## 3 PDT in Veterinary Oncology
### Sarcomas
\begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline
**Ref.** & **Neoplasm** & **Patients** & **PDT Protocol** & **Main Results** \\ \hline
[101] & Mastocytoma (Lips) & 1 Cat & **PS:** HPD, 5.0 mg/kg, iv **Light:** Argon laser, 324 J/cm\({}^{2}\), 631 nm, 2 sessions & \(\bullet\) & Recurrence at five months after the first treatment **\(\bullet\)** & Recurrence at five months after the first treatment **\(\bullet\)** & Recurrence at two months after the second treatment **\(\bullet\)** \\ \hline
[101] & Mastocytoma (Lips) & 1 Dog & **PS:** HPD, 5.0 mg/kg, iv **Light:** Argon laser, 103 J/cm\({}^{2}\), 631 nm, 1 session & \(\bullet\) & Cured at the six months follow-up **\(\bullet\)** \\ \hline
[71] & Mast cell tumor & 1 Dog & **PS:** 5-ALA, 40 mg/kg, oral **Light:** LED, 60 J/cm\({}^{2}\), 635 nm, 1 session & \(\bullet\) & Complete response and stable disease \\ \hline
[107] & Mast cell tumor & 2 Dogs & **PS:** PAD-S31, 15 mg/kg, iv **Light:** Argon laser, 150 J/cm\({}^{2}\), 670 nm, 1 session & \(\bullet\) & Slight depigmentation immediately after irradiation **\(\bullet\)** & Immediately after irradiation **\(\bullet\)** & No recurrence was observed during the sixth and seventh **\(\bullet\)** \\ \hline
[96] & Mast cell tumor & 2 Dogs & **PS:** EtNBS, 2.0 mg/kg, iv **Light:** Diode laser, 100–400 J/cm\({}^{2}\), 652 nm, 1–2 sessions & \(\bullet\) & Brief and complete response **\(\bullet\)** \\ \hline
[113] & Mast cell tumor & 1 Dog & **PS:** CASPC, 1.0 mg/kg, iv **Light:** Argon laser, 50–100 J/cm\({}^{2}\), 675 nm, 1 session & \(\bullet\) & Complete response **\(\bullet\)** \\ \hline
[84] & Mast cell tumor & 1 Dog & **PS:** ZnPcS\({}_{4}\), 4.0 mg/kg, iv **Light:** Diode laser, 100 J/cm\({}^{2}\), 675 \(\pm\) 0.2 nm, 1 session & \(\bullet\) & Partial response **\(\bullet\)** \\ \hline  & & Legend: 5-ALA, 5-aminolevulinic acid; CASPc, chloro-aluminum sulfonated phthalocyanine; EtNBS, 5-ethylamino-9-diethylaminobenzo(a)phenothiazinium chloride; iv; intravenous; HPD, hematoporphyrin derivative; PAD-S31, 13,17-bis [1-carboxyproionyl] carbamoylylethyl3-5-ethenyl-8 ethoviminoethylidene-7-hydroxy-2,7,12,18-tetramethyl porphyrin sodium; PS, photosensitizer; ZnPcS\({}_{4}\), zinc phthalocyanine tetrasulfonate. & \(\bullet\) \\ \hline  & & Legend: 5-ALA, 5-aminolevulinic acid; CASPc, chloro-aluminum sulfonated phthalocyanine; EtNBS, 5-ethylamino-9-diethylaminobenzo(a)phenothiazinium chloride; iv; intravenous; HPD, hematoporphyrin derivative; PAD-S31, 13,17-bis [1-carboxyproionyl] carbamoylylethyl3-5-ethenyl-8 ethoviminoethylidene-7-hydroxy-2,7,12,18-tetramethyl porphyrin sodium; PS, photosensitizer; ZnPcS\({}_{4}\), zinc phthalocyanine tetrasulfonate. & \(\bullet\) \\ \hline \end{tabular}
\end{table} 
Table 2: Clinical studies on PDT in animals with mastocytomas. HPPH-based PDT was used as adjuvant therapy in 16 dogs with hemangiopericytoma. Most of the 16 animals treated have recurred (56%) [121]. PDT with HPPH was performed in a dog with intranasal chondrosarcoma. The right and left nasal passages were treated with PDT. A second PDT treatment was performed; however, the dog was euthanized two weeks later because of progressive disease [109]. CASPc-based PDT was administered to three dogs with fibrosarcoma and four with hemangiopericytoma. Of the three animals with fibrosarcoma, one had no response, one had recurrence after nine months, and the other had regional metastasis in 15 months and a relapse after 18 months of treatment [83]. In the case of the hemangiopericytoma patients, the masses were surgically excised, and PDT was performed seven days later. An average remission period of 9 to 21 months (mean of 15.25) was observed [83]. The same approach was performed on a dog with undifferentiated sarcoma in the abdominal wall after surgical and adjuvant treatment failure. However, the patient was lost due to metastatic disease [113].