New trends in nuclear oncology: current problems in diagnosis of neoplastic diseases

The diagnosis of oncologic diseases requires four levels of imaging intervention: identification, characterization, staging, and follow-up. Diagnostic problems in the identification of neoplastic disease may be present both for screening and for symptomatic patients; until today, few screening studies have been organized (e.g., screening for carcinoma of cervix); the realization of similar programs for other kinds of neoplastic disease could be useful. In the characterization of neoplastic masses, imaging signs are often pathognomonic. Moreover, the approach with imaging-guided biopsy is often diagnostic. In some cases, interventional radiologic procedures are not indicated, and only the integration of radiologic techniques like spiral CT and/or MRI with techniques of nuclear-medicine such as positron emission tomography (PET) can tackle the problem. Problems concerning the staging and/or restaging of neoplasms are even more complex: In general terms, radiologic imaging is, in our opinion, a good way to solve problems about local staging (T), whereas it seems to be less accurate in detecting distant small lesions (M), neoplastic lymph nodes (N), or in distinguishing fibrous tissue after therapy (chemo, surgical or radiotherapy) from neoplastic relapse. This paper describes the usefulness of integrated research in oncology between radiologic and functional imaging.