Alopecia, Easily Epilated Hair, & Inappetence in a Cat

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1 Consider This Case PEER REVIEWED Alopecia, Easily Epilated Hair, & Inappetence in a Cat Feline Friendly Article Jennifer C. Olson, DVM and Gary D. Norsworthy, DVM, Diplomate ABVP (Feline) Alamo Feline Health Center, San Antonio, Texas J. Scot Estep, DVM, Diplomate ACVP Texas Veterinary Pathology, San Antonio, Texas A 14-year-old spayed female domestic medium-hair cat was referred for evaluation of progressive nonpruritic dermatologic changes, inappetence, and decreased water consumption over 4 weeks; anorexia had developed in the past week. PHYSICAL EXAMINATION Upon presentation the cat had a body condition score of 4/9 and weighed 3.82 kilograms. The cat was euhydrated and, based on records from the referring veterinarian, had lost 1.32 kg during the past 12 months. No signs of excessive grooming were reported by the owner. Clinical examination findings included shiny, symmetrical alopecia on the ventral abdomen and chin, periocular alopecia and inflammation, perionychitis, and easily epilated hair (Figures 1 3). DIAGNOSTICS Laboratory Analysis Diagnostics performed the day prior to referral revealed elevated BUN, normal creatinine, mild eosinophilia, and mild hyperglycemia (Table 1). These biochemical and hematologic abnormalities were nonspecific and clinically insignificant. Figure 1. Shiny symmetrical alopecia on the ventral abdomen, with easily epilated surrounding hair. Figure 2. Perionychitis. Table 1. Pertinent laboratory results VALUE Result Reference Interval Blood urea nitrogen (mg/dl) Creatinine (mg/dl) Eosinophils ( 103/mcl) Glucose (mg/dl) View a video that demonstrates the appearance and characteristics of easily epilated hair at tvpjournal.com Figure 3. Shiny alopecia on the chin, with easily epilated surrounding hair. 12

2 Figure 4. Ultrasound image showing heterogeneous hypoechoic hepatic mass. Imaging Abdominal ultrasound identified multiple hypoechoic masses in the liver (Figure 4). The pancreas could not be identified due to gas acoustic impedance. The remainder of the ultrasound study was unremarkable. Thoracic radiographs were normal. Cytopathology Under sedation, fine-needle aspiration biopsy samples were collected from a hepatic mass using ultrasound guidance. The findings are listed in Table 2. PRESUMPTIVE DIAGNOSIS The vague acini led the pathologist to suspect biliary or pancreatic origin, but there were not enough features for definitive diagnosis. However, this information, in context of the clinical picture, led to a presumptive diagnosis of hepatobiliary adenocarcinoma and feline paraneoplastic alopecia. Based on the presumptive diagnosis and prognosis, the owners elected euthanasia. POSTMORTEM DIAGNOSTICS Gross Pathology Significant gross pathologic findings at necropsy included numerous multifocal soft pale hepatic nodules (Figures 5 through 7) while the lung, pancreas, and intra-abdominal lymph nodes appeared grossly normal. Consider This Case Figure 5. Appearance of liver when opening the abdomen during necropsy. Figure 6. Hepatic nodules in section. Alopecia, Easily Epilated Hair, & Inappetence in a Cat Table 2. Hepatic Mass Fine- Needle Aspiration Findings Multiple clumps of atypical epithelial cells with round-to-oval nuclei Marked anisokaryosis Prominent nucleoli Indistinct cell borders High nuclear to cytoplasmic ratio Vague acini, suggestive of carcinoma Figure 7. Necropsy image of the pancreas with no gross pathology. Histology Histopathology revealed glandular and solidly cellular areas that had replaced most of the pancreas and aggressive invasion of the tumor into the liver and lungs (Figures 8 10, page 14). Immunohistochemistry of the neoplastic cells was posi- January/February 2014 Today s Veterinary Practice 13

3 Consider This Case Figure 8. Histopathology of pancreatic adenocarcinoma (40 ) with near complete replacement by neoplastic cells. The neoplastic cells have a moderate amount of cytoplasm and formed vague acini. Figure 9. Histopathology of the hepatic adenocarcinoma (40 ). Figure 10. Histopathology of the lung adenocarcinoma (2 ). Figure 11. Dermatohistopathology of alopecic skin (20 ), showing follicular atrophy, parakeratosis, and neutrophilic epidermitis. tive for pancytokeratin, cytokeratin 7, cytokeratin 20, vimentin, and negative for TTF-1, synaptophysin, chromogranin, and calcitonin. These markers were designed to differentiate primary from metastatic hepatic neoplasia, and the results supported a differential of cholangiocarcinoma or pancreatic carcinoma, while ruling out thyroid, pulmonary, thymic, and neuroendocrine neoplasia. Dermatohistopathology revealed a mostly eroded Table 3. PanCreaTiC TUMor staging TUMOR: How large is the primary tumor and where is it located? TX Primary tumor cannot be evaluated T0 no histopathologic evidence of cancer found in pancreas Tis Carcinoma in situ (very early cancer that has not spread) T1 Tumor (2 cm or smaller) only in pancreas T2 Tumor (larger than 2 cm) only in pancreas T3 Tumor extends beyond pancreas; does not involve major arteries/ veins near pancreas T4 Tumor extends beyond pancreas into major arteries/veins near pancreas (not resectable) NODE: Has the tumor spread to the regional lymph nodes? NX regional lymph nodes cannot be evaluated N0 Cancer not found in regional lymph nodes N1 Cancer has spread to regional lymph nodes METASTASIS: Has the cancer metastasized to other parts of the body? MX distant metastasis cannot be evaluated M0 disease has not spread to other parts of the body M1 Cancer has spread to another part of the body, including distant lymph nodes. stratum corneum, with some focal areas of parakeratosis, moderate to severe acanthosis, and telogenized hair follicles, which were diffusely miniaturized (Figure 11). Sebaceous glands were unaffected and appeared enlarged. According to the World Health Organization tumor staging for pancreatic tumors in domestic animals, 1 this patient was classified as T1 N0 M1 (Table 3). DISCUSSION The pathophysiology of feline paraneoplastic alopecia is unknown. It is one of very few cutaneous paraneoplastic syndromes identified in veterinary medicine and is linked to pancreatic and biliary carcinoma. 2-5 The first case series of 3 cats with this syndrome was published in A case report demonstrated that excision of the primary tumor was followed by resolution of dermatologic lesions, and subsequent metastatic disease mirrored a recurrence of dermatologic lesions. 6 This particular case report demonstrated that, while pancreatic disease may be present and is likely the location of the primary tumor, metastatic hepatic lesions may be the most easily identifiable pathology antemortem. Therefore, it is important to determine if pancreatic pathology is also present. 14

4 The Dermatology Component: Differential Diagnoses differential diagnoses for the alopecia are listed in Table 4. 7,8 rule outs were based upon: no evidence of skin fragility on physical examination, as reported in cats with hyperadrenocorticism 9 no ectoparasites identified on examination in this case, skin scraping, skin cytology, trichogram, and fungal cultures were not performed as the imaging and fine-needle aspiration biopsy results indicated a neoplastic process. no perifollicular inflammation or mites/ fungal spores were seen in biopsy samples normal total T 4 level 3 weeks prior to referral (1.8 mcg/dl; reference interval, 0.8 4). Telogen effluvium was possible as a consequence of internal or systemic disease as a synchronous trigger for the onset of telogen phase. 8 however, the characteristic clinical appearance, absence of findings consistent with other disorders, and dermatohistopathology findings made paraneoplastic alopecia the most likely diagnosis in this case. Table 4. differential diagnoses for nonpruritic symmetrical alopecia alopecia areata demodicosis dermatophytosis hyperadrenocorticism hyperthyroidism Paraneoplastic alopecia self-induced alopecia secondary to allergies or ectoparasitism Telogen effluvium Clinical Signs Classic physical examination findings include shiny, nonpruritic symmetrical alopecia affecting the ventral body, face, and medial aspect of limbs, with easily epilated hair. 6,10,11 Less commonly, pinnal and periocular alopecia can occur. Abnormally soft footpads, 6 dry footpad fissures, 11 crusted footpads, 12 and lightening of hair color 10 have been reported as well. Pruritus has been linked to secondary Malassezia species infection in one report. 6 The most common sign of systemic illness is weight loss. 3 Relation of Alopecia to Tumor Feline paraneoplastic alopecia is characterized histopathologically by loss of the stratum corneum and severe follicular atrophy, with miniaturized hair bulbs. 6,10,11 The shiny Consider This Case Key Point: Application in Practice The unique dermatologic signs associated with feline paraneoplastic alopecia shiny, nonpruritic alopecia and easily epilated hair should be a sentinel for possible intra-abdominal malignancy. recognition of these signs may facilitate detection of pancreatic adenocarcinoma. to glistening appearance of the skin is attributed to exfoliation of the stratum corneum, 11 which may occur during normal or excessive grooming. It is theorized that humoral factors are excreted or triggered by the tumor, but specific factors have not been identified. By definition, though, the dermatologic lesions are themselves noncancerous; they are, instead, neoplasm-related lesions that occur at a site distant from the primary tumor or its metastasis. 3 Therapy & Prognosis Cats with pancreatic adenocarcinoma have a grave prognosis, and most have metastatic disease at the time of diagnosis. 12 To the best of our knowledge, there are currently no effective treatments. SUMMARY Feline pancreatic adenocarcinoma is a rare condition; however, the uniqueness of dermatologic changes should be a sentinel for possible intra-abdominal neoplasia, typically pancreatic, and a trigger to pursue abdominal ultrasound and biopsy. To view the references for this article, go to todays veterinarypractice.com/resources.asp#resources. Jennifer C. Olson, DVM, practices at Alamo Feline Health Center in San Antonio, Texas. She received her DVM from Cornell University and completed an internship at VCA Alameda East Veterinary Hospital in Denver, Co. Gary D. Norsworthy, DVM, Diplomate ABVP (Feline), is the owner of Alamo Feline Health Center in San Antonio, Texas, one of the largest feline practices in the United States. He is a frequent lecturer and the editor of the textbook, The Feline Patient. He received his DVM from Texas A&M University. J. Scot Estep, DVM, Diplomate ACVP, is the owner of Texas Veterinary Pathology in San Antonio, Texas. He received his DVM from Oklahoma State University and completed a residency in pathology at the Armed Forces Institute of Pathology. alopecia, easily epilated hair, & inappetence in a CaT January/February 2014 Today s Veterinary Practice 15

5 Consider This Case References 1. Owen LN. TNM classification of tumors in domestic animals. Geneva: World Health Organization, Brooks DG, Campbell KL, Dennis JS, et al. Pancreatic paraneoplastic alopecia in three cats. JAAHA 1994; 30: Turek, MM. Cutaneous paraneoplastic syndromes in dogs and cats: a review of the literature. Vet Derm 2003; 14: Marconato L, Albanese F, Viacava P, et al. Paraneoplastic alopecia associated with hepatocellular carcinoma in a cat. Vet Derm 2007; 18: Van der Luer R, Van den Ingh T, Van Hoe N, et al. Feline paraneoplastic alopecia. Tijdschr Diergeneeskd 2008; 18(4): Godfrey DR. A case of feline paraneoplastic alopecia with secondary Malassezia-associated dermatitis. J Small Anim Pract 1998; 39: Scott DW, Miller WH, Griffin CE. Endocrine and metabolic diseases. In Scott DW (ed): Muller and Kirk s Small Animal Dermatology, 5th ed. Philadelphia: WB Saunders, 1995, pp Thoday KL. Diagnosis and management of symmetrical alopecia. In August JR (ed): Consultations in Feline Internal Medicine. 3rd ed. Philadelphia: WB Saunders, 1997, pp Helton-Rhodes K, Wallace M, Baer K. Cutaneous manifestation of feline hyperadrenocorticism. In Ihrke PJ, Mason IS, White SD (eds): Advances in Veterinary Dermatology, Volume 2. Oxford: Pergamon Press, 1993, pp Tasker S, Griffon DJ, Nuttall TJ, et al. Resolution of paraneoplastic alopecia following surgical removal of a pancreatic adenocarcinoma in a cat. J Small Anim Pract 1999; 40: Pascal-Tenorio A, Olivry T, Gross TL, et al. Paraneoplastic alopecia associated with internal malignancies in the cat. Vet Derm 1997; 8: Seaman RL. Exocrine pancreatic neoplasia in the cat: A case series. JAAHA 2004; 40: Suggested Reading Barrs VR, Martin P, France M, et al. What is your diagnosis? J Small Anim Pract 1999; 40:559. Heripret D. Dermatological manifestations of systemic disease. In Guaguere E (ed): A Practical Guide to Feline Dermatology. Oxford: Blackwell Science, 2000, pp McLean DI, Haynes HA. Cutaneous manifestations of internal malignant disease: Cutaneous paraneoplastic syndromes. In Freedberg IM (ed): Fitzpatrick s Dermatology in General Medicine, 6th ed. New York: McGraw-Hill, 2003, pp