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This paper looks more closely at the sources of patent growth in the United States since 1984. It confirms that the increase is largely due to U.S. patenters, with an earlier surge in Asia, and some increase in Europe. Growth has taken place in all technologies, but not in all industries, being concentrated in the electrical, electronics, computing, and scientific instruments industries. It then examines whether these patents are valued by the market. We know from survey evidence that patents in these industries are not usually considered important for appropriability, but are sometimes considered necessary to secure financing for entering the industry. I compare the market value of patents held by entrant firms to those held by incumbents (controlling for R&D). Using data on publicly traded firms 1980–1989, I find that in industries based on electrical and mechanical technologies the market value of entrants’ patents is positive in the post-1984 period (after the patenting surge), but not before, when patents were relatively unimportant in these industries. Also, the value of patent rights in complex product industries (where each product relies on many patents held by a number of other firms) is much higher for entrants than incumbents in the post-1984 period. For discrete product industries (where each product relies on only a few patents, and where the importance of patents for appropriability has traditionally been higher), there is no difference between incumbents and entrants.

Adaptive radiotherapy system is designed to systematically manage treatment feedback, planning, and adjustment in response to temporal variations occurring during the radiotherapy course. A temporal variation process, as well as its subprocess, can be classified as a stationary random process or a nonstationary random process. Image feedback is normally designed based on this classification, and the imaging mode can be selected as radiographic imaging, fluoroscopic imaging, and/or 3D/4D CT imaging, with regard to the feature and frequency of a patient anatomical variation, such as rigid body motion and/ or organ deformation induced by treatment setup,organ filling, patient respiration, and/or dose response. Parameters of a temporal variation process, as well as treatment dose in organs of interest, can be estimated using image observations. The estimations are then used to select the planning/adjustment parameters and the schedules of imaging, delivery, and planning/adjustment. Based on the selected parameters and schedules, 4D adaptive planning/adjustment are performed accordingly.

Adaptive radiotherapy represents a new standard of radiotherapy, where a “pre-designed adaptive treatment strategy” a priori treatment delivery will replace the “pre-designed treatment plan” by considering the efficiency, optima, and also clinical practice and cost.

This paper looks more closely at the sources of patent growth in the United States since 1984. It confirms that the increase is largely due to U.S. patenters, with an earlier surge in Asia, and some increase in Europe. Growth has taken place in all technologies, but not in all industries, being concentrated in the electrical, electronics, computing, and scientific instruments industries. It then examines whether these patents are valued by the market. We know from survey evidence that patents in these industries are not usually considered important for appropriability, but are sometimes considered necessary to secure financing for entering the industry. I compare the market value of patents held by entrant firms to those held by incumbents (controlling for R&D). Using data on publicly traded firms 1980–1989, I find that in industries based on electrical and mechanical technologies the market value of entrants’ patents is positive in the post-1984 period (after the patenting surge), but not before, when patents were relatively unimportant in these industries. Also, the value of patent rights in complex product industries (where each product relies on many patents held by a number of other firms) is much higher for entrants than incumbents in the post-1984 period. For discrete product industries (where each product relies on only a few patents, and where the importance of patents for appropriability has traditionally been higher), there is no difference between incumbents and entrants.

Local recurrences after conservative surgery and WBRT are most likely to occur in the immediate vicinity of the lumpectomy site. This fact has prompted the investigation of new approach of limited-field RT. Brachytherapy using either low or high dose rates delivering the total dose during a few days after surgery is advocated by several teams. While with interstitial brachytherapy the first results at 5 years are promising, the results with the MammoSite balloon device are still immature with a relatively short follow-up. The balloon catheter applicator has been developed in North America because of the theoretical disadvantages reported after the standard catheter-based interstitial brachytherapy. In the U.S. very few clinicians are familiar with the technique: many patients and health care find the placement, appearance, and the numerous puncture sites disturbing. If a simpler, safer, and quicker technique for the delivery of radiation could be offered to patients with early-stage breast cancer, such an approach could theoretically increase the breast-conserving therapy option to more women and improve their quality of life.

Accelerated PBI is logistically simpler and a more practical method for breast-conserving therapy, but it has to be demonstrated in randomized phase-III trials that it is at least equivalent to WBRT before its routine use.

Local recurrences after conservative surgery and WBRT are most likely to occur in the immediate vicinity of the lumpectomy site. This fact has prompted the investigation of new approach of limited-field RT. Brachytherapy using either low or high dose rates delivering the total dose during a few days after surgery is advocated by several teams. While with interstitial brachytherapy the first results at 5 years are promising, the results with the MammoSite balloon device are still immature with a relatively short follow-up. The balloon catheter applicator has been developed in North America because of the theoretical disadvantages reported after the standard catheter-based interstitial brachytherapy. In the U.S. very few clinicians are familiar with the technique: many patients and health care find the placement, appearance, and the numerous puncture sites disturbing. If a simpler, safer, and quicker technique for the delivery of radiation could be offered to patients with early-stage breast cancer, such an approach could theoretically increase the breast-conserving therapy option to more women and improve their quality of life.

Accelerated PBI is logistically simpler and a more practical method for breast-conserving therapy, but it has to be demonstrated in randomized phase-III trials that it is at least equivalent to WBRT before its routine use.

MRSI has the potential to provide metabolic evidence of tumor activity that may be an important guide for therapeutic decisions. The treatment planning process and treatment planning systems should therefore have the ability to incorporate both metabolic and anatomic data in order to determine appropriate target volumes. Many problems need to be addressed and much work needs to be done in order to determine the optimal way to incorporate indices of metabolic activity, especially in light of newer treatment techniques such as IMRT; however, it is the present author’s belief that strong consideration should be given to the incorporation of functional imaging into the treatment process for focal or boost treatments for brain and prostate tumors. Given the discrepancies that have been found between MRI and MRSI determinants of target volumes, the results of controlled dose escalation studies for malignant tumors of the brain that have used MRI-derived target volumes should also be reevaluated given the possibility that these volumes may have been suboptimally defined.

Target volume definition is an interactive process. Based on radiological (and biological) imaging, the radiation oncologist has to outline the GTV, CTV, ITV, and PTV and BTV. In this process, a lot of medical and technological aspects have to be considered. The criteria for GTV, CTV, etc. definition are often not exactly standardised, and this leads, in many cases to variability between clinicians; however, exactly defined imaging criteria, imaging with high sensitivity and specificity for tumour tissue and special training could lead to a higher consensus in target volume delineation and, consequently, to lower differences between clinicians. It must be emphasised, however, that further verification studies and cost-benefit analyses are needed before biological target definition can become a stably integrated part of target volume definition.

The ICRU report 50 from 1993 and the ICRU report 62 from 1999 defining the anatomically based terms CTV, GTV and PTV must still be considered as the gold standard in radiation treatment planning; however, further advances in technology concerning signal resolution and development of new tracers with higher sensitivity and specificity will induce a shift of paradigms away from the anatomically based target volume definition towards biologically based treatment strategies. New concept and treatment strategies should be defined based on these new investigation methods, and the standards in radiation treatment planning — in a continuous, evolutionary process — will have to integrate new imaging methods in an attempt to finally achieve the ultimate goal of cancer cure.

Several biological models have been developed. Although these models give a correct description of the main characteristics of the radiation response, great caution has to be taken if these models are to be applied to patients.

While the linear-quadratic model provides a good description of experimental settings, a larger uncertainty is involved in the prediction of iso-effects for clinical applications. The more advanced NTCP and TCP models should only be applied for relative, rather than absolute, predictions of effect probabilities. When using relative values, the uncertainty of the predictions should be considered to decide whether a detected difference is really significant. As TCP/NTCP models are currently not completely validated, integration of these models into the cost function of the dose optimisation algorithm is not warranted. Whether it is possible to arrive at fully biologically optimised treatment plans for photon therapy has to be investigated by further research.

In this context, the clinical application of heavy charged particles plays an exceptional role as biological optimisation is routinely performed and an adequate RBE model is an essential prerequisite. The applied RBE model may still contain some degree of uncertainty which has to be considered carefully at treatment plan assessment and dose prescription.

Stereotactic radiation treatment of extracranial targets shows promising initial results. The techniques are getting increasingly more specialized, especially in the treatment of small lung tumors; however, many questions remain unanswered. More experimental work and clinical trials are underway which should answer these question and should strengthen this promising approach.

MRSI has the potential to provide metabolic evidence of tumor activity that may be an important guide for therapeutic decisions. The treatment planning process and treatment planning systems should therefore have the ability to incorporate both metabolic and anatomic data in order to determine appropriate target volumes. Many problems need to be addressed and much work needs to be done in order to determine the optimal way to incorporate indices of metabolic activity, especially in light of newer treatment techniques such as IMRT; however, it is the present author’s belief that strong consideration should be given to the incorporation of functional imaging into the treatment process for focal or boost treatments for brain and prostate tumors. Given the discrepancies that have been found between MRI and MRSI determinants of target volumes, the results of controlled dose escalation studies for malignant tumors of the brain that have used MRI-derived target volumes should also be reevaluated given the possibility that these volumes may have been suboptimally defined.