manganese(iii)tetraphenylporphine-sulfonate and Skin-Neoplasms

The aim of this study was to evaluate the potential of the paramagnetic metalloporphyrin Mn-TPPS4 (using Gd-DTPA as the reference) for magnetic resonance imaging (MRI) of pigmented malignant melanoma in an animal model. High resolution MRI (2.0 T, 2.0 cm surface coil, T1-weighted FLASH two-dimensional sequence) was performed on 15 mice (C57bl6) with intracutaneous implanted melanoma (B16F1) before and after intravenous administration of Gd-DTPA (Magnevist, Schering AG, Berlin, Germany) and Mn-TPPS4 (Porphyrin Products, Logan, Utah, USA). The images were evaluated quantitatively by calculating the percentage enhancement, the slope of the signal intensity-to-time curves, the percentage increase in the signal intensity, and the signal-to-noise and contrast-to-noise ratios. The qualitative evaluation was accomplished by visual assessment of the enhancement, the demarcation of the tumours from the surrounding tissue, and the homogeneity of the tumours. Contrast medium-enhanced images showed an increase in signal intensity for all the tumours, with no significant difference between the contrast media. Specific accumulation of the contrast media in the melanoma could not be proved. Demarcation of tumours from the surrounding tissue is better after administration of contrast media; regressive changed areas were better depicted.

Topics: Animals; Contrast Media; Female; Gadolinium DTPA; Injections, Intravenous; Magnetic Resonance Imaging; Melanoma, Experimental; Metalloporphyrins; Mice; Mice, Inbred C57BL; Neoplasm Transplantation; Skin Neoplasms; Skin Pigmentation; Tumor Cells, Cultured

Some authors postulate an avidity of certain porphyrin derivatives for tumors. The aim of this study was to examine the contrast enhancement of implanted melanotic melanoma after application of Mn-TPPS4 to achieve a better characterization of this malignant skin tumor.. High-resolution MR imaging (2.0 Tesla, 2.0-cm surface-coil, T1-weighted FLASH-2D-sequence) was performed on 15 mice (C57b16) with intracutaneous implanted melanoma (B16F1), before and after intravenous administration of either Gd-DTPA (Magnevist, Schering, Berlin) as a reference contrast medium, or Mn-TPPS4 (Porphyrin Products, Schering, Berlin). The images were evaluated quantitatively by calculating percentage enhancement, slope of signal intensity-to-time curves, percentage increase of the signal intensity, signal-to-noise and contrast-to-noise-ratios. The qualitative evaluation was accomplished by visual assessment of the enhancement, the demarcation of the tumors from the surrounding tissue and the homogeneity of the tumors.. Contrast medium-enhanced images showed an increased signal intensity from all tumors with no signifikant difference between the contrast media. Demarcation of tumors from the surrounding tissue was better following administration of contrast media; regressive and altered areas was more clearly depicted.. A specific accumulation of the metalloporphyrin Mn-TPPS4 in melanotic melanoma could not be proved. Based on the small and insignifikant differences in the results obtained with the two contrast media, and on the side effects of the metalloporphyrin, the usefulness of Mn-TPPS4 as a contrast medium for MRT is limited.

Topics: Animals; Contrast Media; Disease Models, Animal; Gadolinium DTPA; Humans; Image Enhancement; Magnetic Resonance Imaging; Melanoma; Metalloporphyrins; Mice; Skin Neoplasms; Tomography

Nine patients with cutaneous metastases of breast cancer were treated using photodynamic therapy. Meso-tetra-(para-sulphophenyl)-porphin (TPPS4) was applied locally at a dose of 0.15-0.3 mg directly to the lesion. The light source was an argon dye laser emitting light of 630 nm at a fluence rate of 312-680 mW cm-2 and a fluence of 150 J cm-2. No signs of local or systemic side effects or toxicity of the photosensitizer were observed. Treatments were well tolerated with no photosensitivity of the skin. Complete destruction of the tumour was observed in three patients, reduction of the tumour size by more than 50% in two patients, reduction-of the tumour size by less than 50% in two patients and no regression in two patients. The advantages of this method include the high concentration of the photosensitizer in the tumour, the extremely low total dose and the lack of side effects. The disadvantages include the less homogeneous distribution of the photosensitizer in the tumour tissue compared with that obtained by intravenous application.

Topics: Aged; Breast Neoplasms; Contrast Media; Female; Humans; Lasers; Manganese; Mastectomy; Metalloporphyrins; Middle Aged; Neoplasm Recurrence, Local; Photochemotherapy; Skin Neoplasms