Surgical treatment of vaginal leiomyosarcoma in a mixed breed dog Lisa Benson Cornell University College of Veterinary Medicine Class of 2014 4/16/14

History 11 year old FS Mixed Breed Dog Presenting Complaint: Mass of the Colon Tenesmus x 2 weeks: 3 Days Lactulose Rapid Growth Cough x 2 weeks Progressive Right Hind Limb Lameness Bilateral Hind Limb Lameness - Chronic

History 11 year old FS Mixed Breed Dog Presenting Complaint: Mass of the Colon Tenesmus x 2 weeks: 3 Days Lactulose Rapid Growth Cough x 2 weeks Progressive Right Hind Limb Lameness Bilateral Hind Limb Lameness - Chronic

Physical exam: Abnormalities Very Nervous Sensitive Hind Limbs/Caudal Trunk Right Hind Limb Lameness: Lateral Extension Left Hind Limb: Firm, Movable Subcutaneous Mass Digital Rectal Palpation Hard, Bony Mass: Left Ventral Pelvic Canal Firm, Rounded Mass: Right Ventrolateral Pelvic Canal Complete Obstruction Painful hindlimbs and caudal trunk—indications. RHL Extension, cranio laterally extended during sitting and recumbency, and SWINGS leg laterally during ambulation

Problem list Chronic, Mild Bilateral Hind Limb Lameness: Lifetime Mass – Pelvic Canal Progressive Right Hind Limb Lameness Tenesmus Cough Left Hind Limb Subcutaneous Mass

Problem list Mass – Pelvic Canal Tenesmus Progressive Right Hind Limb Lameness Cough (?) Left Hind Limb Subcutaneous Mass (?)

Differential diagnoses Broad Pelvic Mass Differential Diagnosis Tumor or Abscess Arising from the Following: 1. Rectum 2. Vagina 3. Urethra 4. Bony Pelvis

Diagnostics Bloodwork: Complete Blood Count/Blood Chemistry: Unremarkable Imaging: Full Body CT Scan Thorax Abdomen Pelvic Canal Proximal Hind limbs

Ct scan: Sagittal image Mass Cranial Caudal Orient! — Sagittal Plane Bladder Heart

Ct scan: Sagittal image Colon Urethra

Ct scan: sagittal image

Ct scan: sagittal image

Ct scan: frontal image Frontal plane

Ct scan: transverse image Transverse Plane

CT Scan: Findings Thorax and Abdomen: Negative for Metastasis Pelvis: Large Mass – Sciatic n. Compression Vaginal Origin – Not Colon Incidental: Left Hind limb Mass: Lipoma Hip and Shoulder Osteoarthritis - Mild BIG PICTURE: LARGE VAGINAL MASS, Likely cause of RH lameness but not her cough. Thorax/Abd: Negative for Mets—Cough no longer big concern—dry heat lately Pelvis: LARGE mass, Inability to defecate attributed to mass left dorsal compression of rectum = Hard bony “mass” left ventral rectum = I really palpated ischium. Ventral displacement of Urethra. Mass Continuous w vagina and unlikely to be arising from rectum. RHL pain was possibly due to Sciatic N. compression LHL SQ mass determined to be a lipoma (Neg for Neoplasia) Osteoarthritis: explains the chronic mild lameness owners noted for most of her life Hip OA was MILD and UNLIKELY cause of RHL pain

Differential diagnoses Vaginal Mass: Neoplasia vs. Inflammation Neoplasia Benign: Leiomyoma Malignant: Leiomyosarcoma Inflammation: Stump Pyometra Less Likely: 10.5 years post Spay No Signs of Ovarian Remnant

Leiomyoma vs leiomyosarcoma Smooth Muscle Tumors: GI more common location Lack of Vaginal Cases and Information 2.4% - 3% of ALL Canine Tumors are from Reproductive System 83% Benign (Leiomyoma Most Common) Intact Females Sometimes metastatic, and if excision was incomplete = indication for RT. We don’t have data on the impact on survival with adjuvant therapy.  “The impact of adjuvant radiation or chemotherapy on outcome is unknown.”  

Leiomyoma vs leiomyosarcoma Leiomyosarcomas – Hormonally Independent Complete Excision (Vaginal): Curative Moderate Risk Metastasis/Recurrence Impact of Adjuvant Radiation/Chemotherapy: Outcome on Survival Unknown Sometimes metastatic, and if excision was incomplete = indication for RT. We don’t have data on the impact on survival with adjuvant therapy.  “The impact of adjuvant radiation or chemotherapy on outcome is unknown.”  

plan Surgery: Mass Excision Episiotomy +/- Abdominal Exploratory Pubic Osteotomy Partial Vaginectomy Histopathology for Definitive Diagnosis

Surgery: Neuroanatomy Pudendal n. Pelvic n. Perineal n. Hypogastric n. Pelvic Plexus Orientation: Cranial; Caudal; Bladder; Desc Colon; Vagina. Hypogastric N. Cranial= sympathetic innervation of the bladder- On LATERAL SURFACE OF RECTUM Pelvic Plexus ON LATERAL SURFACE OF RECTUM comes off of the Pelvic n- (axons SC S1-S3): innervation of bladder, rectum, Urethra (ext sphincters); genitalia. pudendal n. comes off of pelvic plexus moving caudally—Perineal n and a branches off of pudendal n which branches off of the pelvic NERVE (not plexus) Our main concern: Avoid damaging these nerves. Closely associated with the area we’ll be dissecting, to excise the mass completely—potential for permanent urinary incontinence, rectal incontinence (lesser concern?). Also: Risk of perforated bowel: descending colon or rectum may perforate, cause sepsis with anaerobic bacteria. (pre-operative (24 hrs in advance) started oral Clindamycin, continued perioperatively and post operatively IV. Plus TGH oral x 2 weeks. (Evans, de LaHunta)

Surgery: Episiotomy Orientation: Dorsal, Ventral. Standard episiotomy - Full thickness incision. attempt to access tumor and remove it. (Less invasive)

surgery Mass Orange Catheter: Vaginal Canal White Catheter: Urethral Papilla Palpated mass in vaginal canal– too cranial to remove it via episiotomy.

Surgery: Abdominal Colon Random Loop of Intestine Uterine Remnant Orient - Pulled bladder caudally; Find uterine remnant and mass. See that a pelvic approach necessary –it’s smack in the middle of the pelvic canal---Osteotomy! Urinary Bladder

Surgery: Mass located Mass Pubic Symphysis Pulled bladder cranially—urethra, palpable mass continues deep to Pubic Symphysis Pubic Symphysis

Surgery: pubic osteotomy Cleared Pubic Bone: Transected Adductor mm and Gracilis mm with cautery at point of origin along pubic symphysis. Point out holes drilled for orthopedic wire to close pelvis later—22 gauge. Three transections— 2 cranial to caudal cuts: 1 in right and 1 in left arm of pubis, then a transection perpendicular and CRANIAL to the first two . Protected obturator n with miller sens when drilling.

Surgery: Mass Excision Pubic symphysis flipped caudally—See OBTURATOR MUSCLE on inside of the bone, we left intact.Mass easier to visualiize and dissect away from tissues—CAREFUL OF NERVES

SURgery: Mass Excision Pelvic Plexus Mass within vaginal wall. NERVES: Pelvic Plexus —innervating bladder, rectum, urethra. Pudendal n from pelvic n innervating external urethral sphincter. Hypogastric n, sympathetic nerves also along lateral wall of the rectum too—MUST DELICATELY DISSECT AWAY MASS, dissect Vagina off rectum. –incontinence Risk. Compressed (by mass) for a long time!

Surgery: Vaginal Wall Reflected Vaginal Wall reflected—see mass

Surgery: Mass Excision Orient Cranial and Caudal: Almost out!

Surgery: Dissect Carefully Last remnant of attachment to vaginal wall. Vaginal tissue thin, compromised. Partial vaginectomy. Total vaginectomy was not necessary—--avoid possible harm to nerves.

Surgery: repair osteotomy Closed pubic bones with 22 gauge orthopedic wire placed into the predrilled holes- circlage technique to stabilize bony pelvis. Reattached gracilis and adductor muscles. Closed vagina where we’d opened it to get the mass out—mass was attached to dorsal wall. Closed the dorsal (and ventral ) defects of vaginal wall– continuous 3-0 PDS. Repaired 2 cm area of compromised rectal serosa w/3-0 PDS (mass compression). THEN STANDARD ABDOMINAL closure after warm abdominal lavage. SUMITTED TISSUE TO PATHOLOGY…

Surgery: Mass Removed SUBMITTED FOR HISTOPATHOLOGY!

histopathology PALE ISCHEMIC CHANGES (clear spaces BLACK ARROW)) and inflammation: segmented neutrophils (more cellular areas: BLUE ARROW). Loss of cellular and nuclear detail. Small areas of necrosis, hemorrhage, inflammation.

histopathology This slide highlights the disorganization and irregular orientation of neoplastic cells. Smooth Muscle tumors are disorganized , interacting at odd angles. Aniscokaryosis: Nuclei changing from normal cigar shaped nuclei to circular. This tissue is not “calm enough” to be a leiomyoma, though it is acting more ”well-behaved” than some leiomyosarcomas/malignant tumors.

Histopathology: Leiomyosarcoma Blue Arrow: Mitotic Figure. Originally this report was read out as 1-2 MFs per 10 HPF, but reviewed it again and it was more like 3-4 per 10 HPF. –Mild but more than typical leiomyoma. Acting more like a leioMYOMA, but d/t necrosis, inflammation, LACK OF ORGANIZATION, loss of cellular and nuclear detail, anisokaryosis, anisocytosis: which are all features of a MALIGNANT TUMOR: it is not an entirely “nice” benign leiomyoma. Though there is a grey zone and this will likely be a well-behaved tumor. Normal muscle tissue - around tumor’s full circumference, indicating likely fully excised (can’t obtain wide margins in this type location). So it was read out to be a Leiomysarcoma—to err on the side of caution.

Post surgical care Antibiotic: Clindamycin IV 11mg/kg BID Pain Management: Fentanyl CRI 2 mcg/kg/hr  Patch Dexmedetomidine IV 15 mcg PRN Q4h Carprofen 2 mg/kg BID Gabapentin 3 mg/kg BID Tramadol 3 mg/kg PRN Supportive Care: IV Fluids, Ice and Check Tegaderm Q6h BACK TO OUR PATIENT…

Post surgical care Main Concern: Urinary Incontinence Monitor for Urination, Check for Leakage 1 Day Post Surgery: Steady Controlled Stream Discharged That Evening Discharged to her owners after 1 full day in hospital for post operative care. Walked very well, urinated “great stream!” less than 24 hours post surgery.

update 2 week Recheck – Tenesmus Gave Pumpkin and Lactulose Lactulose Overdose  Diarrhea Once Owners “Very Pleased” No Signs Now Bladder Control 7 hours (Reduced) Lactulose PO 5 ml BID Out at midnight and by 7am—Does well, no accidents (BUT 7 hours is her limit—She can’t hold her bladder longer (and she could before surgery). Managed on Lactulose: 5 ml (1 teaspooon) BID. The Owner says he “doesn’t dare” stop for fear of more tenesmus. He has found the right dose—no Diarrhea (No tenesmus—just normal stool).

Costs Combined Total Costs Dollar Amount Administrative Management 697.00 Anesthesia 818.50 Clinical Pathology 67.88 Imaging 832.20 Professional Services 100.00 Hospitalization/Inpatient Care 595.00 All Supplies and Materials 616.55 Pharmacy 199.73 Grand Total $ 3,926.86 Total costs: Just shy of $4,000

references Buergelt, Claus D. Color Atlas of Reproductive Pathology of Domestic Animals. St. Louis: Mosby. 1997. Print. Evans, H., de Lahunta, A. Miller's Anatomy of the Dog. 4th Ed. St. Louis: Elsevier Saunders. 2013. Print. Maxie, M G, K V. F. Jubb, P C. Kennedy, and Nigel Palmer. Jubb, Kennedy, and Palmer's Pathology of Domestic Animals. Edinburgh: Elsevier Saunders. 2007. Print. McEntee, Kenneth. Reproductive Pathology of Domestic Mammals. San Diego: Academic Press. 1990. Print. Nelissen, P, and RA White. "Subtotal Vaginectomy for Management of Extensive Vaginal Disease in 11 Dogs." Veterinary Surgery : Vs. 41.4 (2012): 495-500. Print North, Susan M, and Tania A. Banks. Small Animal Oncology: An Introduction. Edinburgh: Elsevier Saunders. 2009.Print. Thacher, C, and RL Bradley. "Vulvar and Vaginal Tumors in the Dog: a Retrospective Study." Journal of the American Veterinary Medical Association. 183.6 (1983): 690-2. Print. Tobias, Karen M, and Spencer A. Johnston. Veterinary Surgery: Small Animal. St. Louis, Mo: Elsevier. 2012. Print. Weissman A, D Jiménez, B Torres, K Cornell, and SP Holmes. 2013. "Canine Vaginal Leiomyoma Diagnosed by CT Vaginourethrography". Journal of the American Animal Hospital Association. 49, no. 6. Withrow, Stephen J, and David M. Vail. Withrow & Macewen's Small Animal Clinical Oncology. St. Louis: Saunders Elsevier. 2007. Print.

Thank you! Dr. Flanders Dr. Hume Dr. Ruby Dr. Asakawa The Class of 2014 My Family My Advisors, My Class, and My Family