cisplatin for malignant effusion (Moore et al. 1991a; Olsen et al. 1994). Platinum drugs with tamoxifen is used in metastatic human ovarian tumors. Chemotherapy has the potential to prolong life in animals with metastatic ovarian cancer.
Uterine Carcinoma
Uterine ADC: Treatment is ovariohysterectomy. Role and effectiveness of radiation and chemotherapy are unknown. Squamous cell carcinoma (SCC) of the uterine remnant in a spayed cat has been reported (Hayashi et al. 2013). Uterine remnant ADC and abdominal metastases have also been reported in a spayed cat (Anderson and Pratschke 2011). Endometrial ADC and mucometra in a dog chronically treated with medroxi‐progesterone acetate have been reported (Pena et al. 2006).
Vaginal and Vulval Tumors
Most are benign (leiomyoma and fibroma in cat and leiomyoma and lipoma in dog).
Insulinoma
Modalities include surgery: for resection of primary (preferably partial pancreatectomy rather than enucleation), for staging, and for debulking metastases. Medical management includes frequent feeds, prednisolone, streptozotocin (serious adverse effects reported by Northrup et al. (2013), diazoxide, and octreotide (Leifer et al. 1986; Tobin et al. 1999; Moore et al. 2002; Feldman and Nelson 2004; Robben et al. 2006). Perioperative glucose levels must be managed. A MST of 381 days for dogs that underwent partial pancreatectomy compares to 74 days reported for dogs treated with medical therapy alone (Tobin et al. 1999). Nineteen dogs treated with partial pancreatectomy had a MST of 785 days and dogs treated with prednisolone therapy on relapse had a MST of 1316 days (Polton et al. 2007). Paraneoplastic superficial necrolytic dermatitis has been reported in a dog (Isidoro‐Ayza et al. 2014). Insulinoma is rare in cats; prolonged survival was reported in one cat treated with surgery alone (Greene and Bright 2008).
Thyroid Carcinoma
Dogs: when tumor is mobile, thyroidectomy (Carver et al. 1995; Klein et al. 1995; Panciera et al. 2004), bilateral thyroidectomy with preservation of at least one parathyroid gland reported (Fukui et al. 2015). Bilateral thyroidectomy for mobile, discrete masses has good prognosis (MST 38.3 months), even without preservation of parathyroids, however, supplementation of thyroxine, calcium, calcitriol is required (Tuohy et al. 2012). In another study, the MST for unilateral thyroidectomy was 1462 days compared with 365 days for bilateral thyroidectomy, and MST for dogs with clinical signs for <35 days was 1677 days, and 391 days for dogs with clinical signs for greater than >35 days (Nadeau and Kitchell 2011). Others report the MST after thyroidectomy is around 3 years if the tumor is freely movable and 6–12 months if the tumor is more invasive (Carver et al. 1995; Klein et al. 1995). For fixed/non‐resectable thyroid carcinoma radiation therapy gives 80% 1‐year survival, 72% 3‐year survival (Theon et al. 2000), and MST of 22–24 months (Brearley et al. 1999; Pack et al. 2001). Post‐radiation hypothyroidism was reported (Kramer et al. 1994; Pack et al. 2001; Amores‐Fuster et al. 2015). 131I thyroid ablation can give prolonged survival in dogs with fixed/non‐resectable thyroid carcinoma, with local/regional tumor MST at 839 days and MST 366 days for metastasis (Peterson et al. 1989; Adams et al. 1995; Panciera et al. 2004; Worth et al. 2005; Turrel et al. 2006). Two studies have shown palpation is not always an accurate predictor of local invasiveness (Taeymans et al. 2013; Campos et al. 2014). In one study, 44 dogs were treated by thyroidectomy (MST 22 months, tumor mobility was recorded in 36 dogs; 27 dogs had freely movable tumors and 9 had fixed tumors; thyroidectomy was unilateral in 42 dogs, bilateral in 1 dog, and 1 dog underwent surgical excision of an ectopic thyroid tumor ventral to the larynx.), 3 dogs underwent debulking (MST 10 months), 4 dogs were treated with thyroidectomy and 131I (MST 13 months), 2 dogs were treated with thyroidectomy and chemotherapy (MST 11 months), 1 dog was treated with thyroidectomy and external beam radiation (survival time 13 months), and 6 dogs received no treatment (MST 1.5 months) (Campos et al. 2014). In dogs with surgically excised thyroid carcinoma, macroscopic and histologic evidence of vascular invasion were negative prognostic indicators (Campos et al. 2014). Ectopic sublingual thyroid carcinoma reported MST 562 days (Broome et al. 2014). Partial hyoidectomy was reported to be well tolerated in 5 dogs with ectopic thyroid carcinoma removal (Milovancev et al. 2014). Chemotherapy is considered as adjuvant treatment for non‐resectable primary or large primary carcinoma (>27 cm3), bilateral disease, or for gross metastatic disease (Leav et al. 1976; Jeglum et al. 1983; Ogilvie et al. 1991; Post and Mauldin 1992; Hammer et al. 1994; Fineman et al. 1998; Theon et al. 2000). The MST of dogs treated with surgery and chemotherapy was 518 days, which was not statistically different from that of the dogs treated with surgery alone (Nadeau and Kitchell, 2011). A clinical benefit was seen in 12/15 dogs (4 PR and 8 SD) treated with Toceranib phosphate (Palladia®) for thyroid carcinoma ( London et al. 2012 ).. Boron neutron capture therapy is investigational (Pisarev et al. 2006).
Hyperthyroid Cats
Multi‐nodular adenomatous hyperplasia (majority), malignant carcinomas (1–3%) (Lunn and Page 2013). 131I thyroid ablation is treatment of choice with reported MST 2 years (Petersen and Becker 1995), or 4 years (Milner et al. 2006), compared to 2 years for methimazole treatment (Milner et al. 2006). Treatment options are: oral anti‐thyroid medication (Peterson et al. 1988; Mooney 2001; Trepanier et al. 2003; Trepanier 2007; Frenais et al. 2009; Higgs and Hibbert 2012; Daminet et al. 2014), topical methimazole to pinna (Hoffman et al. 2002; Hoffmann et al. 2003; Sartor et al. 2004; Lecuyer et al. 2006; Hill et al. 2011, 2015a, 2015b, 2015c; Boretti et al. 2013, 2014), topical carbimazole to pinna (Buijtels et al. 2006), iodine‐restricted food (Melendez et al. 2011a, 2011b; Yu et al. 2011; van der Kooij et al. 2014; Scott‐Moncrieff et al. 2015; Hui et al. 2015), thyroidectomy (Flanders et al. 1987; Flanders 1999; Padgett 2002; Birchard 2006; Naan et al. 2006), ultrasound‐guided percutaneous ethanol injections (Wells et al. 2001; Goldstein et al. 2001), and ultrasound‐guided percutaneous radiofrequency ablation (Mallery et al. 2003). Pre‐operative scintigraphy is ideal (Lunn and Page 2013).
Table 2.2 Round cell.
Neoplasia
Researched Treatment Options and Outcomes
Mast Cell Tumor
Dogs: The mainstay of treatment is curative intent surgery with 2–3 cm margins laterally and one fascial plane deep depending on the tumor grade (Simpson et al. 2004; Fulcher et al. 2006), or a modified lateral margin approach (although 15% dirty margins were seen using this system) (Pratschke et al. 2013). High‐grade tumors at greater risk of local recurrence (Donnelly et al. 2015). Smaller margins may be adequate in lower grade tumors and width of complete margins not prognostic for local recurrence (Donnelly et al. 2015). Completeness of excision has been previously shown to be a positive prognostic indicator (Seguin et al. 2001; Weisse et al. 2002b). There was an increased risk of incompleteness of excision (when treated with wide excision with curative intent) when surgery residents performed the surgery, compared with specialist surgeons (Monteiro et al. 2011). Increased tumor size was also a significant risk factor for inadequate surgical margins (Monteiro et al. 2011). Grade I tumors may be completely excised with margins of 1 or 2‐cm laterally and one fascial plane deep (n = 4 cases), but incomplete lateral excision occurred in 2 of 19 grade II MCTs (10%) using the surgical approach of 2 cm lateral margins and one fascial plane deep (Fulcher et al. 2006). In another study, 15 of 20 cutaneous grade II MCTs were completely excised with 1 cm lateral margins and a deep margin of one fascial plane, and all were completely excised with 2 cm lateral margins and a deep margin of one fascial plane (Simpson et al. 2004). Another approach for local control is marginal surgery with adjuvant radiation, which results in 85–95% 2‐year control for stage 0, Patnaik grade I or II (al‐Sarraf et al. 1996; Frimberger et al. 1997; LaDue et al. 1998; Turrel et al. 1988). In another study, local cure was achieved in cases with incomplete margins and radiation therapy in 75–96% of dogs (al‐Sarraf et al. 1996; Frimberger et al. 1997; LaDue et al. 1998; Chaffin and Thrall 2002; Dobson et al. 2004; Hahn et al. 2004; Poirier et al. 2006). The rate of local recurrence for grade‐II MCT is reported to be as high as 50% if margin status is unknown (al‐Sarraf et al. 1996; Macy 1986). In two studies where grade II MCTs were resected with wide margins,
