Electrochemotherapy with cisplatin enhances local control after surgical ablation of fibrosarcoma in cats: an approach to improve the therapeutic index of highly toxic chemotherapy drugs

Background

Cancer is one of the most difficult current health challenges, being responsible for millions of deaths yearly. Systemic chemotherapy is the most common therapeutic approach, and the prevailing orientation calls for the administration of the maximum tolerated dose; however, considerable limitations exist including toxicities to healthy tissues and low achievable drug concentrations at tumor sites. Electrochemotherapy (ECT) is a tumor treatment that combines the systemic or local delivery of anticancer drugs with the application of permeabilizing electric pulses. In this article we evaluate the capability of ECT to allow the use of cisplatin despite its high toxicity in a spontaneous feline model of soft tissue sarcoma.

Methods

A cohort of sixty-four cats with incompletely excised sarcomas were treated with cisplatin-based adjuvant ECT and monitored for side effects. Their response was compared to that of fourteen cats treated with surgery alone.

Results

The toxicities were minimal and mostly treated symptomatically. ECT resulted in increased local control (median not reached at the time of writing) with a mean time to recurrence of 666 days versus 180 of controls.

Conclusions

We conclude that ECT is a safe and efficacious therapy for solid tumors; its use may be considered as part of strategies for the reintroduction of drugs with a narrow therapeutic index in the clinical protocols.

Definition of an automated Content-Based Image Retrieval (CBIR) system for the comparison of dermoscopic images of pigmented skin lesions

Background

New generations of image-based diagnostic machines are based on digital technologies for data acquisition; consequently, the diffusion of digital archiving systems for diagnostic exams preservation and cataloguing is rapidly increasing. To overcome the limits of current state of art text-based access methods, we have developed a novel content-based search engine for dermoscopic images to support clinical decision making.

Methods

To this end, we have enrolled, from 2004 to 2008, 3415 caucasian patients and collected 24804 dermoscopic images corresponding to 20491 pigmented lesions with known pathology. The images were acquired with a well defined dermoscopy system and stored to disk in 24-bit per pixel TIFF format using interactive software developed in C++, in order to create a digital archive.

Results

The analysis system of the images consists in the extraction of the low-level representative features which permits the retrieval of similar images in terms of colour and texture from the archive, by using a hierarchical multi-scale computation of the Bhattacharyya distance of all the database images representation with respect to the representation of user submitted (query).

Conclusion

The system is able to locate, retrieve and display dermoscopic images similar in appearance to one that is given as a query, using a set of primitive features not related to any specific diagnostic method able to visually characterize the image. Similar search engine could find possible usage in all sectors of diagnostic imaging, or digital signals, which could be supported by the information available in medical archives.

Malignant melanoma associated with a blue naevus: a case report

INTRODUCTION

Combined malignant naevi are characterised pathologically by the association of a melanoma with one or more different types of benign melanocytic naevi in a single lesion.

CASE PRESENTATION

We show here a case of malignant combined naevus made up of a blue naevus and a melanoma, presenting as a slowly progressing and asymptomatic pigmented lesion on the trunk of a 35-year-old man. Dermoscopic examination was not conclusive for a malignant lesion, showing only an atypical brown pigment network. The definitive diagnosis was reached only at the hystopathological examination.

CONCLUSION

This finding suggests that combined naevi should be always excised and histologically examined to achieve a correct diagnosis and avoid risk of misclassification.

Role of Apaf-1, a key regulator of apoptosis, in melanoma progression and chemoresistance

Apoptosis protease-activating factor-1 (Apaf-1) is a key regulator of the mitochondrial apoptotic pathway, being the central element of the multimeric apoptosome formed by procaspase 9, cytochrome c, and Apaf-1 itself. In this review, the principal aspects about Apaf-1 gene structure and function, and its role in the apoptotic machinery, are described. Moreover, the most recent findings about the involvement of this molecule in melanoma progression and chemoresistance, as well as the clinico-pathological relevance of these findings in the treatment of this deadly disease, are reported.

Spontaneous intestinal melanoma in dogs

Primary melanoma of the gastrointestinal tract is a rare, highly malignant neoplasm that is associated with an unfavorable long-term prognosis. Animal studies are needed to further characterize this tumor and to develop new and more effective protocols. A spontaneous canine intestinal melanoma is described which, because of its local aggressive behavior and advanced stage, was not treatable with conventional strategies, thus being a potential candidate for investigational trials.

Analysis of APAF-1 expression in human cutaneous melanoma progression

APAF-1 plays a pivotal role in mitochondria-dependent apoptosis, binding to cytochrome c and favoring activation of caspase-9. It has been shown that epigenetic silencing of the APAF-1 gene is a common event in several metastatic melanoma cells in vitro. We determined, by Western blot, variation in the level of expression of APAF-1 in several human melanoma cell lines and, by immunohistochemistry, in a group of 106 histological samples including benign and malignant melanocytic lesions. We observed APAF-1 down-regulation or loss of expression in two metastatic melanoma cell lines, compared to primary melanoma cell lines. The immunohistochemical analysis revealed a significant difference in APAF-1 staining between nevi and melanomas. In addition, we found a significant negative correlation between APAF-1 expression level and tumor thickness and between primary melanomas and metastases. We conclude that loss of APAF-1 expression can be considered as an indicator of malignant transformation in melanoma.