&M Oncology for strontium plesiotherapy. Kisses became lethargic in August. Around that time, a mass was noted on her lower right eyelid. She was taken to an ophthalmologist, who biopsied the lesion. On histopathology, the lesion was diagnosed as an incompletely-excised squamous cell carcinoma. Approximately one month ago, another tiny ulcerated area was noticed on the outside of her upper left pinna. The tiny lesion was dark and scabbed over; it has not yet been aspirated or biopsied. Kisses was taken to Dr. Parsons-Doherty at North Houston Veterinary Specialists, who referred Kisses to Texas A&M for strontium plesiotherapy.

Kisses has been doing well overall. She has been eating and drinking normally. Kisses eats 1/8 cup of Science Diet adult kibble 4 to 6 times a day. She seems to be urinating and defecating normally, and normally urinates and defecates outside. Kisses is a mainly indoor cat who lives with two Italian Greyhounds. Kisses had bloodwork performed that showed a neutropenia; she is FeLV and FIV negative. She was given an injectable antibiotic and then was placed on four weeks of oral liquid Clavamox, which was completed one week ago. After the biopsy, Kisses was squinting and blinking more than normal and was stumbling when she jumped. She was placed on buprenorphine (0.05 mL, 0.6 mg) once or twice a day as needed. She was also prescribed imiquimod cream to place on the lesions, but Kisses received only three treatments; the cream was applied twice on November 29, 2016 and once on November 30, 2016. The area appeared more irritated and crusty, so the medication was discontinued by Ms. Orgill. Kisses also refused to eat while wearing an elizabethan collar but would eat when the collar was removed.

PHYSICAL EXAMINATION:

Weight: 3.17 kg; Body Condition Score: 5/9; Pain Score: 1/5
Temperature: 101. 4 F; Pulse: 200/min; Respiration: 34/min
Electrocardiogram: Normal sinus rhythm
Attitude: Bright, alert, responsive; euhydrated
Mucous membranes: Pink, moist, CRT < 2 sec
Cardiovascular: Normal sinus rhythm detected; no murmur ausculted; femoral pulses strong and synchronous with heart beat
Respiratory: Eupneic; normal bronchovesicular sounds bilaterally; no crackles/wheezes
Ocular: Mild serosanguinous discharge from the biopsy site over the right eyelid; pupils equal and reactive; no significant abnormalities of the globe of the eyes; right lower eyelid was ulcerated and had a triangular divot from the previous biopsy; right lower eye was thickened and swollen.
ENT: Facial expression symmetrical; teeth were clean, upper left canine tip is fractured off with no pulp cavity visible; ears – clean, no odor or discharge; small black lesion on left pinna
Integument: Hair was clean, shiny, and full; skin – no masses, lesions or erythema present; no ectoparasites
Gastrointestinal: Abdomen was soft and non-painful on palpation; no appreciable fluid-wave; no overt organomegaly detected
Genital: Digital rectal examination was not performed.
Neurologic: Normal mentation; normal posture; no ataxia; all cranial nerves intact and normally elicited; a full neurological exam was not performed.
Musculoskeletal: Ambulation was not examined; no lameness reported by the owner; no joint effusion or pain on long bone palpation noted on cursory examination; well-muscled and symmetrical
Lymph nodes: Peripheral lymph nodes palpate smooth, soft, and symmetrical.

DIAGNOSTIC TESTS & RESULTS: None performed today with TAMU Oncology
DIAGNOSIS: Squamous cell carcinoma, right lower eyelid
TREATMENTS: Strontium-90 treatment to the lower right eyelid and to the tiny lesion on
the left dorsal pinna

ALL CURRENT MEDICATIONS

  • Continue current medications as prescribed by previous veterinarians, but do not continue the imiquimod cream, since it can be irritating.
  • Please keep Kisses in her e-collar when she is not being monitored by you at home. It will be important to keep her from irritating the site of plesiotherapy. Self-mutilation of her eyelid by her paws tends to be the biggest issue post therapy and can delay the healing process.
  • Recheck blood work is vitally important to your pet's health, since white blood cell counts or platelet counts that are too low can lead to serious complications up to and including death. For this reason, we cannot refill chemotherapy prescriptions unless results of blood work are available to us. Please make sure that you arrange to have your pet's blood work performed in advance with enough time to have results emailed to us at oncology@cvm.tamu.edu or faxed to us at 979-458-4444.

Please note: We are unable to refill any medications for a patient that has not been examined by our department in over 3 months. Please allow up to 3 business days for medication refills to be authorized. Certain requirements (lab work, recheck examination) may be necessary in order for us to process a refill. We cannot process refills for medications we did not originally prescribe. Please see your discharge paperwork for more information.

PLAN FOR RE-EVALUATION:

Please schedule an appointment with Dr. Parson-Doherty in 10-14 days to recheck Kisses' radiation site. She will be checking for any radiation side effects; by that time, there may be some inflammation of the site prior to healing and she will then make a decision as to whether any other treatment is necessary.

Please schedule an appointment with Dr. Parsons-Doherty in one month if the ulcerated area on Kisses' lower eyelid has not healed completely; if there is still an ulcer at the end of a month, and if the area is not healing, it might be that the tumor was too deep for one strontium treatment to be curative. At that appointment, Dr. Parsons-Doherty will re-evaluate Kisses' treatment area to determine whether she needs any additional strontium treatments. If another treatment is needed, we would need to have some more bloodwork performed to anesthetize Kisses for same-day treatment.

SPECIAL INSTRUCTIONS FOR OWNER: As you know, Kisses has been diagnosed with squamous cell carcinoma (SCC) of the lower right eyelid. This is a malignant tumor of the epidermal cells of the skin; it can occur in people and all domestic species. These tumors develop in areas of skin most exposed to sunlight (UVA and UVB radiation) which causes non-lethal, multi-step genetic damage of cells (mutations in the DNA nucleic acid genome), with failure to repair the damaged DNA. In cats, these tumors affect the non-pigmented areas of the skin, with predilection sites on the ear tips, external nares (nose), lightly haired skin in front of the ears, and eyelids. SCC is a common tumor in white cats and cats with white faces; cats with white hair and skin have an increased incidence of this tumor because they are lacking black and brown pigment in their skin that acts as a physical barrier and a UV radiation filter. SCCs are likely to be erosive and ulcerated. They may become inflamed or may be crusted and bleeding. Eventually, malignant cancers may spread to the local lymph nodes, which become enlarged as a result. Metastasis to other tissues would be unusual for this particular type of cancer, assuming that it is induced by exposure to UV light; spread of those tumors occurs only very rarely.

Unfortunately Kisses's cancer involves her lower right eye lid. Surgery of the eyelid to remove that much tissue would be very difficult and might mean that she would have difficulty closing her right eyelid afterwards---and that might ultimately result in having to remove her eye. For this reason, radiation treatment with strontium-90 is a much better option if it is successful. Strontium-90 treatments are delivered with an applicator that is placed directly onto the area of the tumor for a few minutes until the treatment dose is reached. Patients are placed under general anesthesia to facilitate the administration of this radiation; they must stay still during the entire treatment. The applicator delivers a strong dose of radiation that can effectively penetrate only about 3 mm deep into the tissue, so it treats just the area that is contacted by the probe. The maximum dose of radiation is delivered to the skin surface, with a rapid decrease in the amount of radiation delivered as the depth increases. Less than 10% of the surface dose provided by the probe can be delivered to tissues deeper than 3 mm. Direct application of the probe to the tumor surface helps to spare and preserve the non-cancerous healthy tissue surrounding the tumor. Good results have been achieved with treatment of many cats with superficial SCCs; in one study, 88% of treated cats had a complete response, with disappearance of the tumor. However, some required more than one treatment.

Complications following strontium-90 treatment are not common. Some cats experience a moderate to (rarely) marked amount of inflammation at the treated site, and some can develop infections in that area. If you see any abnormal non-clear (especially greenish, as would be seen with pus) discharge over the site, please have Dr. Graham take a look at the area, since an antibiotic ointment might be necessary.

There is always a small chance that, when healing occurs, scar tissue may develop in Kisses' lower eyelid. This might make the lower eyelid function inappropriately. However, this is not seen often as a major side effect.

Many cats with these tumors will have tumor response after only one treatment. However, depending on how deep Kisses' tumor penetrates into the tissues, additional treatments may be necessary. Thus, rechecking with Dr. Parsons-Doherty at two and four weeks after the treatment would be strongly recommended.

Please remember that other areas on Kisses' face might develop SCC in the future, including her ears (especially the margins), the lightly-haired areas in front of the ears, the pink part of her nose, or her other eyelids. These would be independently developing tumors caused by UV-light exposure to other areas of her face.

Thank you for allowing us to care for Kisses, and please let us know if there is any other way we can help.

Sincerely,

Claudia Barton, DVM, Diplomate ACVIM (Oncology and Internal Medicine)
Heather Wilson-Robles, DVM, Diplomate ACVIM (Oncology)
Kenita Rogers, MS, DVM, Diplomate ACVIM (Oncology and Internal Medicine)
Jesse Grayton, DVM (Oncology)
Michael Deveau, MS, DVM, Diplomate ACVR (Radiation Oncology)
Jacqueline Bloch, DVM, Medical Oncology Resident
Kendra Lyons, DVM, Medical Oncology Resident
Carrissa Wood, DVM, Medical Oncology Resident
Jaci Christensen, BS, LVT, Oncology Technician
Linda Knight, LVT, Radiation Oncology Technician
Harmony Peraza, Oncology Technician
Liz Wood, LVT, Oncology Technician