J.M. Slater

Surgical and radiation therapy management of recurrent anal melanoma

BACKGROUND Melanoma of the anorectal mucosa is a rare but highly aggressive tumor. Its presenting symptoms are frequently confused with hemorrhoids, thereby causing a delay in diagnosis. Anorectal melanoma carries with it a very poor prognosis. There is a paucity of data investigating management options for anorectal melanoma, and even fewer data reporting recurrent or refractory cases. CASE PRESENTATION This case documents a 41-year-old female with a long history of hemorrhoids presenting with anorectal discharge. She was incidentally found have anorectal melanoma following surgical resection. Systemic diagnostic work-up demonstrated PET-avid lymphadenopathy in her right groin. She underwent right groin dissection. However, seven months later she recurred in her right groin and a new recurrent mass was found in her pelvis. She underwent a second groin dissection and resection of the pelvic recurrence. This was followed by a course of hypofractionated radiation therapy then systemic immunotherapy. DISCUSSION Surgery has been the mainstay of treatment. However, the extent of surgery has been the topic of investigation. Historically, radical resections have been performed but they result in high rates of post-operative morbidity. Newer studies have compared radical resection with wide local excisions and found comparable outcomes. Anorectal melanoma is frequently a systemic disease. The ideal systemic therapy regimen has not yet been determined but numerous studies show a benefit to multi-agent treatments. Radiation therapy is typically given in the post-operative or palliative setting. CONCLUSIONS Anorectal mucosal melanoma is a very rare but aggressive disease with a poor prognosis. The overall treatment goal should strive to optimize quality of life and tumor control while minimizing treatment-related morbidities.

A Clinical Interactive Technique for MR-CT Image Registration for Target Delineation of Intracranial Tumors

Replacement of current CT-based, three-dimensional (3D) treatment planning systems by newer versions capable of automated multi-modality image registration may be economically prohibitive for most radiation oncology clinics. We present a low-cost technique for MR-CT image registration on a “first generation” CT-based, 3D treatment planning system for intracranial tumors. The technique begins with fabrication of a standard treatment mask. A second truncated mask, the “minimask,” is then made, using the standard mask as a mold. Two orthogonal leveling vials glued onto the minimask detect angular deviations in pitch and roll. Preservation of yaw is verified by referencing a line marked according to the CT laser on the craniocaudal axis. The treatment mask immobilizes the patients head for CT. The minimask reproduces this CT-based angular treatment position, which is then maintained by taping the appropriately positioned head to the MR head coil for MR scanning. All CT and MR images, in DICOM 3.0 format, are entered into the treatment planning system via a computer network. Interactive registration of MR to CT images is controlled by real-time visual feedback on the computer monitor. Translational misalignments at the target are eliminated or minimized by iterative use of qualitative visual inspection. In this study, rotational errors were measured in a retrospective series of 20 consecutive patients who had undergone CT-MR image registration using this technique. Anatomic structures defined the three CT orthogonal axes from which angular errors on MR image were measured. Translational errors at the target isocenter were within pixel size, as judged by visual inspection. Clinical setup using the minimask resulted in overall average angular deviation of 3°±2° (mean ± SD) and translational deviation within the edges of the target volume of typically less than 2 mm. The accuracy of this registration technique for target delineation of intracranial tumors is compatible with practice guidelines. This method, then, provides a cost-effective means to register MR and CT images for target delineation of intracranial tumors.

The prognostic value of percentage of positive biopsy cores, percentage of cancer volume, and maximum involvement of biopsy cores in prostate cancer patients receiving proton and photon beam therapy.

The purpose of the study is to compare the prognostic value of percentage of positive biopsy cores (PPBC), percentage of cancer volume (PCV), and maximum involvement of biopsy cores (MIBC) as a prognostic factor in low- and intermediate-risk patients with clinically localized prostate cancer who received proton or photon beam therapy. Four hundred and fifty-nine patients with clinically localized prostate carcinoma who were treated with proton or photon beam therapy at Loma Linda University Medical Center were used for this analysis. Patients were treated with a median dose of 74.0 Gy (range 70.2–79.2) proton or combined proton/photon beam radiotherapy. Pathology reports were reviewed and PPBC, PCV, and MIBC were recorded. Analysis of biochemical no evidence of disease (bNED) outcome was assessed using Kaplan-Meier analyses. Cox regression multivariate analyses were performed to assess the impact of the biopsy factors on survival. Results: 285, 291, and 291 patients had biopsy information available for analysis, respectively. Survival analysis showed that a higher PPBC, PCV, and MIBC were each individually associated with an increased risk of biochemical failure on univariate analysis (p < 0.01). Only PPBC and PCV were associated with an increased risk of biochemical failure on multivariate analysis, adjusting for age, NCCN risk group, and dose (p < 0.01). When isolating the intermediate-risk group, only PPBC and PCV were statistically significant on multivariate analysis. Multivariate analysis of the intermediate-risk group comparing PPBC and PCV showed that PPBC was not a significant predictor of biochemical failure, while PCV was a significant predictor of biochemical failure (p = 0.37 and p = 0.03, respectively). Conclusion: PPBC and PCV can potentially be used for additional risk stratification of intermediate-risk patients with PCV potentially being the most clinically relevant predictor bNED survival. MIBC was not found to have utility in the prognosis of low- and intermediate-risk patients.

Percentage of Positive Biopsy Cores Predicts Presence of a Dominant Lesion on MRI in Patients with Intermediate Risk Prostate Cancer

Risk strati ication for prostate cancer utilizes well-established parameters of T stage, Gleason score, and prostate-speci ic antigen (PSA) level [1]. More recently, additional factors such as the percentage of positive biopsy cores (PPCs), percentage of cancer volume (PCV), and maximum involvement of biopsy cores (MIBC) have been shown to have prognostic value, particularly in National Comprehensive Cancer Network (NCCN) intermediate risk patients [2-5]. Magnetic resonance imaging (MRI) of the prostate has been shown to have prognostic signi icance [6-9] and has been shown to correlate with various prognostic factors seen on biopsy [10-13]. These studies have evaluated prognostic factors and MRI indings of extracapsular extension (ECE) and Abstract

Stratifying risk of prostate cancer recurrence following external beam radiation therapy: Comparing prostate MRI with prostate biopsy pathology.

Background: In patients with clinically localized prostate cancer receiving external beam radiation therapy, studies have shown information from prostate biopsy cores can be predictive of clinical outcomes. Recent work from our institution compared several biopsy findings in low- and intermediate-risk patients and found a subset of patients who were more likely to fail treatment. This indicates patients in these groups may benefit from further risk stratification prior to initiation of therapy. Furthermore, findings on pre-treatment prostate MRI independently predict PSA relapse after external beam radiation therapy. Comparing MRI and pathological data may help to accurately further risk stratify patients. Our purpose is to determine if there is a correlation between the poor prognostic factors demonstrated on prostate biopsy cores and selected findings on prostate MRI. Methods: Intermediate risk prostate cancer patients with 1.5 and 3.0 Tesla MRI scans of the prostate performed from 2007-2011 were selected for a retrospective cohort study. Cases were reviewed by two body-trained radiologists who were blinded to clinical patient information. Reader consensus was obtained at the time of reading regarding presence of extracapsular extension, seminal vesicle invasion, and disease in each sextant by T2 and ADC imaging, including a dominant nodule. Results were analyzed for correlation between these findings on MRI and compared with results of prostate biopsy cores, including maximum involvement of any biopsy core (MIBC), percentage of cancer volume (PCV) and percent positive biopsy cores (PPBC). Results: The absolute presence of a dominant nodule on MRI was statistically significantly correlated with elevated PCV and PPBC applying the t-test for equality of means, with p-values of 0.019 and 0.006 respectively. PSA, Gleason score, and MIBC were not found to be correlated with dominant nodule on MRI. Conclusions: There is a strong positive correlation between MRI findings of a dominant nodule and prognostic biopsy findings of elevated PPBC and PCV.

Palliative radiation therapy for primary gastric melanoma

INTRODUCTION Primary gastric melanoma is an exceedingly rare cause of upper gastrointestinal bleeding (GI bleeding). Prior reports of primary gastric melanoma have mostly been treated with surgery with utilization of radiation therapy being unreported. Radiation therapy has been used to palliate bleeding of other cancers including lung, bladder, cervix, and more recently primary gastric cancers. CASE PRESENTATION This case documents an 87-year-old male who presented with fatigue and melena, and was found to have severe anemia. Endoscopy with biopsy revealed an isolated focus of melanoma. After discharge, he presented two days later and was found to have continued bleeding. Because he was deemed a poor surgical candidate he elected to undergo palliative radiation therapy for bleeding control. DISCUSSION The diagnosis of primary verses metastatic melanoma is a topic of debate. Case reports of patients with no known extra-gastric primary have undergone surgical treatment with varying outcomes. Patients with metastatic gastric melanoma have relied on chemotherapy and radiation in addition to surgery, with radiation being used in the palliative setting. The use of radiation to control bleeding in other cancers including primary gastric adenocarcinoma has been previously studied. This case documents the utilization of radiation therapy in bleeding due to primary gastric melanoma. CONCLUSIONS Radiation therapy can provide adequate bleeding palliation in patients with primary gastric melanoma.