Targeted therapies are designed to interfere with specific aberrant biologic pathways involved in tumor development. The main classes of novel oncologic drugs include antiangiogenic drugs, antivascular agents, drugs interfering with EGFR-HER2 or KIT receptors, inhibitors of the PI3K/Akt/mTOR pathway, and hormonal therapies. Cancer cells usurp normal signal transduction pathways used by growth factors to stimulate proliferation and sustain viability. The interaction of growth factors with their receptors activates different intracellular pathways affecting key tumor biologic processes such as neoangiogenesis, tumor metabolism, and tumor proliferation. The response of tumors to anticancer therapy can be evaluated with anatomic response assessment, qualitative response assessment, and response assessment with functional and molecular imaging. Angiogenesis can be measured by means of perfusion imaging with computed tomography and magnetic resonance (MR) imaging. Diffusion-weighted MR imaging allows imaging evaluation of tumor cellularity. The main imaging techniques for studying tumor metabolism in vivo are positron emission tomography and MR spectroscopy. Familiarity with imaging findings secondary to tumor response to targeted therapies may help the radiologist better assist the clinician in accurate evaluation of tumor response to these anticancer treatments. Functional and molecular imaging techniques may provide valuable data and augment conventional assessment of tumor response to targeted therapies. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.317115108/-/DC1.

Functional imaging now has a growing role in colorectal cancer. Recent developments in imaging technologies and validation of these newer imaging techniques may lead to significant improvements in the management of patients with colorectal cancer.

The detection of somatic mutations in rectal cancer tumors led us to re-evaluate the utility of the tests performed in blood samples for these polymorphisms in rectal cancer. Furthermore, studies aimed at assessing the influence of pharmacogenetic markers in treatment response performed in blood samples should take into account the particular pattern of hypermutability present in each tumor type. We hypothesize that different patterns of hypermutability present in each tumor type would be related to the different results in association studies related to response to the treatment.

During heart-lung or double lung transplantation, the airway anastomosis is usually made at the tracheal level. Healing of this anastomosis is one source of postoperative complications especially after double lung transplantation (DLT). In this series of 10 patients with cystic fibrosis undergoing DLT, the tracheas of donor and recipient were anastomosed with omental wrapping in 2 cases while the two main stem bronchi were joined without omental wrapping in 8. Endoscopy disclosed no sign of ischaemia in the patients with bilateral bronchial anastomoses. Three patients died on day 20, 21 and 35, respectively, after DLT. Two of these patients (one with a tracheal and the other with bronchial anastomoses) showed no complication at the level of the suture line. The third patient (with bronchial suture) suffered dehiscence of both anastomoses which was attributed to a misdosage of corticosteroids. Of the 6 patients alive after bronchial anastomosis, 3 recovered uneventfully and 3 who had required prolonged postoperative mechanical ventilation developed bronchomalacia. Bronchomalacia was treated by laser resection and stenting. Dehiscence did not occur in any of these six cases. This technique was based on the findings of 12 fresh cadaver dissections showing that collaterals between the bronchial arteries and the pulmonary arteries and veins extend up to the origin of the main stem bronchus. Bronchial suture without omental wrap may be used for double lung and heart-lung transplantation instead of tracheal suture.