What is the role of routine follow-up for localised limb soft tissue sarcomas? A retrospective analysis of 174 patients.

BACKGROUND: There are neither prospective data nor agreement on the optimal routine follow-up procedures in patients treated for soft tissue sarcoma of the limb. METHODS: Data on 174 consecutive patients with a soft tissue sarcoma of the limb undergoing follow-up by oncologists at a single centre from 2003 to 2009 were included in this analysis. The rate and site of recurrence and mode of detection were analysed. Outcome of the patients was assessed. RESULTS: Eighty-two patients (47%) experienced relapse of any type. Isolated local recurrence occurred in 26 patients and local relapse with synchronous pulmonary metastases in five patients. Local recurrences were detected clinically in 30 of these 31 patients; magnetic resonance imaging identified only one local recurrence. Twenty-eight patients developed isolated lung metastases; in nine patients these were amenable to resections, seven of whom are currently free of disease after treatment. Lung metastases were detected by chest x-ray (CXR) in 19 patients, computed tomography scanning in 3 patients, and clinically in 11 patients. Twenty-three patients developed non-pulmonary metastases. More than 80% of relapses occurred in the first 2 years of follow-up; however, later recurrences were also observed. CONCLUSIONS: Routine follow-up CXR can detect lung metastases suitable for surgical resection, although the optimal interval of imaging has yet to be defined. Local relapse is almost always detected by patients or physicians, and routine scanning of the primary site is of doubtful benefit. Patient and physician education to detect local relapse may be helpful. Prospective evaluation of follow-up is recommended.

Regulatory T cells in the control of autoimmunity: the essential role of transforming growth factor beta and interleukin 4 in the prevention of autoimmune thyroiditis in rats by peripheral CD4(+)CD45RC- cells and CD4(+)CD8(-) thymocytes.

Previous studies have shown that induction of autoimmune diabetes by adult thymectomy and split dose irradiation of PVG.RT1(u) rats can be prevented by their reconstitution with peripheral CD4(+)CD45RC-TCR-alpha/beta+RT6(+) cells and CD4(+)CD8(-) thymocytes from normal syngeneic donors. These data provide evidence for the role of regulatory T cells in the prevention of a tissue-specific autoimmune disease but the mode of action of these cells has not been reported previously. In this study, autoimmune thyroiditis was induced in PVG.RT1(c) rats using a similar protocol of thymectomy and irradiation. Although a cell-mediated mechanism has been implicated in the pathogenesis of diabetes in PVG.RT1(u) rats, development of thyroiditis is independent of CD8(+) T cells and is characterized by high titers of immunoglobulin (Ig)G1 antithyroglobulin antibodies, indicating a major humoral component in the pathogenesis of disease. As with autoimmune diabetes in PVG. RT1(u) rats, development of thyroiditis was prevented by the transfer of CD4(+)CD45RC- and CD4(+)CD8(-) thymocytes from normal donors but not by CD4(+)CD45RC+ peripheral T cells. We now show that transforming growth factor (TGF)-beta and interleukin (IL)-4 both play essential roles in the mechanism of this protection since administration of monoclonal antibodies that block the biological activity of either of these cytokines abrogates the protective effect of the donor cells in the recipient rats. The prevention of both diabetes and thyroiditis by CD4(+)CD45RC- peripheral cells and CD4(+)CD8(-) thymocytes therefore does not support the view that the mechanism of regulation involves a switch from a T helper cell type 1 (Th1) to a Th2-like response, but rather relies upon a specific suppression of the autoimmune responses involving TGF-beta and IL-4. The observation that the same two cytokines were implicated in the protective mechanism, whether thymocytes or peripheral cells were used to prevent autoimmunity, strongly suggests that the regulatory cells from both sources act in the same way and that the thymocytes are programmed in the periphery for their protective role. The implications of this result with respect to immunological homeostasis are discussed.

Peripheral autoantigen induces regulatory T cells that prevent autoimmunity.

Previous studies have shown that autoimmune thyroiditis can be induced in normal laboratory rats after thymectomy and split dose gamma-irradiation. Development of disease can be prevented by reconstitution of PVG rats shortly after their final irradiation with either peripheral CD4(+)CD45RC- T cells or CD4(+)CD8(-) thymocytes from syngeneic donors. Although the activity of both populations is known to depend on the activities of endogenously produced interleukin 4 and transforming growth factor beta, implying a common mechanism, the issue of antigen specificity of the cells involved has not yet been addressed. In this study, we show that the regulatory T cells that prevent autoimmune thyroiditis are generated in vivo only when the relevant autoantigen is also present. Peripheral CD4(+) T cells, from rats whose thyroids were ablated in utero by treatment with 131I, were unable to prevent disease development upon adoptive transfer into thymectomized and irradiated recipients. This regulatory deficit is specific for thyroid autoimmunity, since CD4(+) T cells from 131I-treated PVG.RT1(u) rats were as effective as those from normal donors at preventing diabetes in thymectomized and irradiated PVG.RT1(u) rats. Significantly, in contrast to the peripheral CD4(+) T cells, CD4(+)CD8(-) thymocytes from 131I-treated PVG donors were still able to prevent thyroiditis upon adoptive transfer. Taken together, these data indicate that it is the peripheral autoantigen itself that stimulates the generation of the appropriate regulatory cells from thymic emigrant precursors.

The thymus contains a high frequency of cells that prevent autoimmune diabetes on transfer into prediabetic recipients.

Rats of the PVG.RT1u strain develop autoimmune diabetes when thymectomized at 6 wk of age and are rendered relatively lymphopenic by a cumulative dose of 1,000 rads 137Cs gamma-irradiation given in four split doses. Previous studies have shown that the disease is prevented by the intravenous injection of 5 x 10(6) CD4+ CD45RC-TCR alpha beta+ RT6+ peripheral T cells from normal syngeneic donors. These cells have a memory phenotype and are presumably primed to some extrathymic antigen. However, we now report that the CD4+ CD8- population of mature thymocytes is a very potent source of cells, with the capacity to prevent diabetes in our lymphopenic animals. As few as 6 x 10(5) of these cells protect approximately 50% of recipients and the level of protection increases with cell dose. It appears that one characteristic of the intrathymic selection of the T cell repertoire is the generation of cells that regulate the autoimmune potential of peripheral T cells that have been neither clonally deleted intrathymically nor rendered irreversibly anergic in the periphery.

Sensory adaptation in naive peripheral CD4 T cells.

T cell receptor interactions with peptide/major histocompatibility complex (pMHC) ligands control the selection of T cells in the thymus as well as their homeostasis in peripheral lymphoid organs. Here we show that pMHC contact modulates the expression of CD5 by naive CD4 T cells in a process that requires the continued expression of p56(lck). Reduced CD5 levels in T cells deprived of pMHC contact are predictive of elevated Ca(2)+ responses to subsequent TCR engagement by anti-CD3 or nominal antigen. Adaptation to peripheral pMHC contact may be important for regulating naive CD4 T cell responsiveness.

IMRiS phase II study of IMRT in limb sarcomas: Results of the pre-trial QA facility questionnaire and workshop.

INTRODUCTION: Soft tissue sarcomas of the extremities (STSE) are rare malignancies. We report current UK practice for immobilisation of soft tissue sarcoma of STSE, as part of the initial study set-up within the IMRiS trial, a phase II study of intensity modulated radiotherapy (IMRT) in primary bone and soft tissue sarcoma. METHODS: A facility questionnaire (FQ) was circulated to 29 IMRiS centres investigating the variation in immobilisation devices, planning techniques, and imaging protocols. A workshop was held to address concerns raised by centres. It focused on STSE immobilisation and patient set-up. Robustness of patient set-up at each centre was evaluated based on the following criteria: evidence of local set-up audit, calculation of margins based on set-up audit results, imaging frequency, and number of patients treated per centre per annum. RESULTS: Twenty-seven (93%) questionnaires were returned. 30% (8/27) of responders routinely treated STSE with IMRT. The remaining 70% (19/27) had little or no experience with IMRT for STSE. Vacuum bags were the most frequent immobilisation device (9/27), followed by thermoplastic shells (7/27). Nine centres had audited their local set-up; however, only 4 had calculated margins in response to the results. Ten centres were classified as having high level of robustness. CONCLUSIONS: Immobilisation devices and planning techniques for STSE are inconsistent across centres. Robustness of set-up is an important tool to ensure quality of results in a multicentre trial setting with such different levels of experience. The IMRiS trial Quality Assurance programme encourages centres to assess robustness of set-up through local audit and subsequent calculation of treatment margins. IMPLICATIONS FOR PRACTICE: This is the first study that used robustness criteria to tailor QA support to individual centres.

A phase I study of the nitroimidazole hypoxia marker SR4554 using 19F magnetic resonance spectroscopy.

BACKGROUND: SR4554 is a fluorine-containing 2-nitroimidazole, designed as a hypoxia marker detectable with 19F magnetic resonance spectroscopy (MRS). In an initial phase I study of SR4554, nausea/vomiting was found to be dose-limiting, and 1400 mg m(-2) was established as MTD. Preliminary MRS studies demonstrated some evidence of 19F retention in tumour. In this study we investigated higher doses of SR4554 and intratumoral localisation of the 19F MRS signal. METHODS: Patients had tumours > or = 3 cm in diameter and < or = 4 cm deep. Measurements were performed using 1H/19F surface coils and localised 19F MRS acquisition. SR4554 was administered at 1400 mg m(-2), with subsequent increase to 2600 mg m(-2) using prophylactic metoclopramide. Spectra were obtained immediately post infusion (MRS no. 1), at 16 h (MRS no. 2) and 20 h (MRS no. 3), based on the SR4554 half-life of 3.5 h determined from a previous study. 19Fluorine retention index (%) was defined as (MRS no. 2/MRS no. 1)*100. RESULTS: A total of 26 patients enrolled at: 1400 (n=16), 1800 (n=1), 2200 (n=1) and 2600 mg m(-2) (n=8). SR4554 was well tolerated and toxicities were all < or = grade 1; mean plasma elimination half-life was 3.7+/-0.9 h. SR4554 signal was seen on both unlocalised and localised MRS no. 1 in all patients. Localised 19F signals were detected at MRS no. 2 in 5 out of 9 patients and 4 out of 5 patients at MRS no. 3. The mean retention index in tumour was 13.6 (range 0.6-43.7) compared with 4.1 (range 0.6-7.3) for plasma samples taken at the same times (P=0.001) suggesting (19)F retention in tumour and, therefore, the presence of hypoxia. CONCLUSION: We have demonstrated the feasibility of using 19F MRS with SR4554 as a potential method of detecting hypoxia. Certain patients showed evidence of 19F retention in tumour, supporting further development of this technique for detection of tumour hypoxia.

Long-term survival but impaired homeostatic proliferation of Naïve T cells in the absence of p56lck.

Interactions between the T cell receptor (TCR) and major histocompatibility complex antigens are essential for the survival and homeostasis of peripheral T lymphocytes. However, little is known about the TCR signaling events that result from these interactions. The peripheral T cell pool of p56lck (lck)-deficient mice was reconstituted by the expression of an inducible lck transgene. Continued survival of peripheral naïve T cells was observed for long periods after switching off the transgene. Adoptive transfer of T cells from these mice into T lymphopoienic hosts confirmed that T cell survival was independent of lck but revealed its essential role in TCR-driven homeostatic proliferation of naïve T cells in response to the T cell-deficient host environment. These data suggest that survival and homeostatic expansion depend on different signals.

Long-term efficacy of imatinib mesylate in patients with advanced Tenosynovial Giant Cell Tumor.

Tenosynovial giant cell tumors (TGCT), are rare colony stimulating factor-1(CSF-1)-driven proliferative disorders affecting joints. Diffuse-type TGCT often causes significant morbidity due to local recurrences necessitating multiple surgeries. Imatinib mesylate (IM) blocks the CSF-1 receptor. This study investigated the long term effects of IM in TGCT. We conducted an international multi-institutional retrospective study to assess the activity of IM: data was collected anonymously from individual patients with locally advanced, recurrent or metastatic TGCT. Sixty-two patients from 12 institutions across Europe, Australia and the United States were identified. Four patients with metastatic TGCT progressed rapidly on IM and were excluded for further analyses. Seventeen of 58 evaluable patients achieved complete response (CR) or partial response (PR). One- and five-year progression-free survival rates were 71% and 48%, respectively. Thirty-eight (66%) patients discontinued IM after a median of 7 (range 1-80) months. Reported adverse events in 45 (78%) patients were among other edema (48%) and fatigue (50%), mostly grade 1-2 (89%). Five patients experienced grade 3-4 toxicities. This study confirms, with additional follow-up, the efficacy of IM in TGCT. In responding cases we confirmed prolonged IM activity on TGCT symptoms even after discontinuation, but with high rates of treatment interruption and additional treatments.

Gender differences in doxorubicin pharmacology for subjects with chemosensitive cancers of young adulthood.

PURPOSE: For many cancers, adolescents and young adults (AYA) have worse outcomes than for children and adults. Many factors may contribute to the AYA survival gap, including differences in biology, therapeutic intent, and adherence to therapy. It has been observed that male AYAs have poorer outcomes than females. The purpose of this work was to test the proposition that gender-related pharmacologic factors may account for a component of the AYA survival gap. PATIENTS AND METHODS: A prospective, multi-institutional pharmacologic study of 79 patients in total with chemosensitive cancers (Ewing sarcoma, osteosarcoma and Hodgkin lymphoma) was conducted, with conventional doxorubicin treatment. Pharmacokinetic data of 13 children, 40 AYAs and 13 adults were valid for analysis. Population pharmacokinetics models were developed for doxorubicin and its metabolite doxorubicinol based on the data created in this study. Consequently, model-based analysis was conducted to investigate the relevant topics. RESULTS: The clearance of doxorubicinol (normalized to body surface area), the main active metabolite of doxorubicin, appears faster in male AYAs than female (p = 0.04, 95% CI 0.1-3.9 L/h). The exposure of doxorubicinol (normalized to dose) is lower in male AYA than female (p = 0.03, 95% CI - 0.005 to - 0.0002 h/L). These might be correlated to the observed difference on nadir neutrophil count between male AYA and female (p = 0.027, 95% CI 0.09-1.4). CONCLUSION: Gender-related differences in doxorubicin pharmacology may account for worse outcomes for male AYAs with chemosensitive cancers compared to females. These findings may reduce the AYA survival gap compared to other age groups.

Mechanisms and management of non-islet cell tumour hypoglycaemia in gastrointestinal stromal tumour: case report and a review of published studies.

Tumour-related hypoglycaemia is a rare paraneoplastic phenomenon most frequently occurring with insulinomas, but also associated with non-islet cell tumours. It has been observed in a range of tumour types, but recently a small number of cases have been described in association with gastrointestinal stromal tumours. We describe a further case of a patient with gastrointestinal stromal tumour that was complicated by non-islet cell tumour hypoglycaemia, and discuss the mechanisms and management of non-islet cell tumour hypoglycaemia in the context of gastrointestinal stromal tumour.

Experience of the use of trabectedin (ET-743, Yondelis) in 21 patients with pre-treated advanced sarcoma from a single centre.

AIMS: Trabectedin (ET-743, Yondelis) is a marine-derived alkaloid that has two actions. It binds in the minor groove of DNA resulting in a conformational change; thus potentially altering interactions with transcription factors and other DNA binding proteins and it also interacts with the transcription-coupled nucleotide excision repair machinery to induce lethal double-stranded DNA breaks. In recent phase II trials it has shown considerable activity in the treatment of sarcomas. Here the use of trabectedin in patients with advanced refractory sarcoma from a single institution is presented. MATERIALS AND METHODS: Twenty-one patients with advanced refractory sarcoma from a single UK centre were treated with trabectedin on a named patient compassionate basis programme. All patients had received prior treatment with an anthracycline, and 95% had received ifosfamide. RESULTS: The patients received a median of four cycles of treatment. Objective partial responses were seen in three patients (14%) and a further eight patients (38%) achieved durable stable disease for a median duration of 4.5 months. The estimated 3- and 6-month progression-free survival was 58.8 and 17.6%, respectively. Six patients experienced early disease progression, and four patients died while on treatment. One death was due to treatment-related toxicity. Overall the drug was relatively well tolerated, with hepatic and haematological toxicities most commonly encountered. Both necessitated delays and/or dose reductions in a proportion of patients. Other significant toxicities were nausea, vomiting and asthenia. CONCLUSION: The disease responses and durable nature of disease stabilisation seen in a proportion of our patients support the continued investigational use of this drug in the treatment of advanced soft tissue sarcomas.

IL-4-producing ILC2s are required for the differentiation of TH2 cells following Heligmosomoides polygyrus infection.

Immunity to many human and murine gastrointestinal helminth parasites requires interleukin-4 (IL-4)-directed type 2 helper (TH2) differentiation of CD4+ T cells to elicit type-2 immunity. Despite a good understanding of the inflammatory cascade elicited following helminth infection, the initial source of IL-4 is unclear. Previous studies using the rat helminth parasite Nippostronglyus brasiliensis, identified an important role for basophil-derived IL-4 for TH2 differentiation. However, basophils are redundant for TH2 differentiation following infection with the natural helminth parasite of mice Heligmosomoides polygyrus, indicating that other sources of IL-4 are required. In this study using H. polygyrus, which is controlled by IL-4-dependent immunity, we identified that group-2 innate lymphoid cells (ILC2s) produced significant amounts of IL-4 and IL-2 following H. polygyrus infection. Leukotriene D4 was sufficient to stimulate IL-4 secretion by ILC2s, and the supernatant from activated ILC2s could potently drive TH2 differentiation in vitro in an IL-4-dependent manner. Furthermore, specific deletion of IL-4 from ILC2s compromised TH2 differentiation in vivo. Overall, this study highlights a previously unrecognized and important role for ILC2-derived IL-4 for TH2 differentiation in a natural TH2-dependent model of human helminthiasis.

Fatal radiation myelopathy after high-dose busulfan and melphalan chemotherapy and radiotherapy for Ewing's sarcoma: a review of the literature and implications for practice.

Radiation myelopathy is a rare, devastating, late effect of radiotherapy to the spinal cord. Spinal cord tolerance is currently accepted as about 50 Gy in 1.8-2 Gy fractions. However, the effect of chemotherapy on cord tolerance is unclear. This issue is important, given the increasing use of chemotherapy in combination with radiotherapy. We describe the case of a 17-year-old boy with a right apical paraspinal Ewing's tumour in the neck treated with induction chemotherapy, high-dose chemotherapy (busulfan and melphalan) with peripheral stem-cell rescue and, 4 months later, radiotherapy to the primary tumour site (cervical cord received 50 Gy in 30 fractions). After a latent period of 4 months, he developed a progressive, severe and ultimately fatal radiation myelopathy, which we suggest was due to a synergistic interaction between the high-dose chemotherapy and the radiotherapy. The use of such chemotherapy regimens in Ewing's tumours should be carefully considered, particularly when radiotherapy encompassing the spinal cord is an essential component of management.

Target volume definition in conformal radiotherapy for prostate cancer: quality assurance in the MRC RT-01 trial.

BACKGROUND AND PURPOSE: Prior to randomization of patients into the UK Medical Research Council multicentre randomized trial (RT-01) of conformal radiotherapy (CFRT) in prostate cancer, clinicians at participating centres were required to complete a quality assurance (QA) clinical planning exercise to enable an investigation of inter-observer variability in gross target volume (GTV) and normal structure outlining. MATERIALS AND METHODS: Thirteen participating centres and two investigators completed the clinical planning exercise of three practice planning cases. Clinicians were asked to draw outlines of the GTV, rectum and bladder on hard-copy computerized tomography (CT) films of the pelvis, which were transferred onto the Cadplan computer planning system by a single investigator. Centre, inferior and superior CT levels of GTV, rectum and bladder were noted, and volume calculations performed. Planning target volumes (PTV) were generated using automatic volume expansion of GTVs by a 1 cm margin. Anterior, right and left lateral beam eye views (BEV) of the PTVs were generated. Using a common central point, the BEV PTVs were superimposed for each beam direction of each case. Radial PTV variation was investigated by measurement of a novel parameter, termed the radial line measurement variation (RLMV). RESULTS: GTV central slice and length were defined with reasonable consistency. The RLMV analysis showed that the main part of the prostate gland, bladder and inferior rectum were outlined with good consistency among clinicians. However, the outlining of the prostatic apex, superior aspect of the prostate projecting into the bladder, seminal vesicles, the base of seminal vesicles and superior rectum were more variable. CONCLUSION: This exercise has demonstrated adequate consistency of GTV definition. The RLMV method of analysis indicates particular regions of clinician uncertainty. Appropriate feedback has been given to all participating clinicians, and the final RT-01 trial protocol has been modified to accommodate these findings.

Measurement of tumor oxygenation: in vivo comparison of a luminescence fiber-optic sensor and a polarographic electrode in the p22 tumor.

Hypoxia is important in tumor biology and therapy. This study compared the novel luminescence fiber-optic OxyLite sensor with the Eppendorf polarographic electrode in measuring tumor oxygenation. Using the relatively well-oxygenated P22 tumor, oxygen measurements were made with both instruments in the same individual tumors. In 24 air-breathing animals, pooled electrode pO(2) readings lay in a range over twice that of sensor pO(2(5min)) values (-3.2 to 80 mm Hg and -0.1 to 34.8 mm Hg, respectively). However, there was no significant difference between the means +/- 2 SE of the median pO(2) values recorded by each instrument (11.0 +/- 3.3 and 8.1 +/- 1.9 mm Hg, for the electrode and sensor respectively, P = 0.07). In a group of 12 animals treated with carbon monoxide inhalation to induce tumor hypoxia, there was a small but significant difference between the means +/- 2 SE of the median pO(2) values reported by the electrode and sensor (1.7 +/- 0.9 and 2.9 +/- 0.7 mm Hg, respectively, P = 0.009). A variable degree of disparity was seen on comparison of pairs of median pO(2) values from individual tumors in both air-breathing and carbon monoxide-breathing animals. Despite the differences between the sets of readings made with each instrument from individual tumors, we have shown that the two instruments provide comparable assessments of tumor oxygenation in groups of tumors, over the range of median pO(2) values of 0.6 to 28.1 mm Hg.

The physiological role of regulatory T cells in the prevention of autoimmunity: generation, specificity and mode of action.

Until recently, the traditional view was that tolerance to self antigens was maintained by a combination of physical deletion, in the thymus, and functional deletion, in the periphery, of autoreactive T cells. There is now, however, abundant evidence that the normal T cell repertoire contains overtly autoreactive T cells whose pathogenic potential is held in check by the activity of a distinct subset of peripheral T cells, the so-called regulatory or suppressor T cells. This article examines data from one model of rodent autoimmunity, where autoimmune pathology develops following thymectomy and irradiation of normal laboratory rats, which characterize the development and function of these so-called regulatory T cells.

The role of functional and molecular imaging in cancer drug discovery and development.

Studies of pharmacokinetics (which is what the body does to the drug) and pharmacodynamics (which is what the drug does to the body) are essential components of the modern process of cancer drug discovery and development. Defining the precise relationship between pharmacokinetics and pharmacodynamics is critical. It is especially important to establish a well understood pharmacological "audit trail" that links together all of the essential parameters of drug action, from the molecular target to the clinical effects. The pharmacological audit trail allows us to answer two absolutely crucial questions: (1) how much gets there; and (2) what does it do? During the pre-clinical drug discovery phase, it is essential that pharmacokinetic/pharmacodynamic (PK/PD) properties are optimized, so that the best candidate can be selected for clinical development. As part of contemporary mechanistic, hypothesis-testing clinical trials, construction of the pharmacological PK/PD audit trail facilitates rational decision-making. However, PK/PD endpoints frequently require invasive sampling of body fluids and tissues. Non-invasive molecular measurements, e.g. using MRI or spectroscopy, or positron emission tomography, are therefore very attractive. This review highlights the need for PK/PD endpoints in modern drug design and development, illustrates the value of PK/PD endpoints, and emphasises the importance of non-invasive molecular imaging in drug development. Examples cited include the use of PK/PD endpoints in the development of molecular therapeutic drugs such as the Hsp90 molecular chaperone inhibitor 17AAG, as well as the development of SR-4554 as a non-invasive probe for the detection of tumour hypoxia.

Tumour volume changes following pre-operative radiotherapy in borderline resectable limb and trunk soft tissue sarcoma.

AIMS: To evaluate tumour volume changes after preoperative radiotherapy (PRT) for borderline operable soft tissue sarcomas (STS). MATERIALS AND METHODS: A retrospective review was performed of 68 patients who received PRT between December 2004 and July 2011. Endpoints were radiological response, surgical margins, local control and survival. RESULTS: Median tumour size was 12.5 cm. Tumour location was extremity (87%), trunk (12%), and neck (1%). Commonest histological subtypes were myxoid liposarcoma (32%) and myxofibrosarcoma (16%). The majority of patients (88%) received 50 Gy in 25 fractions. Post-radiotherapy imaging was available in 55 cases. By RECIST there was stable disease in 89%, partial response in 7% and progressive disease in 4%. Tumour volumes reduced in 80%. Median change in maximal tumour dimension was -13.6%; median change in volume was greater, at -33.3%. Tumour volumes increased in 11 cases (20%). However, surgical margins were clear in all 11 cases, with no local recurrences in this group. For the entire group, surgical margins were clear in 93%, and microscopically positive in 7%. Eight patients (12%) had local relapse at 2-24.8 months after surgery. Two year local relapse free survival was 87.5%; 2 year overall survival was 74.7%. CONCLUSION: The majority of tumours showed reduction in volume. A small number of tumours increased in volume, but there was no definite relationship between volume increase and poor surgical outcomes or lower local control rates. Local control was equivalent to published series' of PRT. PRT is a reasonable approach in patients with borderline resectable tumours.