Implications of contrast-enhanced CT-based and MRI-based target volume delineations in radiotherapy treatment planning for brain tumors.

Delineation of various target volumes using contrast-enhanced magnetic resonance imaging (MRI) and/or computed tomography (CT) constitutes the primary step for radiation therapy planning (RTP) in brain tumors. This study presents a quantification and comparative evaluation of the various clinical target volumes (CTV) and gross target volumes (GTV) as outlined by contrast-enhanced CT and MRI, along with its implications for postoperative radiotherapy of brain tumors. Twenty-one patients of gliomas were considered for this prospective study. Peritumoral edema as CTV and residual tumor as GTV were delineated separately in postoperative contrast-enhanced CT and MRI. These volumes were estimated separately and their congruence studied for contrast-enhanced CT and MRI. Compared to MRI, CT underestimated the volumes, with significant differences seen in the mean CTV (mean +/- SD: -62.92 +/- 93.99 cc; P = 0.006) and GTV (mean +/- SD: -21.08 +/- 36.04 cc; P = 0.014). These differences were found to be significant for high-grade gliomas (CTV: P = 0.045; GTV: P = 0.044), while they were statistically insignificant for low-grade gliomas (CTV: P = 0.080; GTV: P = 0.117). The mean differences in the volumes for CTV and GTV were estimated to be -106.7% and -62.6%, respectively, taking the CT volumes as the baseline. Thus, even though, electron density information from CT is essential for RTP, target delineation during postoperative radiotherapy of brain tumors, especially for high-grade tumors, should be based on MRI so as to avoid inadvertent geographical misses, especially in the regions of peritumoral edema.

Bone metastasis from ovarian cancer.

We report a case of epithelial ovarian cancer, which presented with lumbar vertebral metastasis soon after treatment, as a part of distant spread. This patient was then treated by palliative radiotherapy and put on second line chemotherapy i.e, Topotecan. She responded to treatment well.

Factors influencing the development of ulcers and strictures in carcinoma of the esophagus treated with radiotherapy with or without concurrent chemotherapy.

PURPOSE: To ascertain factors that could influence the development of ulcers and strictures in the definitive management of squamous cell carcinoma (SCC) of esophagus treated with external beam radiotherapy (EBRT), high-dose-rate (HDR) intralumenal radiotherapy (ILRT) with or without concurrent weekly cisplatin (CDDP @ 35 mg/m2) chemotherapy (CT). MATERIALS AND METHODS: Between 1990-2005, 244 patients with inoperable SCC of esophagus were identified from our database and grouped into one of the following: those receiving at least 60 Gy EBRT (Gp E, n=44); EBRT followed by HDR-ILRT (Gp E+I, n=98); at least 50 Gy EBRT with CT (Gp E+C, n=68); EBRT+HDR-ILRT + CT (Gp E+I+C, n=34). Ulcers (discovered on endoscopy) and strictures evident on a barium swallow (which needed dilatations) were scored as treatment induced, if the biopsy was negative. Factors likely to influence their outcome were analyzed. RESULTS: The groups were matched for all patient and disease characteristics except pretreatment hemoglobin and Karnofsky performance score (KPS), which were lower in Gp E. The incidence of ulcers was 7%, 8%, 6% and 21% (P=0.08) while that of strictures was 14%, 9%, 21% and 41% (P=0.00) for the groups E, E+I, E+C and E+I+C respectively. On univariate analysis, patients with better KPS (P=0.03), treated with narrow applicators (6 mm vs. 10 mm, P=0.00), received CT (P=0.00) or assigned to Gp E+I+C (P =0.00) were more likely to develop strictures, with a trend for development of ulcers in Gp. E+I+C (P=0.08). Logistic regression retained only Gp E+I+C for development of ulcers (OR 10.36, 95% CI 1.2-89.1, P=0.03) and strictures (OR 4.2, 95% CI 1.4-12.6, P=0.00). CONCLUSION: Treatment intensification as in Gp E+I+C results in about a three-fold increase in treatment induced late morbidity which can adversely impact on swallowing function and therefore emphasizes the need for optimisation of HDR-ILRT when used in a CT+RT protocol.

Carcinoma of uterine cervix with isolated metastasis to fibula and its unusual behavior: report of a case and review of literature.

Bone metastasis from carcinoma cervix is uncommon, especially in the distal appendicular skeleton. A 36 year old lady presented with carcinoma of uterine cervix, FIGO, stage IIb. She was treated with radical radiotherapy. Nine months later, she developed an isolated lytic lesion in right fibula, which turned out to be a metastatic lesion. The patient is doing well, 3 years after the surgical excision of metastasis. This is one of the few documented cases of metastasis to fibula, arising from carcinoma of uterine cervix and probably the first with isolated metastasis of this site. Unlike the dismal outcome commonly seen in patients with bone secondaries, she continues to be disease free and alive at 39 months of follow up, after the development of skeletal metastasis.

Medulloblastomas: clinical profile, treatment techniques and outcome - an institutional experience.

The present series reports an audit on the patterns of presentation, radiation treatment techniques, failure pattern and outcome in the 36 patients treated at a single institution. Patients were accrued between October 1991 and September 1999. They underwent total or subtotal resection along with craniospinal irradiation. The dose to the cranium ranged from 30 to 43Gy (median- 36Gy), to the spine from 20 - 36Gy (median- 36Gy) and the posterior fossa boost, which was delivered in 32 cases, ranged from 14 to 24Gy (median -18Gy). Simulator film evaluation was carried out at the time of analysis based on the French Medulloblastoma Group guidelines, which revealed a significant under-dosage in the region of posterior fossa and cribriform plate in 27% and 19% respectively. Adjuvant chemotherapy was administered in 7 patients. Salvage treatment in the form of chemotherapy (5 cases) and re-irradiation (2 cases) were attempted but were ineffective. The overall survival (OS) and progression free survival (PFS) rates were 54% and 40% respectively, with the median being 75 and 29 months respectively. Amongst all the prognostic factors considered, on univariate analysis, duration of symptoms was significant for PFS with a trend towards significance for OS, while extent of debulking had a trend towards significance for PFS. No factor emerged significant on multivariate analysis.