Introduction: molecular imaging and oncology -- Magnetic resonance -- Magnetic resonance spectroscopy (MRS) -- Basics of signal processing for Magnetic resonance -- Magnetic resonance spectroscopic imaging (MRSI) -- Safety considerations -- Magnetic resonance in cancer diagnostics-generalities -- Brain tumor diagnostics -- Prostate cancer diagnostics -- Gynecologic cancers -- Head and neck cancer -- Non-Hodgkin's Lymphoma (NHL) -- Sarcomas-Musculoskeletal tumors -- Renal cell carcinomas (RCC) -- Hepatic, GI and other tumors -- Breast cancer-Screening and early diagnosis -- Limitations of MRS and MRSI in oncology: Relation to reliance on the conventional framework for data analysis -- Mathematical advances in spectral analysis: Potential relevance for cancer diagnostics using MRS and MRSI -- Next needed steps-Application of the FPT with the aim of optimisation of MRSI in cancer diagnosis -- Concluding comments and outlooks: Prevention, early detection, and monitoring of cancer in a more comprehensive perspective