-
Journal of the American Veterinary... Oct 2023To evaluate short- and long-term outcomes for dogs undergoing anal sacculectomy for massive (> 5 cm) apocrine gland anal sac adenocarcinoma (AGASACA).
OBJECTIVE
To evaluate short- and long-term outcomes for dogs undergoing anal sacculectomy for massive (> 5 cm) apocrine gland anal sac adenocarcinoma (AGASACA).
ANIMALS
28 client-owned dogs with massive AGASACA.
PROCEDURES
A retrospective multi-institutional study was performed. Pre-, intra-, and post-operative data was collected, and variables were statistically analyzed for associations with progression-free interval (PFI) and overall survival (OS).
RESULTS
At the time of anal sacculectomy, 19 (68%) dogs underwent concurrent iliosacral lymph node extirpation, including 17 of 18 (94%) dogs with suspected nodal metastasis preoperatively. Five (18%) dogs experienced grade 2 intraoperative complications. Ten (36%) dogs experienced postoperative complications, including 1 grade 3 and 1 grade 4 complication. No dogs had permanent fecal incontinence, tenesmus, or anal stenosis. Nineteen dogs received adjuvant chemotherapy, radiation, or both. Local recurrence occurred in 37% of dogs. Dogs with lymph node metastasis at surgery were more likely than dogs without metastasis to develop new/progressive lymph node metastasis (10/17 [59%] vs 0/10 [0%]; P = .003) and distant metastasis (7/17 [41%] vs 0/10 [0%]; P = .026). Median PFI was 204 days (95% CI, 145 to 392). Median OS was 671 days (95% CI, 225 to upper limit not reached). Nodal metastasis at the time of surgery was associated with shorter PFI (P = .017) but not OS (P = .26). Adjuvant therapy was not associated with outcome.
CLINICAL RELEVANCE
Dogs with massive AGASACA experienced prolonged survival following anal sacculectomy despite a high incidence of local recurrence and metastasis. Lymph node metastasis at the time of surgery was a negative prognostic indicator for PFI but not OS.
Topics: Animals; Dogs; Adenocarcinoma; Anal Gland Neoplasms; Anal Sacs; Apocrine Glands; Dog Diseases; Lymphatic Metastasis; Retrospective Studies
PubMed: 37225157
DOI: 10.2460/javma.23.02.0102 -
Scientific Reports Jul 2023Naturally occurring canine cancers have remarkable similarities to their human counterparts. To better understand these similarities, we investigated 671 client-owned... (Comparative Study)
Comparative Study
Naturally occurring canine cancers have remarkable similarities to their human counterparts. To better understand these similarities, we investigated 671 client-owned dogs from 96 breeds with 23 common tumor types, including those whose mutation profile are unknown (anal sac carcinoma and neuroendocrine carcinoma) or understudied (thyroid carcinoma, soft tissue sarcoma and hepatocellular carcinoma). We discovered mutations in 50 well-established oncogenes and tumor suppressors, and compared them to those reported in human cancers. As in human cancer, TP53 is the most commonly mutated gene, detected in 22.5% of canine tumors overall. Canine tumors share mutational hotspots with human tumors in oncogenes including PIK3CA, KRAS, NRAS, BRAF, KIT and EGFR. Hotspot mutations with significant association to tumor type include NRAS G61R and PIK3CA H1047R in hemangiosarcoma, ERBB2 V659E in pulmonary carcinoma, and BRAF V588E (equivalent of V600E in humans) in urothelial carcinoma. Our findings better position canines as a translational model of human cancer to investigate a wide spectrum of targeted therapies.
Topics: Animals; Dogs; Oncogene Proteins; Mutation; Neoplasms; Humans; Antineoplastic Agents
PubMed: 37414794
DOI: 10.1038/s41598-023-37505-2 -
The Journal of Small Animal Practice Jun 2024To report the histopathological diagnosis of both anal sacs in dogs undergoing bilateral anal sacculectomy for the treatment of unilateral apocrine gland anal sac...
Histopathological diagnosis and surgical complications following bilateral anal sacculectomy for the treatment of unilateral canine apocrine gland anal sac adenocarcinoma: 35 cases (2019-2023).
OBJECTIVES
To report the histopathological diagnosis of both anal sacs in dogs undergoing bilateral anal sacculectomy for the treatment of unilateral apocrine gland anal sac adenocarcinoma and to compare the surgical complication rate associated with this procedure in this population with previously published literature.
MATERIALS AND METHODS
Records were retrospectively reviewed for dogs that underwent bilateral anal sacculectomy for the treatment of apparently unilateral apocrine gland anal sac adenocarcinoma, at a single institute between 2019 and 2023. Clinical staging, surgical treatment, histological findings, intra- and postoperative complications were evaluated.
RESULTS
Thirty-five dogs were included. Only five of 35 (14%) dogs were found to have histologically normal contralateral anal sacs. Non-neoplastic anal sac disease was found in 23 of 35 (66%) dogs and bilateral apocrine gland anal sac adenocarcinoma was seen in seven of 35 (20%) dogs. None of the dogs diagnosed with bilateral neoplasia had evidence of bilateral neoplasia before surgery despite a thorough work-up. Complications attributable to the primary tumour removal were seen in 9% of dogs intraoperatively and 14% of dogs postoperatively, commonly tumour capsule disruption and surgical site infection, respectively.
CLINICAL SIGNIFICANCE
Bilateral anal sac disease was diagnosed histologically in the majority of presumed normal anal sacs, with 20% of cases being found to have bilateral apocrine gland anal sac adenocarcinoma. The surgical complication rates of this cohort were comparable to those reported for unilateral anal sacculectomy alone. These findings promote and encourage the use of bilateral anal sacculectomy in cases of suspected unilateral anal sac neoplasia.
Topics: Dogs; Animals; Dog Diseases; Anal Sacs; Adenocarcinoma; Retrospective Studies; Male; Female; Postoperative Complications; Anal Gland Neoplasms; Apocrine Glands
PubMed: 38594872
DOI: 10.1111/jsap.13731 -
International Journal of Molecular... Jun 2024Apocrine gland anal sac adenocarcinoma is an aggressive neoplasm, and surgery remains the treatment of choice, although it is controversial in advanced cases. The...
Apocrine gland anal sac adenocarcinoma is an aggressive neoplasm, and surgery remains the treatment of choice, although it is controversial in advanced cases. The prognostic factors are not well established. Human Epidermal Growth Factor Receptor 2 (HER2) is a membrane protein related to tumorigenesis, whereas Ki67 is a nuclear protein related to cell proliferation. Both are potential prognostic markers and therapeutic targets. This study aimed to evaluate the expression of HER2 and Ki67 markers in canine apocrine gland anal sac adenocarcinoma. The tumor samples were divided into four groups: largest tumor diameter less than 2.5 cm, largest tumor diameter greater than 2.5 cm, metastatic lymph nodes, and control group of non-neoplastic anal sacs. Each contained 10 samples. Immunohistochemistry was performed to verify the expression of HER2 and Ki67 markers. Positive HER2 staining was observed in 45% of the neoplastic cases and negative HER2 staining in 100% of the control group. The Ki67 expression had a median of 25% in all groups, except for the control group, which had a median of 8%. The HER2 and Ki67 expression was present in apocrine gland anal sac adenocarcinoma, making them potential therapeutic targets. However, it was not possible to determine the clinical value of either marker.
Topics: Ki-67 Antigen; Adenocarcinoma; Receptor, ErbB-2; Apocrine Glands; Immunohistochemistry; Humans; Biomarkers, Tumor; Animals; Anal Sacs; Dogs; Female; Male; Anal Gland Neoplasms
PubMed: 38928157
DOI: 10.3390/ijms25126451 -
Journal of the American Veterinary... Nov 2023To report the short-term and long-term outcomes of dogs that underwent the modified closed and traditional closed anal sacculectomy procedures for the treatment of anal...
OBJECTIVE
To report the short-term and long-term outcomes of dogs that underwent the modified closed and traditional closed anal sacculectomy procedures for the treatment of anal sac neoplasia.
ANIMALS
90 client-owned dogs.
METHODS
The medical records of 2 tertiary referral hospitals were reviewed to identify dogs that underwent anal sacculectomy for treatment of anal sac neoplasia between January 2016 and December 2020. Data collected included signalment and preoperative diagnostic findings. The occurrence of intraoperative and postoperative complications, short-term outcomes, and long-term outcomes were also collected. Descriptive statistics were calculated to summarize dog signalment information, and recurrence, metastasis, and survival proportions were compared between techniques using Fisher exact tests.
RESULTS
35 and 55 dogs, respectively, underwent the modified or traditional closed anal sacculectomy procedure. Minor postoperative complications that resolved with minimal intervention occurred in 5 of 35 (14.3%) modified approach dogs and 12 of 55 (21.8%) traditional approach dogs. Tumor recurrence was confirmed in 8 of 35 (22.9%) modified and 8 of 55 (26.4%) traditional approach dogs and was suspected in 3 of 35 (8.6%) and 6 of 55 (13.2%; P = .68), respectively. Confirmed metastatic disease was identified in 8 of 35 (22.9%) and 14 of 53 (26.4%) modified and traditional approach dogs, respectively, and was suspected in 4 of 35 (11.4%) and 7 of 53 (13.2%). Sixty-three (70%) dogs survived to study conclusion.
CLINICAL RELEVANCE
No benefits in complication rate or local recurrence were identified in dogs following the modified approach as opposed to the traditional closed anal sacculectomy technique.
Topics: Humans; Dogs; Animals; Anal Sacs; Neoplasm Recurrence, Local; Anus Neoplasms; Medical Records; Postoperative Complications; Dog Diseases; Retrospective Studies
PubMed: 37586695
DOI: 10.2460/javma.23.05.0239 -
The Canadian Veterinary Journal = La... Sep 2023An 11-year-old castrated mixed-breed dog was diagnosed with a unilateral anal sac mass. Anal sacculectomy was performed without complication. Histopathology of the mass...
An 11-year-old castrated mixed-breed dog was diagnosed with a unilateral anal sac mass. Anal sacculectomy was performed without complication. Histopathology of the mass was consistent with a well-differentiated mast cell tumor. Analyses for the Ki-67 protein, KIT expression pattern, and the presence of mutations were done. Recovery from surgery was unremarkable and repeat staging revealed no evidence of mast cell disease at 4, 8, and 12 mo after surgery. To the authors' knowledge, primary mast cell neoplasia of the anal sac has not previously been reported in the veterinary literature. Key clinical message: Although mast cell tumors of the perineal region are commonly encountered in veterinary practice, the anal sac represents a novel location for this disease. Cytology of anal sac masses can be a useful diagnostic tool to confirm the diagnosis, guide staging, and assist in treatment decisions.
Topics: Dogs; Animals; Anal Sacs; Mast Cells; Perineum; Neoplasms; Dog Diseases
PubMed: 37663027
DOI: No ID Found -
Animals : An Open Access Journal From... Jun 2024Ultrasonographic evaluation of canine and feline anal sacs is a practical promising modality to identify anal sac disease. However, limited data are available about...
Ultrasonographic evaluation of canine and feline anal sacs is a practical promising modality to identify anal sac disease. However, limited data are available about normal ultrasound morphology of the anal sacs. This study describes the ultrasound morphology of presumed normal anal sacs in a larger sample of client-owned dogs and cats. A single-institutional prospective cross-sectional descriptive study was performed, and 137 dogs and 131 cats were included. The most common ultrasound features of the evaluated anal sacs in the dorsal plane were oval shape (99.3% of dogs and 98.5% of cats) and bilaterally similar content (94.2% of dogs and 95.4% of cats), mostly hypoechoic with diffusely hyperechoic points or unformed echogenic material (42.6% of dogs and 44% of cats). Gas in the lumen of the anal sac was detected in two dogs and mineralization in one dog. There was a statistically significant positive correlation between body weight and the size of anal sacs in dogs ≤15 kg and cats and a correlation between age and the size of anal sacs in cats. This simple method provides additional clinically significant information in detecting abnormal findings in asymptomatic patients and could contribute to the early detection of anal sac disease.
PubMed: 38891731
DOI: 10.3390/ani14111684 -
Animals : An Open Access Journal From... Apr 2024Cancer is the leading cause of death in companion animals. The evaluation of locoregional lymph nodes, known as lymph node mapping, is a critical process in assessing... (Review)
Review
Cancer is the leading cause of death in companion animals. The evaluation of locoregional lymph nodes, known as lymph node mapping, is a critical process in assessing the stage of various solid tumors, such as mast cell tumors (MCTs), anal gland anal sac adenocarcinoma, melanoma, and mammary gland adenocarcinoma. MCTs are among the most prevalent skin malignancies in dogs. Staging is used to describe the extent of neoplastic disease, provide a framework for rational treatment planning, and evaluate treatment results. The aim of this review is to present the current knowledge on sentinel lymph node (SLN) mapping in canine MCTs, its influence on treatment decisions and prognosis, as well as the advantages and limitations of different SLN techniques currently available in veterinary oncology. A search methodology was adopted using the PubMed, Scopus, and Google Scholar databases. Critical analyses of up-to-date research have shown that lymphoscintigraphy can achieve a lymph node detection rate of between 91 and 100%. This method is becoming increasingly recognized as the gold standard in both human and veterinary medicine. In addition, initial studies on a limited number of animals have shown that computed tomographic lymphography (CTL) is highly effective in the SLN mapping of MCTs, with detection rates between 90 and 100%. The first study on contrast-enhanced ultrasound (CEUS) also revealed that this advanced technique has up to a 95% detection rate in canine MCTs. These methods provide non-ionizing alternatives with high detection capabilities. Furthermore, combining computed tomography and near-infrared fluorescence (NIR/NIR-LND) lymphography is promising as each technique identifies different SLNs. Indirect lymphography with Lipiodol or Iohexol is technically feasible and may be also used to effectively detect SLNs. The integration of these mapping techniques into routine MCT staging is essential for enhancing the precision of MCT staging and potentially improving therapeutic outcomes. However, further clinical trials involving a larger number of animals are necessary to refine these procedures and fully evaluate the clinical benefits of each technique.
PubMed: 38612328
DOI: 10.3390/ani14071089 -
Veterinary Surgery : VS Mar 2024To evaluate the postoperative complication rate and local recurrence rate of apocrine gland anal sac adenocarcinoma (AGASACA) in dogs surgically treated with a modified...
OBJECTIVE
To evaluate the postoperative complication rate and local recurrence rate of apocrine gland anal sac adenocarcinoma (AGASACA) in dogs surgically treated with a modified closed anal sacculectomy technique between 2015 and 2022.
STUDY DESIGN
Observational clinical retrospective study.
ANIMAL POPULATION
Forty-seven client-owned dogs histologically diagnosed with AGASACA.
METHODS
Medical records were evaluated for patient demographics and history, physical examination findings, diagnostic imaging, incidence of concurrent neoplasia, postoperative complications, and incidence and time to local recurrence. Dogs with at least 150 days of follow-up were included in evaluation of local recurrence.
RESULTS
Two dogs were euthanized at 4 and 11 days after surgery. Forty-five dogs were included for long-term local recurrence evaluation, with a median of 364 days of follow-up (range 156-2156 days). Only one dog (2.2%) developed local recurrence with a time to recurrence of 90 days. Postoperative complications were reported in 15 dogs (31.9%) and were considered minor in 14 dogs (93.3%) and major in one dog (6.7%). Mean survival time for the 20 dogs that were deceased as of November 1, 2022 was 521 days (range 156-1409 days) and the median survival time was 388 days.
CONCLUSION
The modified closed anal sacculectomy technique resulted in a lower AGASACA local recurrence rate than previously reported in the veterinary literature with a comparable postoperative complication rate.
CLINICAL SIGNIFICANCE
Given the low recurrence rate found in this study, the modified closed anal sacculectomy technique may reduce the need for adjuvant radiation therapy and potentially chemotherapy in AGASACA patients.
PubMed: 38477012
DOI: 10.1111/vsu.14084 -
Veterinary Sciences May 2024This research aims to evaluate the outcomes of a radiotherapy protocol, consisting of five fractions of 4 Gy each, resulting in a total dose of 20 Gy for apocrine gland...
Radiotherapy for Canine Apocrine Gland Anal Sac Adenocarcinoma: Survival Outcomes and Side Effects of a Palliative Treatment Protocol of 20 Gy in Five Consecutive Fractions.
This research aims to evaluate the outcomes of a radiotherapy protocol, consisting of five fractions of 4 Gy each, resulting in a total dose of 20 Gy for apocrine gland anal sac tumors and local lymph nodes in canines. This protocol was assessed as a palliative treatment for macroscopic tumors alone, or in combination with additional therapies under different scenarios. Medical records from fifty canine patients met the inclusion criteria and were divided into different treatment groups: radiotherapy alone (n = 22, 44%), radiotherapy with chemotherapy or targeted therapy with toceranib (n = 18, 36%), surgery with radiotherapy (n = 5, 10%), and surgery with radiotherapy and chemotherapy or targeted therapy with toceranib (n = 5, 10%). Patients who received radiotherapy alone had a median survival time of 384 days (95% CI 198-569) and 628 days (95% CI 579-676) for RT + additional therapies. The median time to progression for patients with radiotherapy alone was 337 days (95% CI 282-391 days), and 402 days (95% CI 286-517 days) for radiotherapy plus additional treatments. Acute side effects were mild, with the majority having diarrhea (61%), and only one patient developed grade III late effects VRTOG v2 classification; however, this happened 22 months after the first radiotherapy protocol after re-irradiation. The results demonstrate that radiotherapy alone under this protocol provided a comparable median time to progression vs. radiotherapy plus additional treatments while maintaining acceptable side effects. The combination of this protocol with other treatment modalities offers attractive results for local disease control and survival while maintaining acceptable toxicities. Overall, these findings contribute to the growing evidence supporting the role of radiotherapy in managing apocrine gland anal sac adenocarcinoma in dogs.
PubMed: 38787191
DOI: 10.3390/vetsci11050219