Radiother Oncol 2015 Aug 04
Radiation-induced dose-dependent changes of the spleen following postoperative chemoradiotherapy for gastric cancer.
Abstract
Background and purpose
Abdominal (chemo-)radiotherapy is associated with dose-limiting toxicity of various normal structures. The purpose of this retrospective study was to investigate radiation-induced changes of the spleen and their clinical consequences.
Patients and methods
In gastric cancer patients treated with postoperative chemoradiotherapy, the spleen size and its functions were assessed at follow-up by spleen volume on CT-scan, serum leucocytes/thrombocytes, and the occurrence of infectious events consisting of pneumonia and fatal sepsis. To evaluate the effect of radiation dose, mixed effects and Cox regression models were used.
Results
Forty-six out of 90 consecutive patients treated from 2006 to 2011 were evaluable. All patients received 45 Gy in 25 fractions with concurrent capecitabine (n=8), and capecitabine/cisplatin (n=38). Median Dmean to the spleen was 40 Gy (range 32-46). Mean relative spleen volume reduced to 37% (95% CI 32-42%) at 4-year follow-up, which was most strongly associated to the V44 (p<0.001). Median follow-up time was 67 (95% CI 57-78) months. Eleven patients had 13 pneumonias and 3 fatal sepsis. No association with dosimetric parameters was observed.
Conclusions
In postoperative chemoradiotherapy for gastric cancer, the spleen received a high radiation dose. This resulted in a progressive, radiation dose-dependent reduction of spleen volume. Pneumonia and fatal sepsis occurred frequently, possibly as a result of functional hyposplenia.
Related Questions
When treating pancreatic body/tail lesions that result in significant dose spread to the spleen, what is your threshold to offer pneumococcal, hemophilus influenza, and meningococcal vaccines?
A really great question, and one that we don’t necessarily have a lot of data for guidance. There are some guidelines out there, though, that I think can be helpful to consider. The first is the recent guideline from ASCO on the vaccination of adults with cancer (Kamboj et al., PMID 38498792). In li...
When do you recommend patients get vaccinations with respect to their RT course?
I agree with @Dr. First Last's reply, and find that some patients are under the impression they are immunocompromised during radiation therapy and thus should avoid vaccines, when in fact the opposite is true. The skepticism behind the science of vaccination also can lead to avoidance, and so I try ...