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PURPOSE: A planning study was performed to evaluate the performance of volumetric modulated arc radiotherapy on head and neck cancer patients. Conventional fixed field IMRT was used as a benchmark. METHODS AND MATERIALS: CT datasets of 29 patients with squamous cell carcinoma of the oro-pharynx, hypo-pharynx and larynx were included. Plans for fixed beam IMRT, single (RA1) and double (RA2) modulated arcs with the RapidArc technique were optimised. Dose prescription was set to 66 Gy to the primary tumour (at 2.2 Gy/fraction), 60 Gy to intermediate-risk nodes and 54 Gy to low-risk nodal levels. The planning objectives for PTV were minimum dose >95%, and maximum dose <107%. Maximum dose to spinal cord was limited to 46 Gy, maximum to brain stem to 50 Gy. For parotids, mean dose <26 Gy (or median <30 Gy) was assumed as the objective. The MU and delivery time were scored to measure expected treatment efficiency. RESULTS: Target coverage and homogeneity results improved with RA2 plans compared to both RA1 and IMRT. All the techniques fulfilled the objectives on maximum dose, while small deviations were observed on minimum dose for PTV. The conformity index (CI(95%)) was 1.7+/-0.2 for all the three techniques. RA2 allowed a reduction of D(2%) to spinal cord of approximately 3 Gy compared to IMRT (RA1 D(2%) increased it of approximately 1 Gy). On brain stem, D(2%) was reduced from 12 Gy (RA1 vs. IMRT) to 13.5 Gy (RA2 vs. IMRT). The mean dose to ipsi-lateral parotids was reduced from 40 Gy (IMRT) to 36.2 Gy (RA1) and 34.4 Gy (RA2). The mean dose to the contra-lateral gland ranged from 32.6 Gy (IMRT) to 30.9 Gy (RA1) and 28.2 Gy (RA2). CONCLUSION: RapidArc was investigated for head and neck cancer. RA1 and RA2 showed some improvements in organs at risk and healthy tissue sparing, while only RA2 offered improved target coverage with respect to conventional IMRT.

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The use of Ifosfamide-based chemotherapy in primary nasopharyngeal carcinoma (NPC), in neoadjuvant settings [NACT] has not been sufficiently evaluated. We present here a retrospective analysis of 78 patients of untreated, locoregionally advanced NPC patients who received Ifosfamide-Cisplatin-based NACT at our institute from 1997 to 2004. Definitive treatment comprised radical radiotherapy (RT) or concurrent chemoradiotherapy (CCRT) using weekly Cisplatin. Post-NACT, 92% patients had a partial response (PR) while 3% had a complete locoregional response (CR). The rates of CR increased to 87% after completion of definitive treatment. With follow up (38 months), 29% patients developed recurrent/persistent disease. The local and locoregional control rates at 5 years were 76% and 73%, respectively. The 5-year overall survival (OAS) was 80% and disease-free survival was 65%. Grade III or more neutropenia was seen in 15%. Results of Ifosfamide-Cisplatin combination as a NACT in advanced NPC have been quite encouraging and need to be exploited further.

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PURPOSE: A treatment planning study was performed to evaluate the performance of the novel volumetric modulated single arc radiotherapy on cervix uteri cancer patients. Conventional fixed field IMRT was used as benchmark. METHODS AND MATERIALS: CT datasets of eight patients were included in the study. Plans were optimised with the aim to assess organs at risk and healthy tissue sparing while enforcing highly conformal target coverage. Planning objectives for PTV were: maximum significant dose lower than 52.5 Gy and minimum significant dose higher than 47.5 Gy. For organs at risk, the median and maximum doses were constrained to be lower than 30 (rectum), 35 (bladder) and 25 Gy (small bowel) and 47.5 Gy; additional objectives were set on various volume thresholds. Plans were evaluated on parameters derived from dose volume histograms and on NTCP estimates. Peripheral doses at 5, 10 and 15 cm from the PTV surface were recorded to assess the low-level dose bath. The MU and delivery time were scored to measure expected treatment efficiency. RESULTS: Both RapidArc and IMRT resulted in equivalent target coverage but RapidArc had an improved homogeneity (D(5%)-D(95%) = 3.5 +/- 0.6 Gy for RapidArc and 4.3 +/- 0.8 Gy for IMRT) and conformity index (CI(90%) = 1.30 +/- 0.06 for RapidArc and 1.41 +/- 0.15 for IMRT). On rectum the mean dose was reduced by about 6 Gy (10 Gy for the rectum fraction not included in the PTV). Similar trends were observed for the various dose levels with reductions ranging from approximately 3 to 14.4 Gy. For the bladder, RapidArc allowed a reduction of mean dose ranging from approximately 4 to 6Gy and a reduction from approximately 3 to 9 Gy w.r.t. IMRT. Similar trends but with smaller absolute differences were observed for the small bowel and left and right femur. NTCP calculations on bladder and rectum confirmed the DVH data with a potential relative reduction ranging from 30 to 70% from IMRT to RapidArc. The healthy tissue was significantly less irradiated in the medium to high dose regions (from 20 to 30 Gy) and the integral dose reduction with RapidArc was about 12% compared to IMRT. Concerning peripheral dose, the relative difference between IMRT and RapidArc was of 9 +/- 2%, 43 +/- 11% and 36 +/- 5% at 5, 10 and 15 cm from the PTV surface, respectively. The MU/Gy from RapidArc was 245 +/- 17 corresponding to an expected average beam on time of 73 +/- 10 s per fractions of 2 Gy. IMRT plans presented higher values with an average of MU/Gy = 479 +/- 63. CONCLUSION: RapidArc was investigated for cervix uteri cancer showing significant improvements in organs at risk and healthy tissue sparing with uncompromised target coverage leading to better conformal avoidance of treatments w.r.t. conventional IMRT. This, in combination with the confirmed short delivery time, can lead to clinically significant advances in the management of this highly aggressive cancer type. Clinical protocols are now advised to evaluate prospectively the potential benefit observed at the planning level.

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BACKGROUND: Set-up errors are an inherent part of radiation treatment process. Coverage of target volume is a direct function of set-up margins, which should be optimized to prevent inadvertent irradiation of adjacent normal tissues. The aim of this study was to evaluate three-dimensional (3D) set-up errors and propose optimum margins for target volume coverage in head and neck radiotherapy. METHODS: The dataset consisted of 93 pairs of orthogonal simulator and corresponding portal images on which 558 point positions were measured to calculate translational displacement in 25 patients undergoing conventional head and neck radiotherapy with antero-lateral wedge pair technique. Mean displacements, population systematic (Sigma) and random (sigma) errors and 3D vector of displacement was calculated. Set-up margins were calculated using published margin recipes. RESULTS: The mean displacement in antero-posterior (AP), medio-lateral (ML) and supero-inferior (SI) direction was -0.25 mm (-6.50 to +7.70 mm), -0.48 mm (-5.50 to +7.80 mm) and +0.45 mm (-7.30 to +7.40 mm) respectively. Ninety three percent of the displacements were within 5 mm in all three cardinal directions. Population systematic (Sigma) and random errors (sigma) were 0.96, 0.98 and 1.20 mm and 1.94, 1.97 and 2.48 mm in AP, ML and SI direction respectively. The mean 3D vector of displacement was 3.84 cm. Using van Herk's formula, the clinical target volume to planning target volume margins were 3.76, 3.83 and 4.74 mm in AP, ML and SI direction respectively. CONCLUSION: The present study report compares well with published set-up error data relevant to head and neck radiotherapy practice. The set-up margins were <5 mm in all directions. Caution is warranted against adopting generic margin recipes as different margin generating recipes lead to a different probability of target volume coverage.

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BACKGROUND: The purpose was to evaluate the prognostic factors and treatment outcome of Indian patients with primary diffuse large B-cell lymphoma (DLBCL) of the tonsil treated at a single institution. METHODS: In all, 121 patients with DLBCL of the tonsil, treated at the Tata Memorial Hospital, Mumbai, India, from January 1990 to December 2002, were included. The median age was 45 years and the majority of patients (68%) were males. Systemic symptoms were present in 12% of patients; 28% presented with stage I and 67% had stage II disease. Treatment consisted of a combination of chemotherapy (CTh) and radiotherapy (RT) for the majority of patients (69.4%). Among those receiving RT, 64% received an RT dose of > or =45 Gy. RESULTS: After a median follow-up of 62 months, disease-free survival (DFS) and overall survival (OS) were 66.4% and 81.6%, respectively. Significant prognostic factors included: WHO performance score > or =2 (OS: 72.1% vs 95.6%, P = .016), bulky tumors (OS: 68.5% vs 86.9%, P = .001), presence of B-symptoms (OS: 36.7% vs 79.6%, P < .001), and Ann Arbor stage. On multivariate analysis; WHO performance score > or =2 (hazard ratio [HR], 4.27; 95% confidence interval [CI], 1.20-15.12), and B symptoms (HR, 6.27; 95% CI, 2.38-16.48), retained statistical significance. CTh + RT resulted in a significantly better outcome than those treated with CTh alone (OS: 85.7% vs 70.7%, P = .008). The complete response (P = .053), DFS (P = .039), and OS (P = .014) rates were significantly better for patients receiving an RT dose > or =45 Gy. CONCLUSIONS: Tumor bulk, WHO performance score, the presence of B symptoms, and Ann Arbor stage significantly influence outcome. A combined modality treatment, consisting of CTh and RT (with an RT dose of > or =45 Gy), results in a satisfactory outcome in patients with this uncommon neoplasm.

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This single institutional study evaluated the prognostic factors and treatment outcome of 113 Indian patients with primary nasopharyngeal non-Hodgkin's lymphoma. At presentation, 28% had stage I and 62% had stage II disease. Treatment comprised of a combination of chemotherapy (CTh) and radiotherapy (RT) in the majority of the patients (76%). After a median follow-up of 56 months, the 5-year disease-free survival (DFS) and overall survival (OS) for the whole group were 55.8% and 57.9%, respectively. Multivariate analysis showed that; age > 30 years [hazard ratio (HR) = 6.59, 95% confidence interval (CI) = 2.59 - 16.7, P < 0.0001], WHO performance score > or = 2 (HR = 2.34, 95% CI = 1.01 - 5.46, P = 0.050), T-cell lymphomas (HR = 2.81, 95% CI = 1.14 - 6.96, P < 0.001) and the presence of B symptoms (HR = 3.65, 95% CI = 1.77 - 7.53, P = 0.025), had a negative influence on survival. Patients treated with a combination of CTh and RT had a significantly better outcome than those treated with CTh alone (OS: 69%vs. 31%, P < 0.00001). HR for death in the CTh alone group was 3.73 (95% CI = 1.95 - 7.13). The CR (P = 0.01), DFS (P = 0.01) and OS (P = 0.03) rates were significantly better for patients receiving a RT dose of > or =4500 cGy. HR in the subgroup that received a RT dose of <4500 cGy was 2.51 (95% CI = 1.04 - 6.06). These results suggest that combined modality treatment, comprising of CTh and RT (with an RT dose of > or =4500 cGy), results in satisfactory outcome in patients with this rare neoplasm.

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BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is one of the leading cancers in India. Since a large majority present in loco-regionally advanced stages, surgery followed by adjuvant post-operative radiotherapy (PORT) has been the mainstay of treatment for resectable HNSCC. AIM: To identify clinico-pathologic factors that could have an impact on outcome in HNSCC in the postoperative setting. MATERIALS AND METHODS: A retrospective review of 348 previously untreated patients with HNSCC who received PORT following curative surgery. The outcome measures were local control, loco-regional control, and disease free survival (DFS). RESULTS: With a median follow-up of 36 months (range: 2-127 months) for surviving patients, the 5-year local control, loco-regional control, and DFS was 79%, 63%, and 56%, respectively for all patients. On univariate analysis, site of primary was an independent prognostic factor for all the outcome measures (P = 0.005, 0.02, and 0.04, respectively) with oral cavity lesions faring the worst. Peri-nodal extension (PNE) affected loco-regional control (P = 0.002) and DFS (P = 0.0005), but was not predictive for local control (P = 0.9852). Cut margin positivity predicted for inferior local control alone (P = 0.03), the significance of which was lost on multivariate analysis. Cox regression analysis however confirmed the significance of primary site and PNE as independent prognostic factors. CONCLUSION: Primary site and PNE are independent factors predicting outcome in the postoperative radiotherapeutic management of HNSCC.

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Metastasis to the prostate is extremely uncommon. We report a 38-year-old man with sigmoid colon carcinoma, treated with surgery and adjuvant chemotherapy, who developed isolated metastasis to the prostate four years after initial treatment. He was treated with chemoradiation and remains disease-free three years after detection of metastasis.

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PURPOSE: To evaluate the variability in catheter length, geometry, and dosimetric parameters of radical intraoperative high-dose-rate breasts implant during 7-11 days. METHODS AND MATERIALS: Simulator X-rays, CT scans, and dosimetric studies were repeated on alternate days in 14 consecutive patients treated with radical intraoperative two- or three-plane nylon catheter high-dose-rate implant (34 Gy in 10 fractions within 5 days). RESULTS: Significant variation was found in catheter length, but no major change was noted in implant geometry, homogeneity, or inhomogeneity indexes. A variation in length of >5 mm in one or more catheters was seen in all patients and >10 mm in 11 patients at any time during the implant. Of the 171 catheters in 14 patients, 100 (58%) and 38 (22%) showed a variation of >5 mm or >10 mm, respectively. The variation of >10 mm was reduced from 32% of catheters in the first 5 patients to 17% in the subsequent 9 patients (p = 0.028). Rigid catheter fixation might reduce length variation but may cause skin necrosis if the expanding cavity indents the skin for a long period against the fixation device. A dose homogeneity index of 0.90 (range 0.85-0.92) and dose nonuniformity ratio of 0.20 (range 0.12-0.25) were satisfactory. CONCLUSION: The catheter fixation and exit catheter length should be measured daily and if the implant is in situ for more than a few days, orthogonal X-rays and, if indicated, dosimetry should be repeated at least once.

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