Standard- versus individuell geplantes Bestrahlungsfeld bei Radiotherapie infradiaphragmaler Lymphknotenstationen

Abstract

Our data show, that the customary fields for infradiaphragmatic lymphatic nodes have so far not been able to enclose all retroperitoneal and pelvic lymph nodes with certainty.

Optimized Conformal Paraaortic Lymph Node Irradiation is not Associated with Enhanced Renal Toxicity

“…As previously reported [19], prophylactic nodal irradiation planned using the contours of bony structures excludes a significant number of potentially involved PLNs (~10%). According to that study, the risk of nonencompassed lymph nodes can be reduced to < 3% by patient-specific and individually defined planning target volume (PTV) delineation along the aorta and the vena cava.…”

“…Normal-tissue complication probabilities (NTCPs) of individually planned PLN four-box irradiation with enlarged safety margins were shown to statistically be the same as for standard techniques. Inclusion of ~97% PLNs when using our previously described technique [19] -instead of ~90% following standard irradiation -might lead enhanced tumor control probability (TCP) to be expected. However, the question to what extent NTCP estimates reliably predict radiation-induced nephropathy remains a matter of discussion.…”

Variation in "Supraclavicular" Lymph Node Depth is Partly Determined by Treatment Position

“…Therefore, an individual target volume delineation by computed tomography seems to be more adequate with regard to the "supraclavicular" nodes than a standardized portal prescription [2,6,[17][18][19]. This had already been advised for other lymphatic regions [10,11,20]. Furthermore, immobilization of the patient is crucial to reassure the daily accuracy in treatment delivery to mobile target volumes like the "supraclavicular" region ( Figure 4).…”

“…The shortcomings of standardized field arrangements for treatment of lymphatic regions have previously been discussed in this journal, like for inguinal radiotherapy in vulvar carcinoma [1], for paraaortal treatment in seminoma [20], and for infradiaphragmatic irradiation in non Hodgkin lymphoma [10]. Similarly, we wanted to record the average lymph node depth in the supraclavicular fossa.…”

Langzeittumorkontrolle und Fertilität nach paraaortal limitierter Radiotherapie des Seminoms im Stadium I

“…Bei standardisierten Feldgrenzen, die sich an knöchernen Konturen orientieren, können bis zu 10% der relevanten Lymphknotenstrukturen außerhalb des Bestrahlungsfeldes liegen [17]. Zimmermann et al [30] demonstrierten die Vorteile einer MRT-geplanten Paraaortalbestrahlung zur sicheren Erfassung des gesamten Verlaufs der großen Gefäße und des Nierenhilus bei gleichzeitig optimierter Schonung von Nierenparenchym.…”