Swarupa Mitra

Synchronous malignant vagal paraganglioma with contralateral carotid body paraganglioma treated by radiation therapy

Paragangliomas are rare tumors and very few cases of malignant vagal paraganglioma with synchronous carotid body paraganglioma have been reported. We report a case of a 20-year old male who presented with slow growing bilateral neck masses of eight years duration. He had symptoms of dysphagia to solids, occasional mouth breathing and hoarseness of voice. Fine needle aspiration cytology (FNAC) performed where he lived showed a sinus histiocytosis and he was administered anti-tubercular treatment for six months without any improvement in his symptoms. His physical examination revealed pulsatile, soft to firm, non-tender swellings over the anterolateral neck confined to the upper-mid jugulo-diagastric region on both sides. Direct laryngoscopy examination revealed a bulge on the posterior pharyngeal wall and another over the right lateral pharyngeal wall. Magnetic resonance imaging (MRI), 99mTc-labeled octreotide scan and angiography diagnosed the swellings as carotid body paraganglioma, stage III on the right side with left-sided vagal malignant paraganglioma. Surgery was ruled out as a high morbidity with additional risk to life was expected due to the highly vascular nature of the tumor. The patient was treated with radiation therapy by image guided radiation to a dose of 5040cGy in 28 fractions. At a follow-up at 16 months, the tumors have regressed bilaterally and the patient can take solids with ease.

Is volumetric modulated arc therapy (RapidArc) better than intensity modulated radiotherapy for gynecological malignancies? A dosimetric comparison

AIMSnEvaluation of the dosimetric advantage, if any, of RapidArc (double arc and triple arc [DA and TA]) over standard fixed field intensity-modulated radiation therapy (IMRT) in gynecologic malignancies.nnnMATERIALS AND METHODSnA total of 20 cases of gynecologic malignancies were included. Static IMRT sliding window, single arc (SA), DA and TA plans were generated with eclipse planning system. The prescribed dose was 50.4 Gy/28# to the planning target volumes.nnnRESULTSnIMRT provided target coverage equivalent to DA and inferior to TA (D95% [in Gy]--49.94, 49.58, 49.96, 50.17 for IMRT, SA, DA and TA respectively--all observations in the same sequence). Conformity index 90 (CI 90 (0.964, 0.927, 0.918, 0.822) and homogeneity index (0.0683, 0.119, 0.098, 0.097) of IMRT were superior. TA was superior to other arcs in all parameters except CI 90 (P=0.805) and bladder dose (lower in DA). Rectal, bladder and bowel sparing was best achieved with IMRT followed by TA; bilateral femur dose was lower in arcs. The total monitor units and treatment time of arcs were significantly lower than IMRT, reduced by a factor of 2.41-2.59 and 3.2-3.5 respectively (All P values significant).nnnCONCLUSIONnIMRT provided better overall plan for gynecologic malignancies with lower organs at risk dose and target coverage equivalent to DA and TA. Treatment delivery efficiency was higher with RapidArc. The TA plan is dosimetrically superior to DA, but the gain is small. The decision whether or not to add a third arc for a small gain should be individualized.

Pulmonary metastasis from renal synovial sarcoma treated by stereotactic body radiotherapy: A case report and review of the literature

Primary synovial sarcoma of kidney is an uncommon neoplasm, metastasizing most commonly to lung. Surgery and/or palliative chemotherapy for pulmonary metastases is commonly used to improve tumor control and survival. Stereotactic body radiotherapy (SBRT) is a relatively new approach to treat pulmonary metastasis, encouraged by the results of cranial and spinal stereotactic radiosurgery. The local control and toxicity profile of patients with pulmonary metastasis treated with SBRT are comparable to pulmonary metastatectomy. Furthermore, with advancement of imaging techniques, immobilization techniques, tumor-tracking techniques, and treatment planning and delivery system, SBRT can now be alternatively employed for the treatment of pulmonary metastasis as a comparable substitute to surgical resection.

Prospective study of neoadjuvant chemoradiotherapy using intensity-modulated radiotherapy and 5 fluorouracil for locally advanced rectal cancer – toxicities and response assessment

Aims and objectives The past 2 decades witnessed the strengthening of evidence favoring the role of neoadjuvant chemoradiation (CHRT) in the treatment of locally advanced rectal cancer. The study aims to evaluate the response and acute toxicities to neoadjuvant CHRT using intensity-modulated radiotherapy (IMRT) in the treatment of rectal cancer. Predictive factors to achieve pathological complete response (pCR) were analyzed, as a secondary endpoint. Materials and methods All consecutive patients who underwent IMRT as part of neoadjuvant CHRT in the treatment of rectal cancer between August 2014 and December 2016 at a tertiary cancer care center were accrued for the study. The cohort underwent CHRT with IMRT technique at a dose of 50.4 Gy in 28 fractions concurrent with continuous infusion of 5 fluorouracil during the first and the last 4 days of CHRT. Surgery was performed 6 weeks later and the pathological response to CHRT was noted. Results Forty-three subjects were accrued for the study. Radiation dermatitis and diarrhea were the only observed grade ≥3 acute toxicities. Sphincter preservation rate (SPR) was 43.3%. pCR was observed in 32.6%. Univariate and multivariate logistic regression showed that carcinoembryonic antigen was the only independent predictive factor to achieve pCR. Conclusion IMRT as part of neoadjuvant CHRT in the treatment of locally advanced rectal cancer is well tolerated and gives comparable results with respect to earlier studies in terms of pathological response and SPR. Further randomized controlled studies are needed to firmly state that IMRT is superior to 3-dimensional conformal radiotherapy.

Vulvar carcinoma: dilemma, debates, and decisions

Vulvar carcinoma is a rare and aggressive gynecological malignancy. It affects elderly females, with the mean age at diagnosis being 55–60 years. Regional metastasis to inguinal lymph nodes is common. There is a high incidence of pelvic node involvement, especially in those with pathologically positive inguinal nodes. Surgery appears to be the only curative treatment option in the early stages of the disease. But in most patients, surgery is associated with considerable morbidities and psychosexual issues. Hence, in the quest for a less morbid form of treatment, multimodality approaches with various combinations of surgery, chemotherapy, and radiation therapy have been suggested for advanced vulvar cancers. Due to the low incidence of the disease, the level of evidence for the success of these treatment modalities is poor. In countries like India, a heterogeneous incidence of vulvar carcinoma exists across the country, with patients presenting at advanced stages when the option of surgery is often supplemented or replaced by chemotherapy and radiotherapy. In this review, we attempt to study the available published literature and trials and discuss the treatment options in various stages of vulvar carcinoma.

Resurrection of whole liver radiotherapy—A case report

INTRODUCTIONnThis is a case report of a patient of lymphoma with liver metastasis who had persistent pain and jaundice despite multiple lines of chemotherapy. She underwent palliative liver irradiation. This is an uncommon modality due to fear of radiation induced hepatitis. We reviewed literature available on the use of liver irradiation for palliation and concluded that it can be safely used with good results. A 33-year-old female with Non-Hodgkins Lymphoma (NHL) presented with obstructive jaundice. She underwent stenting followed by chemotherapy. She was lost to follow up to later present with a progressively increasing right hypochondrial mass, pain and icterus. Ultrasound abdomen revealed massive hepatomegaly with hypodense lesions in both liver lobes and centring the porta with dilatation of biliary radicals. Despite multiple lines of chemotherapy and use of opioids, there was no symptomatic relief in pain, size of mass or any decrease in biochemical parameters. Then she was offered palliative radiation in the form of partial liver irradiation to a dose of 21Gy/7 fractions. She had >50% pain relief after 2 fractions and was off opioids by last fraction. Liver span reduced from 6cm to 1cm below costal margin in mid clavicular line. Radiologically 60% reduction in size of liver lesions was observed. Also, a decreasing trend in biochemical parameters was observed. Use of whole or partial liver irradiation is rare in clinical practice due to fear of radiation induced hepatitis by conventional techniques. Newer techniques of delivering radiation can highly improvise accuracy and permit further dose escalation.

Dosimetric Comparison of Pencil-Beam Scanning and Photon-Based Radiation Therapy as a Boost in Carcinoma of Cervix

PurposenBrachytherapy is essential for local treatment in cervical carcinoma, but some patients are not suitable for it. Presently, for these patients, the authors prefer a boost by using intensity-modulated radiation therapy (IMRT). The authors evaluated the dosimetric comparison of proton-modulated radiation therapy versus IMRT and volumetric-modulated arc therapy (VMAT) as a boost to know whether protons can replace photons.nnnPatients and MethodsnFive patients who received external beam radiation therapy to the pelvis by IMRT were reviewed. Three different plans were made, including pencil beam scanning (PBS), IMRT, and VMAT. The prescribed planning target volume (PTV) was 20 Gy in 4 fractions. The dose to 95% PTV (D95%), the conformity index, and the homogeneity index were evaluated for PTV. The Dmax, D2cc, and Dmean were evaluated for organs at risk along with the integral dose of normal tissue and organs at risk.nnnResultsnThe PTV coverage was optimal and homogeneous with modulated protons and photons. For PBS, coverage D95% was 20.01 ± 0.02 Gy (IMRT, 20.08 ± 0.06 Gy; VMAT, 20.1 ± 0.04 Gy). For the organs at risk, Dmax of the bladder for PBS was 21.05 ± 0.05 Gy (IMRT, 20.8 ± 0.21 Gy; VMAT, 21.65 ± 0.41 Gy) while the Dmax for the rectum for PBS was 21.04 ± 0.03 Gy (IMRT, 20.81 ± 0.12 Gy; VMAT, 21.66 ± 0.38 Gy). Integral dose to normal tissues in PBS was 14.17 ± 2.65 Gy (IMRT, 25.29 ± 6.35 Gy; VMAT, 25.24 ± 6.24 Gy).nnnConclusionsnCompared with photons, modulated protons provide comparable conformal plans. However, PBS reduces the integral dose to critical structures significantly compared with IMRT and VMAT. Although PBS may be a better alternative for such cases, further research is required to substantiate such findings.

Dosimetric Comparison between Intensity Modulated Radiotherapy and 3 Dimensional Conformal Radiotherapy in the Treatment of Rectal Cancer

Objective: To compare dosimetric parameters of 3 dimensional conformal radiotherapy (3 DCRT) and intensity modulated radiotherapy (IMRT) in terms of target coverage and doses to organs at risk (OAR) in the management of rectal carcinoma. Methods: In this prospective study, conducted between August 2014 and March 2016, all patients underwent CT simulation along with a bladder protocol and target contouring according to the Radiation Therapy Oncology Group (RTOG) guidelines. Two plans were made for each patient (3 DCRT and IMRT) for comparison of target coverage and OAR. Result: A total of 43 patients were recruited into this study. While there were no significant differences in mean Planning Target Volume (PTV) D95% and mean PTV D98% between 3 DCRT and IMRT, mean PTV D2% and mean PTV D50% were significantly higher in 3 DCRT plans. Compared to IMRT, 3 DCRT resulted in significantly higher volumes of hot spots, lower volumes of cold spots, and higher doses to the entire OAR. Conclusion: This study demonstrated that IMRT achieves superior normal tissue avoidance (bladder and bowel) compared to 3 DCRT, with comparable target dose coverage.

Improving the accuracy of target volume delineation by combined use of computed tomography, magnetic resonance imaging and positron emission tomography in head and neck carcinomas

OBJECTIVEnConformal radiation therapy mandates accurate delineation of target volumes, which requires incorporation of modern imaging modalities like magnetic resonance imaging (MRI) and positron emission tomography (PET) in addition to conventionally used computed tomography (CT). This can resolve discrepancies in target delineation in head and neck carcinomas resulting in better local control. We hereby report the comparison of Gross Tumor Volumes (GTVs) (primary) drawn using PET, CT and MRI and their concordance indices.nnnMETHODS AND MATERIALnTwenty five patients with head and neck cancer were taken into this study. MRI, PET and CT planning scans were done as per standard guidelines. Three sets of primary GTVs namely GTV- PET, GTV-CT and GTV-MRI were contoured on fused images. All the three volumes and concordances among the volumes were analyzed.nnnRESULTnThe mean GTV-CT, GTV-PET and GTV-MRI volumes were 29.65 cc ± 31.27, 32.05 cc ± 33.75 and 24.85 cc ± 25.28 respectively. There was a significant difference in the GTV-MRI & GTV-CT volumes (P = 0.023) and GTV-PET & GTV-MRI volumes (P = 0.049). However, there was no significant difference in the GTV-PET & GTV-CT volume (P = 0.468). The mean CI (PET-MRI), CI (CT-MRI) and CI (PET-CT) was 0.42, 0.46 and 0.47 respectively, which depicts a moderate concordance.nnnCONCLUSIONnPET and MRI are useful imaging tools in head and neck malignancies and should be used in conjunction with CT scan for improved target volume delineation.

Primary gastric Burkitt's lymphoma

The primary gastrointestinal non-Hodgkin’s lymphoma, although rare, is among the most common extra-nodal lymphomas, considering that gastric lymphomas are more common than intestinal lymphomas. Burkitt’s lymphoma (BL) is an aggressive form of B-cell lymphoma that is typically endemic in Africa, while non-endemic cases are found in the rest of the world. Primary gastric BL is extremely rare and only around 50 cases have been reported worldwide. Here we present the case of a young HIV-negative male, who was referred to our department with a stage IV gastric BL. He was planned for palliative chemotherapy, but after the first cycle of chemotherapy he succumbed to the progression of the disease.