The Promise of Magnetic Resonance Imaging in Radiation Oncology Practice in the Management of Brain, Prostate, and GI Malignancies.

Magnetic resonance imaging (MRI) has a key role to play at multiple steps of the radiotherapy (RT) treatment planning and delivery process. Development of high-precision RT techniques such as intensity-modulated RT, stereotactic ablative RT, and particle beam therapy has enabled oncologists to escalate RT dose to the target while restricting doses to organs at risk (OAR). MRI plays a critical role in target volume delineation in various disease sites, thus ensuring that these high-precision techniques can be safely implemented. Accurate identification of gross disease has also enabled selective dose escalation as a means to widen the therapeutic index. Morphological and functional MRI sequences have also facilitated an understanding of temporal changes in target volumes and OAR during a course of RT, allowing for midtreatment volumetric and biological adaptation. The latest advancement in linear accelerator technology has led to the incorporation of an MRI scanner in the treatment unit. MRI-guided RT provides the opportunity for MRI-only workflow along with online adaptation for either target or OAR or both. MRI plays a key role in post-treatment response evaluation and is an important tool for guiding decision making. In this review, we briefly discuss the RT-related applications of MRI in the management of brain, prostate, and GI malignancies.

Validation and applicability of para-aortic lymph nodal contouring atlas in cervical cancer.

BACKGROUND AND PURPOSE: CTV delineation guidelines for the para-aortic nodal region for patients with cervical cancer have been proposed (Keenan et al., 2018). The purpose of this study was to validate these guidelines with the use of CT datasets of cervical cancer patients with macroscopic PALN treated with definitive (chemo)radiation (CTRT) at our center. MATERIALS AND METHODS: Planning CT datasets of 71 cervical cancer patients with gross PA nodal disease treated with EFRT were used. Two hundred and two PALN were identified based on size and morphology on diagnostic CECT, PET CT, or histologically proven PALN. LN regions were divided into upper, middle, and lower and based on their relation to the aorta and IVC. Macroscopic PALN were contoured, and the CTV for PALN irradiation was generated based on the proposed guidelines on ECLIPSE (Version 13.5). The centre of mass (COMN) was calculated for each gross PALN. The evaluation was done to review the presence of COMN in relation to the CTV PALN. RESULTS: The most common location of PALN was Left para-aortic (105 LN-52%), Aortocaval (55 LN-27.2%), and Precaval (14 LN-6.9%). Lower PALN were the commonest (104 LN-51.5%). Ninety-three were middle PALN (46%), and 5 were upper PALN (2.5%). After excluding upper PALN, COMN for 11 PALN (5.5%) were outside the CTV while 20 were junctional. CONCLUSION: Our study shows that more than 95% of PALN in this patient cohort were covered using these guidelines with the addition of an extra 5 mm margin laterally on the left.

Standard maintenance therapy versus local consolidative radiation therapy and standard maintenance therapy in 1-5 sites of oligometastatic non-small cell lung cancer: a study protocol of phase III randomised controlled trial.

INTRODUCTION: Two-phase II randomised studies have shown a significant benefit of local consolidation therapy in oligometastatic non-small cell lung cancer (NSCLC). This phase III randomised controlled trial (RCT) will evaluate the efficacy of local consolidation radiation therapy (RT) in oligometastases (OM) NSCLC after completion of initial systemic therapy. METHODS AND ANALYSIS: This is a single-centre phase III RCT of OM NSCLC patients. One hundred and ninety patients will undergo 1:1 randomisation to either standard maintenance therapy (control arm) or local consolidation RT and standard maintenance therapy (experimental arm). Patients will be stratified into the number of OM sites (1-2 vs 3-5), nodal metastases (N0-N1 vs N2-N3) and presence or absence of brain metastases. Stereotactic body radiation therapy to all the oligometastatic sites and definitive RT to primary disease will be given in the experimental arm. The primary endpoint is overall survival and secondary endpoints include progression-free survival, local control of OM sites, new distant metastases free survival, objective response rate, toxicity and quality of life. Translation endpoint include circulating tumour cells and radiomics using texture analysis. ETHICS AND DISSEMINATION: All patients will be provided with a written informed consent form which needs to be signed before randomisation. The study is approved by the institutional ethics committee-II (project number 3445) and registered with Clinical Trials Registry-India, dated 21 April 2020. TRIAL REGISTRATION NUMBER: CTRI/2020/04/024761; Pre-Results.

Locoregional recurrence after cystectomy in muscle invasive bladder cancer: Implications for adjuvant radiotherapy.

PURPOSE: We report the patterns of locoregional recurrence (LRR) in muscle invasive bladder cancer (MIBC), and propose a risk stratification to predict LRR for optimizing the indication for adjuvant radiotherapy. MATERIALS AND METHODS: The study included patients of urothelial MIBC who underwent radical cystectomy with standard perioperative chemotherapy between 2013 and 2019. Recurrences were classified into local and/or cystectomy bed, regional, systemic, or mixed. For risk stratification modelling, T stage (T2, T3, T4), N stage (N0, N1/2, N3) and lymphovascular invasion (LVI positive or negative) were given differential weightage for each patient. The cohort was divided into low risk (LR), intermediate risk (IR) and high risk (HR) groups based on the cumulative score. RESULTS: Of the 317 patients screened, 188 were eligible for the study. Seventy patients (37.2%) received neoadjuvant chemotherapy (NACT) while 128 patients (68.1%) had T3/4 disease and 66 patients (35.1%) had N+ disease. Of the 55 patients (29%) who had a recurrence, 31 (16%) patients had a component of LRR (4% cystectomy bed, 11.5% regional 0.5% locoregional). The median time to LRR was 8.2 (IQR 3.3-18.8) months. The LR, IR and HR groups for LRR based on T, N and LVI had a cumulative incidence of 7.1%, 21.6%, and 35% LRR, respectively. The HR group was defined as T3, N3, LVI positive; T4 N1/2, LVI positive; and T4, N3, any LVI. The odds ratio for LRR was 3.37 (95% CI 1.16-9.73, P = 0.02) and 5.27 (95% CI 1.87-14.84, P = 0.002) for IR and HR respectively, with LR as reference. CONCLUSION: LRR is a significant problem post radical cystectomy with a cumulative incidence of 35% in the HR group. The proposed risk stratification model in our study can guide in tailoring adjuvant radiotherapy in MIBC.

Distant Skin Metastases from Carcinoma Buccal Mucosa: A Rare Presentation.

Cancer of the oral cavity makes up approximately 30% of all head and neck region tumors. Skin metastasis is rare with an incidence ranging between 0.7% and 2.4%. Skin metastasis usually occurs in the neck, scalp, and over the skin near the primary site. We report a patient with carcinoma left buccal mucosa who presented with distant skin metastases to the right side chest wall.

Primary adenocarcinoma of ureter: A rare histopathological variant.

Primary carcinoma of ureter is an uncommon malignancy. Of which, mostly are transitional cell carcinomas followed by squamous cell carcinomas and adenocarcinomas being the rarest histopathology encountered. We report a case of adenocarcinoma ureter in a middle-aged male along with its clinical scenario. A 62-year-old male, presented with complaints of lower urinary tract symptoms. Computerized tomography urogram showed a soft tissue lesion at the right ureterovesical junction. Cystoscopic biopsy reported villous adenoma. Diethylene triamine pentaacetic acid scan reported nonfunctioning right kidney. He underwent laparoscopic right nephroureterectomy, and histopathology reported adenocarcinoma of the right lower third of ureter, with positive distal and close radial margins. The patient received external beam radiation to the postoperative bed and lymph nodes, and he is disease-free till date.

Chemoradiation for organ preservation in the treatment of muscle invasive bladder cancer: Our Institutional Experience.

AIM: To assess outcome of chemoradiotherapy for organ preservation in muscle invasive bladder cancer. MATERIAL AND METHODS: 41 patients treated between January 2010 to January 2015 were evaluated in the present study. All patients T staged ranging from cT2-T4a and had undergone maximal transurethral resection of bladder tumour (TURBT). After maximum bladder tumour resection patients were treated with Radiotherapy with or without concurrent chemotherapy. 8 weeks after completion of treatment response was assessed by check cystoscopy, urine cytology and CECT scan Abdomen. Data regarding the toxicity profile, initial complete response rates at 3 months, occurrence of loco regional or distant failure and survival was recorded. RESULTS: Age ranged between 45- 84 years, (mean age 65.44). Radiotherapy dose planned ranged from 60 Gy/30fr to 70.3 Gy/37 fractions to primary target and 59.2 Gy/37fractions to the nodal disease. PTV volume ranged from 69-548.9 cc. 23 patients received concurrent chemotherapy weekly. 11 patients have cystitis (5 Gr 1, 4 Gr II and 2 Gr III). 5 patients have myelosuppression. 10 patients have acute gastrointestinal toxicity (5 Gr-I, 4 Gr-II, 1 Gr-III). At the time of analysis follow up ranged from 3-42 months (median follow 1 year).The DFS at 42 months was 54%. Out of 39 patients 3 were lost to follow up (2 in partial bladder group and 1 in whole bladder group). Out of 36 patients 24 (66.6%) are disease free, 4 (11.1%) patients had recurrence for which 2 underwent salvage cystectomy whereas 2 patients received palliative chemotherapy. Five patients developed distant metastases (4 bone and 1 brain metastasis). CONCLUSION: Bladder-preservation therapy for muscle-invasive bladder cancer is a valid substitute in selected cases with long-term efficacy similar to radical cystectomy, with the additional advantage of preserving excellent bladder function in the majority of long-term survivors.