Matthew S. Katz

Predictors of biochemical outcome with salvage conformal radiotherapy after radical prostatectomy for prostate cancer.

PURPOSEnTo identify predictors of biochemical outcome following radiotherapy in patients with a rising prostate-specific antigen (PSA) after radical prostatectomy for prostate cancer.nnnPATIENTS AND METHODSnOne hundred fifteen patients with a rising PSA after radical prostatectomy received salvage three-dimensional conformal radiotherapy (3D-CRT) alone or with neoadjuvant androgen deprivation. Tumor-related and treatment-related factors were evaluated to identify predictors of subsequent PSA failure.nnnRESULTSnThe median follow-up time after 3D-CRT was 42 months. The 4-year actuarial PSA relapse-free survival, distant metastasis-free survival, and overall survival rates were 46%, 83%, and 95%, respectively. Multivariate analysis, which was limited to 70 patients receiving radiation without androgen deprivation therapy, showed that negative/close margins (P =.03), absence of extracapsular extension (P <.01), and presence of seminal vesicle invasion (P <.01) were independent predictors of PSA relapse after radiotherapy. Neoadjuvant androgen deprivation did not improve the 4-year PSA relapse-free survival in patients with positive margins, extracapsular extension, and no seminal vesicle invasion (P =.24). However, neoadjuvant androgen deprivation did improve PSA relapse-free survival when one or more of these variables were absent (P =.03).nnnCONCLUSIONSnSalvage 3D-CRT can provide biochemical control in selected patients with a rising PSA after radical prostatectomy. Among patients with positive margins and no poor prognostic features, 77% achieved PSA control after salvage 3D-CRT. Salvage neoadjuvant androgen deprivation therapy may improve short-term biochemical control, but it requires further study.

Development of a semi-automatic alignment tool for accelerated localization of the prostate

PURPOSEnDelivering high dose to prostate with external beam radiation has been shown to improve local tumor control. However, it has to be carefully performed to avoid partial target miss and delivering excessive dose to surrounding normal tissues. One way to achieve safe dose escalation is to precisely localize prostate immediately before daily treatment. Therefore, the radiation can be accurately delivered to the target. Once the prostate position is determined with high confidence, planning target volume (PTV) safety margin might be reduced for further reduction of rectal toxicity. A rapid computed tomography (CT)-based online prostate localization method is presented for this purpose.nnnMETHODS AND MATERIALSnImmediately before each treatment session, the patient is immobilized and undergoes a CT scan in the treatment position using a CT scanner situated in the treatment room. At the CT console, posterior, anterior, left, and right extents of the prostate are manually identified on each axial slice. The translational prostate displacements relative to the planned position are estimated by simultaneously fitting these identified extents from this CT scan to a template created from the finely sliced planning CT scan. A total of 106 serial CT scans from 8 prostate cancer patients were performed immediately before treatments and used to retrospectively evaluate the precision of this daily prostate targeting method. The three-dimensional displacement of the prostate with respect to its planned position was estimated.nnnRESULTSnFive axial slices from each treatment CT scan were sufficient to produce a reliable correction when compared with prostate center of gravity (CoG) displacements calculated from physician-drawn contours. The differences (mean +/- SD) between these two correction schemes in the right-left (R/L), posterior-anterior (P/A), and superior-inferior (S/I) directions are 0.0 +/- 0.4 mm, 0.0 +/- 0.7 mm, and -0.4 +/- 1.9 mm, respectively. With daily CT extent-fitting correction, 97% of the scans showed that the entire posterior prostate gland was covered by PTV given a margin of 6 mm at the rectum-prostate interface and 10 mm elsewhere. In comparison, only 74% and 65% could be achieved by the corrections based on daily and weekly bony matching on portal images, respectively.nnnCONCLUSIONSnResults show that daily CT extent fitting provides a precise correction of prostate position in terms of CoG. Identifying prostate extents on five axial CT slices at the CT console is less time-consuming compared with daily contouring of the prostate on many slices. Taking advantage of the prostate curvature in the longitudinal direction, this method also eliminates the necessity of identifying prostate base and apex. Therefore, it is clinically feasible and should provide an accelerated localization of the prostate immediately before daily treatment.

Tumor Motion Control in the Treatment of Non Small Cell Lung Cancer

Tumor motion due to respiration during radiation therapy for non-small cell lung cancer is a significant problem. This article reports on two techniques used to control tumor motion: respiratory gating and the deep inspiration breath hold technique. This technique was implemented in 40 patients without significant difficulties and there are encouraging clinical outcomes.

Statin use may increase the pathologic complete response rate after neoadjuvant chemoradiation for rectal cancer

3568 Background: Laboratory data suggest that HMG-CoA reductase inhibitors, or statins, may have antitumor activity in colorectal cancer. We explored whether or not statins might enhance the efficacy of neoadjuvant chemoradiation in rectal cancer.nnnMETHODSnBetween 1996-2001, 358 patients with clinically resectable, nonmetastatic rectal cancer underwent surgery at Memorial Sloan-Kettering Cancer Center after neoadjuvant chemoradiation for either locally advanced tumors, or for low-lying tumors that would require abdominoperineal resection. We excluded 9 patients for RT dose < 45 Gy or if statin use was unknown, leaving 349 evaluable patients. Median RT dose was 50.4 Gy (range: 45-55.8 Gy), and 308 (88%) received 5-FU based chemotherapy. Medication use, comorbid illnesses, clinical stage by DRE and ultrasound, and type of chemotherapy were analyzed for associations with pathologic complete response (pCR), defined as no microscopic evidence of tumor. Fishers exact test was used for categorical variables, Mantel-Haenszel test for ordered categorical variables, and logistic regression for numeric variables and multivariate analysis.nnnRESULTSnThirty-three patients (9%) used a statin, with no differences in clinical stage by DRE or ultrasound compared to the other 324 patients. At the time of surgery, 23 of the 324 (7%) non-statin patients were found to have metastatic disease, compared to 0% for statin patients. The pCR rate with and without statin use was 30% versus 17% (p=0.10). Variables significant univariately at the p=0.15 level were entered into a multivariate model. The odds ratio for statin use on pCR was 2.1 (95% CI: 0.93, 4.9, p-value=0.07) after adjusting for clinical stage and type of chemotherapy.nnnCONCLUSIONSnStatin use appears to be weakly associated with an improved pCR rate after neoadjuvant chemoradiation for rectal cancer. The non-randomized nature of this comparison and the low prevalence of statin use limit the power of this observation. However, the unusually high incidence of pCR suggests that the use of statins in rectal cancer may warrant further study. [Table: see text].