Thyroid tumors Flashcards
Pessina et al. Expression of thyroid-specific transcription factors in thyroid carcinoma, contralateral thyroid lobe and healthy thyroid gland in dogs
Concentration of TSH-R, PAX-8, and ER-a mRNA were no different amound groups
Carcinom group had lower Tg abd TPO mRNA than healthy and CL group - altered capacity to synthesize thyroid hormones
TF that promoted thyrocytes proliferation, TTF-1 and IGF-1 had greater mRNA in CL group - CL lobe may function in compensatory state
Tuohy et al. 2012. Outcome following simultaneous bilateral thyorid lobectomy for treatment of thyroid gland carcinoma in dogs: 15 cases
Complications included hemorrhage and laryngeal nerve trauma
____ dogs received calcitriol
____ dogs required long term thyroid treatment
6 dogs received adjuvant chemotherapy
MST was ____ months
Successful outcome, role of chemo not clearly defined
13 dogs (87%)
8 dogs (53%)
38.3 months
Campos et al. Clinical, pathological, and immunohistochemical prognostic factors in dogs with thyroid carcinoma
70 dogs
___% had differentiated follicular cell thyroid carcinoma and ___% medullary thyroid carcinoma
Tumor diameter, tumor volume, tumor fixation, ectopic location, follicular cell origin, and ki67 were positively associated with distant metastasis
Outcome was comparable between dFTC and MTC
Macroscopic and histologic vascular invasion were independent negative predictors of disease free survival
Time to presentation, histologic vascular invasion, and Ki67 were negatively associated with time to metastases and time to presentation was negatively associated with timor to recurrence, no independent predictor were found
71%, 29%
Campos et al. Upregulation of the PI3K/Akt pathway in the tumorigenesis of canine thyroid carcinoma
The mRNA expression of VEGFR1, VEGFR2, PDPK1, AKT, and AKT2 were increased in FTC
EGFR, VEGFR-1 and PIK3CA were increased in MTC compared to normal thyroid glands
2 activating mutation in K-RAS alos noted in humans
No mutations in H-RA, N-RAS, BRAF, PTEN, RET, PIK3CA
Suggests role of PI3K/Akt pathways in pathogenesis
Campos et al. 2014. IHC expression of potential therapeutic targtes in canine thyroid carcinoma
__% of FTC and all MTC has high percentage (76-100%) of cells positive for VEGF
__% FTC and __% MTC expressed Cox2
___% of FTC and ___% MTC expressed P-gp
___ tumor was positive for p53
Expression of VEGF and pgp was higher in MTC compared to FTC
80%, all
13%, 50%
17%, 70%
No
Taeymans et al. 2013. Comparison between clinical, ultrasound, CT, MRI, and pathology findings in dogs presented for suspected thyroid carcinoma
All were larger, heterogenoeus, moderately to strongly vascularized and contained dystrophic mineralization and/or fluid accumulations
On MRI, hyperintense compared to surrounding musculature, on CT had lower attenutation than normal thyroid glands
Palpation was not accurate predictor of locally invaive vs. well-encapsulated masses
Ct had highest specificity (100%) and MRI had higher sensitivity (93%) in diagnosing thyroid CA
US is a screening tool but recommend CT or MRI for staging
Rossi et al. 2013. CT features of basihyoid ectopic thyroid carcinoma in dogs
Oval to bilobed mass centered on basihyoid bone with bone lysis, highly vascularized capsules with central poorly contrast enhancing areas
Laryngeal wall infiltrsion in all cases, 2 cases invasion of laryngeal lumen, in 1 case invasion of ventral muscular and SQ plane
Mets found in retropharyngeal LNs and in lung
Differential for mass in basihyoid regions
Mativier et al. 2014. Gene expression profiling demonstartes differential expression of osteopontin in follicular thyroid carcinomas compared to normal thyroid tissues in dogs
Osteopontin expression was increased in tumor tissue compared to normal thyroid tissue
Deitz et al. 2014. CT appearance of canine thyroid tumors
Pollard et al. 2015. Prevealence of incidental thyroid nodules in ultrasound studies of dogs with hypercalcemia
90 dogs
__% had at least 1 thyroid nodule
Thyroid cysts (33%), thyroid adenoma (33%), thyroid ACA (22%) and nodular hyperplasia (11%)
Recommend cytology if nodule is identified
15%
Pessina et al. 2016. Semiquantitative immunohistochemical marker staining and localization in canine thyroid carcinoma and normal thyroid gland
Immunoreactive proteins in follicular cells, fibroblats, and enothelial cells were assesed in thyroid CA and healthy thyroid glands
No difference in thyrotropin receptor and thyroglobulin staining but expression was higher in follicular cells than in fibroblasts
FGF-2 staining was more intense in healthy follicular cells than in carcinomas
Follicular cells had 2-3x higher TTF-1 and PCNA than healthy cells
VEGF more intense in endothelial cells of tumors than normal tissues
Ramos-Vera et al. 2016. Immunohistochemical detection of Pax-8 and Napsin A in canine thyroid tumors: comparison with thyroglobulin, calcitonin, and TTF-1
Thyroglobulin and calcitonin distinguish between follicular and C-cell origin of thyroid tumors
Pax8 (expressed by normal thyroid follicular cells) and napsin A (expressed by C-cells) was compared with labeling for TTF-1, Tg, and calcitonin
81 follicular tumors expressed Tg and negative for calcitonin; 98% expressed TTF-1 and Pax8 abbd 74% expressed napsin A
All 25 C-cell lesions expressed calcitonin and negative for Tg - 88% positive for TTF-1, 57% Pax8 and 100% napsin A
Tsimbas et al. 2018. Short survival time following palliative intent hypofractionated radiotherapy for non-resectable canine thyroid carcinoma: a retrospective analysis
95% had metastasis (7/19 LN, 16/19 distant metastasis)
5 dogs experienced local tumor response including 2 CR and 3 PR
MSt 170 days
Achivement of CR or PR was predictive of overall survival
Lorange et al. 2019. Use of a vessel-sealing device versus conventional hemostatic techniques in dogs undergoing thyroidectomy because of suspected thyroid carcinoma
Objective: To compare use of a vessel-sealing device (VSD) versus conventional hemostatic techniques in dogs undergoing thyroidectomy because of suspected thyroid carcinoma.
Design: Retrospective cohort study.
Animals: 42 client-owned dogs undergoing thyroidectomy because of suspected thyroid carcinoma.
Procedures: Medical records of dogs treated at 4 referral centers from 2010 through 2016 were reviewed, and information was obtained on patient signalment, surgical technique, tumor-specific factors, and operative duration. Postoperative hospitalization time and complications were compared between dogs grouped on the basis of hemostatic technique.
Results: Thyroidectomy was performed with a VSD in 23 dogs and with conventional hemostatic techniques (ie, ligatures, hemoclips, or electrocautery) in 19 dogs. Hemostatic technique (ie, use of a VSD vs conventional hemostatic techniques) was the only factor significantly associated with operative duration (median time, 28 vs 41 minutes). Postoperative hospitalization times and complication rates did not differ between groups.
Conclusions and clinical relevance: Results suggested that use of a VSD, rather than conventional hemostatic techniques, in dogs undergoing thyroidectomy because of suspected thyroid carcinoma resulted in shorter operative times without significantly affecting complication rates or postoperative hospitalization times.
Reagan et al. 2019. Complications and outcomes associated with unilateral thyroidectomy in dogs with naturally occurring thyroid tumors: 156 cases (2003-2015)
Objective: To describe complications and outcomes of dogs undergoing unilateral thyroidectomy for the treatment of thyroid tumors.
Animals: 156 dogs undergoing unilateral thyroidectomy for a naturally occurring thyroid tumor.
Procedures: Dogs that underwent a unilateral thyroidectomy in 2003 through 2015 were included in a multi-institutional retrospective study. For each dog, information gathered through evaluation of electronic and paper records included perioperative complications, short-term outcome (survival to discharge from the hospital vs nonsurvival), and long-term outcome (survival time).
Results: In the perioperative period, complications occurred in 31 of the 156 (19.9%) dogs; hemorrhage was the most common intraoperative complication (12 [7.7%] dogs). Five of 156 (3.2%) dogs received a blood transfusion; these 5 dogs were among the 12 dogs that had hemorrhage listed as an intraoperative complication. Immediately after surgery, the most common complication was aspiration pneumonia (5 [3.2%] dogs). One hundred fifty-three of 156 (98.1%) dogs that underwent unilateral thyroidectomy survived to discharge from the hospital. One hundred-thirteen dogs were lost to follow-up; from the available data, the median survival time was 911 days (95% confidence interval, 704 to 1,466 days).
Conclusions and clinical relevance: Results indicated that unilateral thyroidectomy in dogs with a naturally occurring thyroid tumor was associated with a perioperative mortality rate of 1.9% and a complication rate of 19.9% and that hemorrhage and aspiration pneumonia were the most common complications. Long-term survival of dogs undergoing unilateral thyroidectomy for the treatment of thyroid tumors was not uncommon.
