DermaVet Journal Club: September 2026

Summary. The September 2026 review focuses mainly on canine atopic dermatitis, feline parasitic diseases, skin infections and mast cell tumors. The revised ICADA guidelines divide the treatment of atopic dermatitis into two phases: a reactive phase, in which glucocorticoids are recommended for their speed of action, followed by a proactive phase that maintains remission. A placebo-controlled trial shows that atinvicitinib, a Janus kinase inhibitor, is effective once daily, without an induction phase. For oclacitinib, shortening the induction from fourteen to six days did not significantly change the outcome. In cats, a pilot study reports that a single topical application of esafoxolaner, eprinomectin and praziquantel eliminated Lynxacarus radovskyi. Selamectin combined with sarolaner, for its part, eliminates Notoedres cati within 30 days. When facing a skin infection, the causative agent should be identified to species level before treatment, because polymicrobial infection recurs more often and its isolates tend to resist more antibiotics. Methicillin-resistant staphylococci also circulate durably between a dog and its family. This identification matters all the more because feline histoplasmosis and protothecosis are now described outside their usual areas, and autochthonous cases of canine pythiosis are reported in Italy. Finally, density on three-phase computed tomography helps distinguish small mast cell tumors from benign lesions.

The September 2026 review brings together 35 articles devoted to canine and feline skin, or touching on their dermatology through microbiology, parasitology, oncology and endocrinology. Canine atopic dermatitis dominates the month: ICADA publishes revised treatment guidelines, and two trials refine the use of Janus kinase inhibitors. Infections form the second group, with resistant staphylococci passing from dogs to humans and rare agents identified by molecular methods, sometimes far from their usual areas. Oncology contributes diagnostic and prognostic tools for mast cell tumors. In cats, two antiparasitic combinations are evaluated. The articles are sorted into seven categories. Each one is presented with its design, its results and what it changes in practice.

1 Canine atopic dermatitis

1.1 Guidelines and practice

The International Committee on Allergic Diseases of Animals (ICADA) has revised its treatment guidelines for canine atopic dermatitis. They now classify treatment by mode of action and divide it into two phases: a reactive phase, which clears existing pruritus and lesions, followed by a proactive phase, which maintains remission and spaces out flares. They rely on randomized trials and systematic reviews, where available. The level of evidence is graded according to the SORT scale (Strength of Recommendation Taxonomy). For the reactive phase, fast-acting broad-spectrum drugs are recommended, particularly glucocorticoids. Janus kinase inhibitors and lokivetmab can be effective depending on lesion type, severity and the complexity of the inflammation. Secondary infections and flare factors must be managed. For the proactive phase, the choice depends on the disease profile and the dog’s response. Options include skin barrier care, infection control, allergen avoidance, allergen immunotherapy, topical glucocorticoids, ciclosporin, tacrolimus, lokivetmab or Janus kinase inhibitors. None of these interventions is required in every dog, none is interchangeable with another and none is effective in every case. The choice therefore takes into account efficacy, safety, convenience, cost, the quality of life of the dog and the owner, and the regulations of the country (Mueller et al., 2026).

An online survey of North American veterinarians was conducted from July 15 to August 15, 2025. Of 718 eligible respondents, 57% estimated that at least a quarter of their clients had significant financial constraints, and 28% that at least half did. Most respondents always or often used the client’s financial situation to guide their recommendations. Skin cytology, followed by skin scraping, were rated the most important tests, regardless of financial constraint. When the budget was tight, cephalexin was preferred for methicillin-susceptible pyoderma. Most respondents were aware of the recommendation of topical antiseptic therapy alone for methicillin-resistant superficial pyoderma. A majority also recommended aerobic bacterial culture before any antibiotic when resistance was suspected. Financial constraints therefore do not always change recommendations, but these recommendations sometimes depart from consensus guidelines. The answers remain self-reported, collected through direct questions or fictional cases (Gentry et al., 2026).

1.2 Janus kinase inhibitors

Atinvicitinib is a second-generation JAK1 inhibitor, highly selective in dogs. Its efficacy was evaluated in a multicenter, randomized, blinded, placebo-controlled trial in 61 client-owned dogs with atopic dermatitis, at least 12 months old and weighing at least 2 kg. With their meal, 21 dogs received 0.8 to 1.2 mg/kg once daily for 28 days. Another 21 received 0.4 to 0.6 mg/kg twice daily for 14 days, then once daily for 14 days. The remaining 19 received a placebo. Success was defined as a reduction of at least 50% in the pruritus score or the CADESI-04 lesion score on Day 28. It was achieved in 87.5% of dogs treated once daily and in 73.3% of dogs on the two-step regimen, versus 23.1% on placebo. Both differences were significant. Pruritus decreased significantly more than with placebo in both treated groups. The lesion score decreased significantly more than with placebo in the once-daily group. Mean laboratory values remained within reference intervals and treatment was well tolerated. The authors therefore conclude that a single daily dose is safe and effective (Jirjis et al., 2026).

With oclacitinib, switching to once-daily dosing after induction sometimes brings pruritus back. A team in Munich therefore compared two regimens in 45 dogs with atopic dermatitis, randomized into two groups. The standard regimen gave 0.4 to 0.6 mg/kg twice daily for 14 days, then once daily for 7 days. The shortened induction gave the drug twice daily for 6 days, then once daily for 15 days. Data from 40 dogs could be analyzed. With the standard regimen, the mean CADLI lesion score went from 13.4 to 8, a nonsignificant decrease. With the shortened induction, it went from 12.9 to 6.9, and this decrease was significant. Mean pruritus decreased significantly in both groups, from 6.4 to 2.1 with the standard regimen and from 5.7 to 1.9 with the shortened induction. No difference appeared between groups. The rebound of pruritus after the dose reduction affected only two dogs on the standard regimen and one dog on the shortened induction (Popp et al., 2026).

1.3 Systemic inflammation and fatty acids

In humans, moderate to severe atopic dermatitis is increasingly regarded as a systemic inflammatory disease. To test this in dogs, six serum cytokines were measured: TNF-α, TNF-β or lymphotoxin-α, IL-1β, IL-6, IL-12 and IL-1 receptor antagonist. The 40 client-owned dogs were divided into four groups of 10: healthy dogs, mild atopic dermatitis, moderate to severe atopic dermatitis, and active pemphigus foliaceus as a positive control. Variability between individuals was high, and none of the six cytokines differed significantly between groups. This result may reflect a true absence of systemic inflammation in atopic dogs, but also the small sample size, the variability or the narrowness of the panel (Herrmann et al., 2026).

A short Hungarian review proposes the omega-3 index to monitor the intake of these fatty acids in dogs. This index is the sum of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in red blood cell membranes, expressed as a percentage of total erythrocyte fatty acids. It can be measured on a dried blood spot. It reflects long-term intake, because red blood cell composition varies less than plasma with short-term dietary changes. Healthy dogs have a low baseline index. Supplementation with marine omega-3 fatty acids reliably raises it. In dermatology, however, erythrocyte data are very limited. There are still no species-specific reference intervals and no target values linked to clinical outcome (Tóth et al., 2026).

2 Noninflammatory alopecia, pigmentation and cortisol

2.1 Recurrent flank alopecia

Recurrent flank alopecia is a seasonal disease of dogs, with a strong breed predisposition. According to a Dutch narrative review, patches of alopecia appear when day length decreases, in fall or winter. They are usually located on the thoracolumbar flanks. These patches are symmetrical, well demarcated, noninflammatory and often hyperpigmented. Hair then regrows, partially or completely, the following spring or summer. The disease has no systemic effects. Diagnosis rests on signalment, clinical appearance, exclusion of differential diagnoses and histopathology, which varies with the stage and is suggestive without being pathognomonic. The mechanism appears multifactorial, combining photoperiod, neurohormonal influences and genetics. Treatment ranges from monitoring without treatment to melatonin. New options, such as low-level laser therapy, are emerging, but evidence from placebo-controlled trials remains limited (Verschuuren-Tjoeng et al., 2026a).

The same team looked for the genes involved in the Rhodesian Ridgeback. Low-coverage whole-genome sequencing, completed by imputation, was performed in 48 dogs, 24 affected and 24 controls. It was followed by genome-wide association studies and analysis of coding variants. Variants with a predicted functional effect were found in several genes, including EPB41L1 and DPY19L1. They are involved in the cytoskeleton, cell adhesion, nerve signaling and hair cycle pathways (Wnt, BMP, MAPK, Notch and Hedgehog). Flank alopecia would therefore be a genetically heterogeneous disease, influenced by several loci, rather than a simple monogenic disease. These genes remain candidates to be confirmed by functional studies (Verschuuren-Tjoeng et al., 2026b).

2.2 Radiation-induced alopecia

In dogs irradiated for a nasal tumor, coat type influences the risk of hair loss. A Japanese retrospective study reviewed the records of 38 dogs treated with radiation therapy. Dogs that lost their hair only after the end of treatment were excluded. Acute alopecia appeared during irradiation in 17 of the 34 dogs analyzed. Coat type was significantly associated with it: all dogs with curly or wire coats were affected. In these dogs, alopecia also appeared earlier than in straight-coated dogs, at a median of 14 days versus 20 days, and the difference was significant. In affected dogs, the areas receiving the highest skin dose lost their hair first, followed by less irradiated areas. Owners can thus be warned of the risk and timing of alopecia (Nemoto et al., 2026).

2.3 Feline hyperpigmentation and baseline cortisol

A clinical update addresses cutaneous hyperpigmentation in cats. Its record contains no abstract. Its content is therefore not analyzed here (Bajwa, 2026).

In dogs, a low baseline cortisol is more frequent after glucocorticoid exposure, which complicates screening for hypoadrenocorticism. A retrospective study reviewed 982 hospitalized dogs that underwent an ACTH stimulation test, 55 with hypoadrenocorticism and 927 without. A baseline cortisol of 2.0 µg/dL or less was significantly more frequent in the 198 dogs exposed to glucocorticoids (46.0%) than in the 729 unexposed dogs (31.0%). At this cutoff, the sensitivity of baseline cortisol was 98.2% and its specificity only 65.8%. Raising the cutoff to 2.4, 2.7 or 3.1 µg/dL improves sensitivity at the expense of specificity. A false-positive flat response to the stimulation test was observed in only 11 dogs (1.2%). The stimulation test therefore rules out hypoadrenocorticism in most dogs. It also provides prognostic information (Da Silva et al., 2026).

3 Bacterial and mycobacterial infections

3.1 Staphylococci

In India, 71 cases of PCR-confirmed staphylococcal pyoderma were analyzed from June to December 2024. Isolates were identified by MALDI-TOF mass spectrometry, then tested for antimicrobial susceptibility. Infection was monomicrobial in 63.38% of cases and polymicrobial in 36.62%. Staphylococcus pseudintermedius and Staphylococcus aureus dominated in both forms, alone or together with Escherichia coli, Pseudomonas aeruginosa or Klebsiella pneumoniae. Polymicrobial infection was significantly associated with recurrence, a longer course, tissue invasion and allergic skin manifestations. Both staphylococci showed high resistance to β-lactams and third-generation cephalosporins. Overall resistance did not differ significantly between mono- and polymicrobial infections, but isolates from polymicrobial infections tended to be more resistant, across several antibiotic classes. Species-level identification and culture-guided treatment should therefore be preferred (Sanwal et al., 2026).

In Naples, nasal swabs were collected from 100 dogs before surgery. They yielded 65 staphylococcal strains, identified by MALDI-TOF: S. pseudintermedius was the most frequent species (40%), ahead of S. aureus (15.4%) and S. epidermidis (7.7%). Resistance was high: 61.5% of strains were multidrug-resistant and 4.6% extensively drug-resistant. All strains tested formed a biofilm, moderately for most of them (56.9%), which could favor their persistence. Preoperative nasal screening is therefore proposed in high-risk patients, to adjust antimicrobial prophylaxis (Nocera et al., 2026).

In Brazil, the circulation of a methicillin-resistant S. pseudintermedius (MRSP) was followed in one household, starting from a postoperative osteomyelitis in the family dog. During the infection, in 2021, the ST71-SCCmec II-III lineage was found in the operated dog, in four family members and in the surgeon, i.e., 6 of 8 subjects colonized. The household’s other dog then carried a methicillin-resistant S. epidermidis. Two years later, MRSP was carried by this second dog and by two owners, i.e., 3 of 7 subjects. The ST71 lineage colonized the dog’s skin, and an emerging lineage, ST1095-CC551-SCCmec V, its nostrils and the two owners. Within each lineage, strains differed by no more than 8 point mutations, indicating recent transmission. MRSP therefore circulates durably between dogs and humans in the same household. One lineage can also replace another. The multidrug-resistant isolate remained susceptible to amikacin. The operated dog recovered after prolonged treatment with this drug and revision surgery (de Menezes et al., 2026).

Staphylococcus schleiferi causes skin and ear infections in dogs, but it is rarely described as a human pathogen. This staphylococcus does not produce coagulase. It is therefore easily confused with other species or dismissed as a contaminant. A case of acute prosthetic joint infection is reported in a patient with long-term occupational exposure to dogs. It was successfully treated with six weeks of intravenous antibiotics followed by three months of suppressive oral therapy (Wells et al., 2026).

3.2 Mycobacteria and severe soft tissue infections

A 4-year-old spayed female domestic shorthair cat had had draining wounds of the left thigh and left inguinal region for 8 months, unresponsive to empirical antibiotics. They had started with a cat bite on the thigh and a subcutaneous inguinal mass. Cytology of the mass had suggested a spindle cell tumor, but histopathology after excision showed severe necrotizing pyogranulomatous mastitis and dermatitis, with no tumor. Cultures of both lesions isolated Mycobacterium farcinogenes, identified by MALDI-TOF. The combination of pradofloxacin, topical amikacin gel and azithromycin led to complete remission within 24 weeks, without adverse effects, even though in vitro resistance had been found. This is the first feline case reported in Asia. It shows that an atypical mycobacterium must be identified to species level (Chuenngam et al., 2026).

Necrotizing fasciitis in dogs can become septic within one or two days. Two immunocompetent dogs from different households were referred for soft tissue wounds. A 5-year-old neutered male Golden Retriever had extensive hemorrhagic cellulitis of the forelimbs and neck, which developed within 48 hours. In an 8-year-old spayed female Labrador mix, a penetrating wound of the left hip progressed within 24 hours to necrotizing fasciitis. The bacteria involved were Acinetobacter lactucae and Bacillus paramobilis, one species in each dog. Histopathology showed severe acute muscle necrosis in both cases, with necrosuppurative myofasciitis, dermatitis and panniculitis containing rod-shaped bacteria. Genome sequencing revealed numerous cytolytic toxins and other virulence genes. These two species had never before been associated with necrotizing fasciitis in dogs (Greenberg et al., 2026).

Melioidosis, caused by Burkholderia pseudomallei, is a severe and potentially fatal infection of dogs and cats. It occurs in tropical, and sometimes subtropical, regions of Australia. A series of 45 cases, 24 dogs and 21 cats, was collected over 27 years in the Northern Territory and Queensland. Cases occurred mainly during the wet season, from December to March. The most frequent forms were primary neurological disease or localized infection (wound, cellulitis or abscess). Dogs more often had skin and subcutaneous involvement, whereas cats showed more varied forms. In most cases, no predisposing cause, such as immunosuppression, was found. Among the 15 animals with a known outcome, all 4 dogs recovered. Of the 11 cats, 5 recovered and 4 were euthanized. Across the whole series, 13 animals died or were euthanized because of the disease, 7 of which had a neurological form. Rapid diagnosis and appropriate antibiotic therapy without delay therefore determine control of the infection (Lee et al., 2026).

3.3 Skin flora of guinea pigs

In guinea pigs, a Canadian cross-sectional study compared the skin flora of 46 animals over 4 years: 16 healthy, 16 with skin disease and 14 with nondermatological disease. Staphylococcus xylosus was the most frequent bacterium, ahead of Aerococcus viridans. S. aureus, although associated with guinea pig skin diseases in previous publications, was not isolated from any lesion. Malassezia yeasts were visible on cytology, but none grew in culture, which suggests that other techniques are needed to identify them. No dermatophytes were found in guinea pigs without skin disease (Foster et al., 2026).

4 Mycoses and related infections

Feline histoplasmosis is rarely diagnosed in Europe, and it had never been diagnosed in Northern Europe or the Baltic countries. Three clustered autochthonous cases are reported in Latvia in domestic shorthair cats with ulcerated or eroded skin lesions. Cytology showed organisms consistent with Histoplasma in all three cases. The first cat, positive for feline immunodeficiency virus and living in a shelter, had multiple ulcers. Histopathology and immunohistochemistry confirmed a mycosis suggestive of Histoplasma, then the cat was lost to follow-up. The second, a 3-year-old male with a single erosive facial lesion, recovered with antifungal treatment. The third, a 6-year-old neutered male with multiple erosive lesions, was euthanized. In this cat, H. capsulatum antigen testing was positive in urine and serum. PCR followed by sequencing provided the first molecular confirmation of Histoplasma capsulatum in the Baltic region. Cytology is therefore a good first-line test. Serology and molecular methods complement it where established mycological methods are poorly accessible. Histoplasmosis may be underdiagnosed outside endemic areas (Berzina et al., 2026).

In Italy, 7 autochthonous cases of canine pythiosis were recognized between 2021 and 2024. All the dogs had been exposed to fresh water. The cases involved several lakes, over consecutive years. The sequenced isolates belonged to clade IV of the Pythium insidiosum complex, now designated Pythium periculosum (Peano et al., 2026).

Arthroderma uncinatum, a geophilic dermatophyte, was identified in an 11-month-old English Setter from southern Italy with two alopecic, erythematous and scaly lesions of the metacarpal and metatarsal regions. Microscopic examinations had been inconclusive, but culture isolated the fungus, identified by sequencing of the ITS region. Topical 1% clotrimazole applied for three weeks achieved clinical and mycological cure (Samarelli et al., 2026).

In Tehran, in a Shih Tzu with pruritus and scaling, a fungus isolated from a skin scraping was identified as Corynascus verrucosus. Microscopy and culture could not name the species. The ITS region was therefore amplified and sequenced. The sequence was 99.36% identical to a C. verrucosus reference sequence. Phylogenetic analysis placed it in the Corynascus lineage. The large, round, warty conidia were also consistent. Closely related species, however, share very similar sequences. The molecular result must therefore be interpreted with caution. The abstract reports neither treatment nor outcome (Ghahremani et al., 2026).

In a 2-year-old neutered male Chihuahua mix living in Tasmania, Prototheca wickerhamii caused a localized cutaneous form: the metacarpal and metatarsal pads were swollen, painful and ulcerated, with marked lameness. Diagnosis was based on cytology, histopathology, culture and MALDI-TOF. Modified pulse itraconazole was ineffective. Oral posaconazole resolved the signs, but it had to be continued: the disease relapsed when treatment was stopped. Intralesional amphotericin B deoxycholate then achieved lasting remission, possibly a cure. In dogs, protothecosis is usually disseminated after primary colonic involvement. Its prognosis for cure is poor. This case therefore broadens the known picture to a localized cutaneous form in a temperate climate (Sahebjam et al., 2026).

5 External parasites and otology

In Switzerland, Onchocerca lupi caused severe unilateral otitis externa with mass formation in a dog. The diagnosis was confirmed by molecular analysis after extraction of the nematode. Combined treatment led to complete remission within 6 weeks. This is the first successfully treated aural case in Switzerland. O. lupi therefore belongs in the differential diagnosis of chronic otitis with a mass (Martini et al., 2026).

Lynxacarus radovskyi infestation was treated in 16 client-owned cats, recruited from three clinics, with a single application of the topical combination of esafoxolaner, eprinomectin and praziquantel (NEXGARD COMBO®). The minimum doses were 1.4 mg/kg esafoxolaner, 0.5 mg/kg eprinomectin and 5 mg/kg praziquantel. Depending on the case, the cats had pruritus, alopecia and scaling. On Day 30, no mites were detected in any cat, and clinical signs had improved markedly. No adverse effects were observed. This pilot study was, however, open-label and had no untreated control group: each cat served as its own control (Beugnet et al., 2026).

A review summarizes the topical combination of selamectin and sarolaner in cats (STRONGHOLD PLUS® in the European Union). The minimum doses of this combination are 6.0 mg/kg selamectin and 1.0 mg/kg sarolaner, applied monthly. The two drugs act on fleas through different modes of action. Their combination therefore kills fleas quickly and effectively, which reduces egg laying, flea allergy dermatitis and the risk of Dipylidium caninum infection. Against ten tick species, efficacy exceeds 90% for at least four weeks after a single application. Against mites, a single dose is highly effective against Otodectes cynotis and completely eliminates Notoedres cati within 30 days. Demodex infestations have been treated successfully with one or more applications (Geurden et al., 2026).

Several fleas, including those of the genus Ctenocephalides, can bite humans. A letter from dermatologists in Milan recalls that these bites form pruritic erythematous papules, isolated or clustered. They are most often located on the legs and ankles, because fleas have no wings but jump up to 30 cm off the ground. The record gives only the beginning of the letter. The explanation for locations on the upper limbs and trunk, the subject of the title, is therefore not analyzed here (Veraldi et al., 2026).

In Isfahan, Iran, 138 randomly selected dogs were examined from July 2023 to July 2024: 57 stray dogs, 38 herding dogs and 43 owned dogs. Ectoparasites were found in 54 of them. Ticks were the most frequent (26 dogs), ahead of mites (15), fleas (9) and lice (4). Prevalence varied significantly with sex and age. Infestation peaked in spring (Rafiyan et al., 2026).

6 Canine leishmaniasis

Canine leishmaniasis has spread in Italy toward the center and north, regions once considered free of the disease. A team including the WOAH reference laboratory for Leishmania, in Palermo, estimated incidence by province for 2022 and 2023. It related newly diagnosed cases to a dog population approximated from ISTAT demographic data, assuming one dog for every five inhabitants. Incidence ranged from 0 to nearly 500 cases per 10,000 dogs. By this criterion, 49 provinces were at minimal risk and 30 at low risk. The others were at moderate (21), high (4) or very high (4) risk. Low categories dominated in the north and center, high categories in the south and Sicily, but two provinces in Liguria, Imperia and Savona, were at very high risk. Absolute values depend on the chosen denominator. This estimate is therefore used to rank areas rather than to measure the exact burden of the disease (Bruno et al., 2026).

Dogs are the main urban reservoir of Leishmania infantum, hence the interest in a vaccine. In 120 female BALB/c mice, a heterologous vaccination was compared with other regimens. It combined a recombinant adenovirus carrying the amastigote A2 antigen, followed by the recombinant protein vaccine Leish-Tec. After challenge infection with L. infantum, this vaccination strongly reduced the bone marrow parasite load, and parasite DNA became undetectable there in most mice. It also induced robust cellular immunity, with more CD4 T cells producing TNF-α and IFN-γ. The Leish-Tec regimen alone, for its part, gave the highest anti-A2 antibody titers. These results come from a mouse model. They therefore remain to be confirmed in dogs (Amado-Gomes et al., 2026).

7 Skin oncology

7.1 Mast cell tumors

Three-phase computed tomography helps distinguish cutaneous or subcutaneous mast cell tumors from benign lesions. A Japanese retrospective case-control study compared 23 mast cell tumors with 7 benign lesions. The mast cell tumors measured 3 cm or more in 10 cases and less than 3 cm in 13. Large mast cell tumors were recognized by qualitative signs: heterogeneous contrast enhancement, feeding vessels, infiltration, necrosis and stranding of the adjacent fat. Small mast cell tumors lacked these signs, but their attenuation was significantly higher than that of benign lesions in the portal and equilibrium phases. At a cutoff of 68.7 Hounsfield units in the portal phase, sensitivity was 92% and specificity 71%. At a cutoff of 74.7 units in the equilibrium phase, sensitivity was 92% and specificity 57%. The sample size, however, remains small (Morishita et al., 2026).

Plasma histamine was studied as a prognostic marker in 27 dogs operated on for mast cell tumors, for 29 surgeries over 28 months. A preoperative plasma histamine above 1.0 ng/mL was associated with a significantly shorter progression-free interval. But, in dogs with cutaneous mast cell tumors, multivariate analysis showed that this histamine level depended on tumor volume and did not remain an independent prognostic factor. Postoperative plasma histamine, rarely elevated, was associated with gross residual tumor, but it may lack sensitivity for microscopic disease. Plasma histamine therefore complements the usual criteria without replacing them. This exploratory study must be validated by larger prospective studies (Niwa et al., 2026).

Raman spectroscopy, a nondestructive optical technique, was tested to distinguish low-grade from high-grade cutaneous mast cell tumors, according to the Kiupel two-tier grading system. Eighteen formalin-fixed tumors, 10 low-grade and 8 high-grade, provided 68 spectra. The band at 860 cm⁻¹, related to tyrosine, was significantly more intense in high-grade tumors. Conversely, several ratios normalized to the phenylalanine band at 1,007 cm⁻¹ were significantly higher in low-grade tumors. The study remains exploratory, to be validated in larger cohorts with clinical outcome data (Catarino et al., 2026).

7.2 Lymphangiosarcoma

A 9-year-old neutered male Australian Cattle Dog had severe, extensive and progressive swelling of the neck and face. CT lymphography of the head and neck showed cervical lymphedema, with mid-cervical lymphatic obstruction, regional lymphatic leakage and local lymphadenopathy. Histopathology concluded lymphangiosarcoma, considered the cause of the obstruction. This is the first description of this imaging technique as a diagnostic aid for lymphangiosarcoma in dogs (Bleuet et al., 2026).

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