Informational needs of patients with melanoma and their views on the utility of investigative tests

BACKGROUND

The aim of the study was to identify the informational needs of patients with melanoma on disease status and prognosis, and to ascertain their views on the utility of positron emission tomography (PET) and sentinel node biopsy (SNB).

PATIENTS AND METHODS

Patients attending the weekly melanoma outpatient clinic at St Thomas' Hospital London UK between February and August 2007 participated in this cross-sectional survey. Views of 106 melanoma patients were elicited using a face-to face semi-structured questionnaire.

RESULTS

The majority of participants wanted to know everything about their disease (88%). Prognostic information (> 85%) and information on palliative care input (97%) were highly valued. More than 50% expected the doctor to impart this information without negotiation. Nearly 70% of the responders who had previously had a PET scan felt they should decide if and when the scans should be performed. Fifty three percentage had undergone the SNB because the doctor had suggested it.

CONCLUSIONS

Patients with melanoma want detailed and prompt information about their disease including prognosis. Regular PET scans provide reassurance. The role of SNB is not clear to all patients.

TRIPAS: a triapplicator system with relocatable 'hot spot' at tissue depth

Solving the problem of heat focusing and standardization of the clinical application of hyperthermia requires a mathematical prediction model. The model should include the medium constitutive parameter, and be able to predict positioning of the microwave applicators to optimize treatment planning and provide for reproducible treatment set-up. We present a configuration of 3 applicators subtended by an equilateral triangle in order to target and relocate a 'hot spot' for improved treatment of deep tumors. A simple geometric analysis is illustrated. The microwave beam absorption profile, from the three power sources, was obtained from phantom studies depicting the radiative heat pattern for the triapplicator system (TRIPAS). A complex mathematical model was developed to demonstrate interaction of the beams in the medium. It was observed empirically that under coherent propagation in the near field electromagnetic (EM) waves tend to add at the center, while varying the propagation axial focal length caused a relocation of the summing focal points. Mathematical prediction correlated very well with the phantom studies. SAR values above 100 W/kg were achieved at 12.5 cm phantom depth, creating a relocatable 'hot spot' at the concentric foci of the 3 air cooled horn microwave applicators operating at 300 MHz.