DERMATOLOGY
Basal Cell Carcinomas Basal cell tumours are a benign tumour that look very similar to SCC , and are quite common in cats in other parts of the world . In dogs , they typically occur around the head and are not unlike canine cutaneous histiocytoma ( hence the need
Figure 5 . Multiple raised SCC on the ventrum of a dog ; the previous surgeries have contributed to scar tissue formation , which makes radiation less effective , and future surgeries more difficult . The widespread nature of the disease means a novel approach must be taken if control is to be achieved . Patients arriving at this stage are major challenges to cure . for a tissue diagnosis ). They are usually single , raised , ulcerated “ button-like ” tumours . Surgery alone is normally curative . They can be diagnosed by cytology or histopathology . BCC and SCC are classed together as the “ Keratinocytic Skin Cancers ”.
References
BERGMAN , P . J . 2007 . Anticancer vaccines . Vet Clin North Am Small Anim Pract , 37 , 1111-9 ; vi-ii . BROCKLEY , L . K ., COOPER , M . A . & BENNETT , P . F . 2013 . Malignant melanoma in 63 dogs ( 2001-2011 ): the effect of carboplatin chemotherapy on survival . N Z Vet J , 61 , 25-31 . DANK , G ., RASSNICK , K . M ., SOKOLOVSKY , Y ., GARRETT , L . D ., POST , G . S ., KITCHELL , B . E ., SELLON , R . K ., KLEITER , M ., NORTHRUP , N . & SEGEV , G . 2012 . Use of adjuvant carboplatin for treatment of dogs with oral malignant melanoma following surgical excision . Vet Comp Oncol , 9999 . EMANUEL , E . J . & JOFFE , S . 2003 . Ethics in Oncology . In : HOLLAND , M . & FREI , E . ( eds .) Cancer Medicine 6 . 6th ed .: Lippincott . GILL , V . L ., BERGMAN , P . J ., BAER , K . E ., CRAFT , D . & LEUNG , C . 2008 . Use of imiquimod 5 % cream ( Aldara ) in cats with multicentric squamous cell carcinoma in situ : 12 cases ( 2002-2005 ). Vet Comp Oncol , 6 , 55-64 . GROSENBAUGH , D . A ., LEARD , A . T ., BERGMAN , P . J ., KLEIN , M . K ., MELEO , K ., SUSANECK , S ., HESS ., P . R ., JANKOWSKI , M . H ., KURZMAN , I . & WOLCHOK , J . D . 2011 . Safety and efficacy of a xenogeneic DNA vaccine encoding for human tyrosinase as adjunctive treatment for oral malignant melanoma in dogs following surgical excision of the primary tumor . American Journal of Veterinary Research , 72 , 1631-1638 . KILLICK , D . R ., STELL , A . J . & CATCHPOLE , B . 2015 . Immunotherapy for canine cancer--is it time to go back to the future ? J Small Anim Pract , 56 , 229-41 . MARTIN , P . D . & ARGYLE , D . J . 2013 . Advances in the management of skin cancer . Veterinary Dermatology , 24 , 173-e38 . MCLEAN , J . L . & LOBETTI , R . G . 2015 . Use of the melanoma vaccine in 38 dogs : The South African experience . J S Afr Vet Assoc , 86 , 1246 . OTTNOD , J . M ., SMEDLEY , R . C ., WALSHAW , R ., HAUPTMAN , J . G ., KIUPEL , M . & OBRADOVICH , J . E . 2013 . A retrospective analysis of the efficacy of Oncept vaccine for the adjunct treatment of canine oral malignant melanoma . Vet Comp Oncol , 11 , 219-29 . PETERS-KENNEDY , J ., SCOTT , D . W . & MILLER , W . H ., JR . 2008 . Apparent clinical resolution of pinnal actinic keratoses and squamous cell carcinoma in a cat using topical imiquimod 5 % cream . J Feline Med Surg , 10 , 593-9 .
Photos : Courtesey Inanda Vet ( Dr Anthony Zambeli )
SURGICAL TIPS
FOR PERFORMING NASAL PLANUM RESECTION FOR SQUAMOUS CELL CARCINOMA
Dr RC Elliott BVSc MMedVet Surgery ( Bryanston Veterinary Hospital )
Introduction Nasal planum resection or planectomy is a drastic surgical procedure in the treatment of malignant disease of the nasal cartilage . It involves circumferential resection of the nasal cartilage rostral to the nasal and incisive bone of the maxilla .
Even though this is considered drastic surgery mainly due to the appearance of the patient post operatively it gives the best chance of resolution in the case of highly invasive squamous cell carcinoma ( SCC ).
1
Tip 1 . Always discuss the postoperative appearance of the patient after the surgery with the client prior to the surgery . Often people don ’ t understand that the entire nasal cartilage will be removed and I find it best to show a picture of the post-operative appearance prior to surgery .
Cryotherapy and radiation are the other most common modalities that can be used for treatment of invasive SCC . The reality is these do not provide gzood clean surgical margins , are generally multiple treatments over a period of time . They can delay the presentation of a patient for surgery but may adversely affect the long-term prognosis for survival . They can be given as alternative options to clients adverse to nasal planum resection .
2
Tip 2 . Surgery provides the best modality for a clinical cure . However it is considered invasive . Ideally surgery should not be delayed until the SCC has destroyed the entire nasal cartilage .
Surgical procedure Complete staging is imperative prior to performing such an invasive surgical procedure . This entails biopsy and culture of the lesion , thoracic radiographs , lymph node aspirates
GRADE Tis
T1a T1b T2 T3 T4
DESCRIPTION
Carcinoma in situ ( superficial ulcerative / crusting lesion not extending through the basement membrane )
Larger lesion < 1.5 cm , exophytic Larger lesion > 1.5 cm , superficial or minimally invasive Ulcerative or infiltrative lesion ≥2cm Larger lesion 2-5 cm or with invasion of subcutis Invading muscle , bone or fascia
Table 1 : Staging of SCC in felines courtesy of the WHO ( Reference 1 )
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