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W De Neve

Publications and source records attributed to W De Neve.

At least 55 records · Page 3Linked to original sources
PubMed1999

Diamond detector measurements near simulated air channels for narrow photon beams.

BACKGROUND AND PURPOSE: To evaluate the combined effect of increased photon transmission, reduced photon scatter, increased secondary electron range and loss of electronic equilibrium for narrow 6-MV beams in and around a simulated air channel. MATERIALS AND METHODS: A measuring method was developed in-house for relative dose measurements near simulated air-like/soft-tissue interfaces in an automated water phantom. A Styrofoam cylinder (density 0.03 g/cm3) of 2-cm diameter was submersed in the water phantom and irradiated with small rectangular radiation fields. The field length was fixed at 10 cm and the field widths ranged from 1 to 4 cm. The axis of the foam cylinder and the long side of the field were parallel. A water layer of 2 cm was realised upstream of the cylinder. Relative depth dose and profiles behind the foam cavity were assessed using a diamond detector with a sensitive crystal thickness of 0.21 mm located at 1 mm from the top of the encapsulation. RESULTS: The dose at central axis 1.1 mm behind the cavity was found to be 92 and 74% for a field size of 10 x 2 and 10 x 1 cm2, respectively. The highly convex dose profile of the 10 x 1-cm2 field, characterising the homogeneous case, is flattened. CONCLUSIONS: The diamond detector is an excellent choice as a detector in small photon fields with high-dose gradients as they occur near air channels, provided the orientation of the detector is appropriate. Doses near air channels are subject to significant local variations as a function of small changes of field width, and local underdosing may occur in particular cases.

Models, Structural↗
PubMed1999

Dose measurements compared with Monte Carlo simulations of narrow 6 MV multileaf collimator shaped photon beams.

Small fields where electronic equilibrium is not achieved are becoming increasingly important in clinical practice. These complex situations give rise to problems and inaccuracies in both dosimetry and analytical/empirical dose calculation, and therefore require other than conventional methods. A natural diamond detector and a Markus parallel plate ionization chamber have been selected for clinical dosimetry in 6 MV photon beams. Results of simulations using the Monte Carlo system BEAM/EGS4 to model the beam geometry have been compared with dose measurements. A modification of the existing component module for multileaf collimators (MLCs) allowed the modeling of a linear accelerator SL 25 (Elekta Oncology Systems) equipped with a MLC with curved leaf-ends. A mechanical measurement method with spacer plates and a light-field edge detection technique are described as methods to obtain geometrical data of collimator openings for application in the Monte Carlo system. Generally a good agreement is found between measurements and calculations of depth dose distributions and deviations are typically less than 1%. Calculated lateral dose profiles slightly exceed measured dose distributions near the higher level of the penumbras for a 10x2 cm2 field, but agree well with the measurements for all other cases. The simulations are also able to predict variations of output factors and ratios of output factors as a function of field width and field-offset. The Monte Carlo results demonstrate that qualitative changes in energy spectra are too small to explain these variations and that especially geometrical factors affect the output factors and depth dose curves and profiles.

Biophysical Phenomena↗
PubMed1999

Postoperative radiotherapy of paranasal sinus tumours: a challenge for intensity modulated radiotherapy.

BACKGROUND AND PURPOSE: Intensity modulated radiotherapy (IMRT) is used in our department for treatment of paranasal sinuses. We describe the methodology that was developed together with the clinical implementation, illustrated by a case report. MATERIAL AND METHODS: Patient history, treatment and short follow-up are described. An IMRT, obtained by superposition of static beam segments was implemented. Electronic portal images, compared to digitally reconstructed radiographs (DRR) were used to evaluate and adjust patient positioning. RESULTS, DISCUSSION AND CONCLUSION: IMRT is an appropriate and feasible treatment technique for head and neck cancer in anatomical regions that are difficult to treat. A high tumour dose can be combined with a good sparing of the surrounding organs at risk (OAR's).

Adenocarcinoma↗
PubMed1998

Three-dimensional dosimetry using polymer gel and magnetic resonance imaging applied to the verification of conformal radiation therapy in head-and-neck cancer.

BACKGROUND AND PURPOSE: It was our aim to investigate NMR-based BANG gel dosimetry as a three-dimensional dosimetry technique in conformal radiotherapy. MATERIALS AND METHODS: The BANG gel consisting of gelatin, water and co-monomers was first validated in a cylindrical glass flask for a single standard beam. Next, the gel contained in a human neck-shaped cast was used to verify a treatment plan for the conformal irradiation of a concave tumour in the lower neck. Magnetic resonance relaxation rate images were acquired and, based on an appropriate calibration of the gel, converted to absorbed dose distributions. The resulting maps were compared with dose distributions measured using radiographic film. RESULTS: The gel-measured dose profiles of standard beams agreed within 3% (root mean square difference) with the profiles measured with high spatial resolution by a diamond detector. For the multi-beam conformal treatment, the difference map between gel-measured and film-measured dose distributions revealed a noise component and a more systematic deviation including structural or space-coherent patterns. The mean absolute value of the difference amounted to 8%. A number of possible causes for this deviation are designated. CONCLUSIONS: Polymer gel dosimetry in combination with magnetic resonance imaging is a promising method for dosimetric verification of conformal radiotherapy.

Dose-Response Relationship, Radiation↗
PubMed1997

Non-coplanar beam intensity modulation allows large dose escalation in stage III lung cancer.

PURPOSE: To evaluate the feasibility of dose escalation in stage III non-small cell lung cancer, we compared standard coplanar (2D) with non-coplanar beam arrangements, without (3D) and with beam intensity modulation (3D-BIM). MATERIALS AND METHODS: This study was a planning effort performed on a non-selected group of 10 patients. Starting from a serial CT scan, treatment planning was performed using Sherouse's GRATIS 3D planning system. Two target volumes were defined; gross tumor volume (GTV) defined a high-dose target volume that had to receive a dose of at least 80 Gy and GTV plus the lymph node regions with >10% probability of invasion defined an intermediate-dose target volume (GTV + N). It was our intention to irradiate GTV + N up to 56 Gy or more. If the prescribed doses on GTV and GTV + N could not be reached with either the 2D or 3D technique, a 3D-BIM plan was performed. The 3D-BIM plan was a class solution involving identical gantry angles, segment arrangements and relative segment weights for all patients. Dose volume histograms for GTV, GTV + N, lung and spinal cord were calculated. Criteria for tolerance were met if no points inside the spinal cord exceeded 50 Gy and if at least 50% of the lung volume received less than 20 Gy. Under these constraints, maximal achievable doses to GTV and GTV + N were calculated. RESULTS: In all 2D plans, spinal cord was the limiting factor and the prescribed doses for GTV and GTV + N could not be reached in any patient. The non-coplanar 3D plan resulted in a satisfying solution in 4 out of 10 patients under the same constraints. In comparison with 2D, the minimum dose in GTV + N was increased. Six patients had to be planned with the 3D-BIM technique. The theoretical minimum dose to GTV + N ranged between 56 and 98 Gy. The delivery of 80 Gy or more to GTV was possible in all patients. For a minimal dose of 80 Gy to GTV, the maximal dose to any point of the spinal cord varied between 27 and 46 Gy. The lung volume receiving more than 20 Gy ranged from 26 to 46%. CONCLUSION: The potential of 3D-BIM for dose escalation is explained as follows: (i) compared to other planning techniques, a larger amount of lung tissue can be spared by using beam directions that are well-aligned with the mediastinal structures. Such beam directions have narrow angles with the sagittal plane; (ii) dividing all beams into segments with well-specified geometrical restrictions in relation to the spinal cord and well-defined relative weights results in a lower dose to the spinal cord.

Carcinoma, Non-Small-Cell Lung↗
PubMed1996

Implementation, uptime, and safety of a pulsed dose rate afterloading machine.

PURPOSE: To review the routine use of pulsed dose rate brachytherapy (PDR) for replacement of low dose rate manual afterloading using classical dose rates and hourly pulses. Uptime (actual treatement time vs. planned time) and safety (dose to personnel, machine safety) of 110 implants in 101 patients were evaluated during the period from August 10, 1993 to December 27, 1994. METHODS AND MATERIALS: This study includes 80 implants in gynecological tumors; 12 for sarcoma and 6 each for bronchus, gastrointestinal, and head and neck tumors. Thirty-seven of these implants were in 14 patients with a recurrence in previously irradiated areas. In 15 patients brachytherapy was the only treatment. All pulses were given hourly, and the median dose rate at specification points was 0.6 Gy (0.4 to 3 Gy). The total number of pulses per treatment varied from 3 to 120. RESULTS: After an initial period of machine-related problems, all treatments were supported well in all but one patient and could generally be given within 5 min of the planned time although the room was entered at a mean interval of 79 min. Whenever a problem that could interfere with proper machine function is detected, a message (status code) is generated. A median of one status code (range: 0 to 24) occurred during a single implant. Status codes were caused by an open door when a pulse had to be given (44%) or related to difficulty of movement of the check cable/source through plastic tubes (34%); the remaining status codes were due to a variety of causes. The dose received by the personnel decreased almost ninefold as compared to the period when permanent implants were used. CONCLUSIONS: We find PDR at hourly pulses to be feasible, safe, and both staff- and patient-friendly. For evaluation of the clinical results longer follow-up is needed.

Adolescent↗
PubMed1996

Dynamic radiotherapy: interactive movement of patient couch for treatment of craniospinal axis.

PURPOSE: The various techniques that have been described for treatment of the craniospinal axis show the common challenge of edge matching between adjacent orthogonal and parallel photon beams. Such edge matching is needed because the maximum field length provided by modern treatment machines is generally insufficient to treat adults with less than three matching fields. Using the common techniques, field edge matching becomes difficult, if for medical reasons, the patient cannot be treated in the prone position. METHODS AND MATERIALS: A scanning couch technique is proposed, with the patient lying in supine position. After treating the cerebral and upper neck regions by two lateral opposed half beam fields defined by asymmetric collimators (split beam), the patient is being moved along the spinal axis through an 8.0 cm wide by 15.0 cm long posterior split beam (allowing edge matching with the lateral fields at the neck region) by means of remote controlled couch movement. Stopping and starting of the scanning field resulted in a linear decrease of dose on both sides of the scan. Two ways of resolving this problem were investigated. RESULTS: The administered dose varied less than 8.5% through the craniospinal axis. Flatness of the rectangular scanned field was 0.76%. Apart from dose homogeneity, patient comfort and decreased simulation time are major advantages. CONCLUSIONS: The proposed technique represents a suitable alternative using a common linear accelerator, requiring a remote couch controller as an additional component.

Adult↗
PubMed1996

Planning and delivering high doses to targets surrounding the spinal cord at the lower neck and upper mediastinal levels: static beam-segmentation technique executed with a multileaf collimator.

BACKGROUND AND PURPOSE: It remains a technical challenge to limit the dose to the spinal cord below tolerance if, in head and neck or thyroid cancer, the planning target volume reaches to a level below the shoulders. In order to avoid these dose limitations, we developed a standard plan involving Beam Intensity Modulation (BIM) executed by a static technique of beam segmentation. In this standard plan, many machine parameters (gantry angles, couch position, relative beam and segment weights) as well as the beam segmentation rules were identical for all patients. MATERIALS AND METHODS: The standard plan involved: the use of static beams with a single isocenter; BIM by field segmentation executable with a standard Philips multileaf collimator; virtual simulation and dose computation on a general 3D-planning system (Sherouse's GRATIS); heuristic computation of segment intensities and optimization (improving the dose distribution and reducing the execution time) by human intelligence. The standard plan used 20 segments spread over 8 gantry angles plus 2 non-segmented wedged beams (2 gantry angles). RESULTS: The dose that could be achieved at the lowest target voxel, without exceeding tolerance of the spinal cord (50 Gy at highest voxel) was 70-80 Gy. The in-target 3D dose-inhomogeneity was approximately 25%. The shortest time of execution of a treatment (22 segments) on a patient (unpublished) was 25 min. CONCLUSIONS: A heuristic model has been developed and investigated to obtain a 3D concave dose distribution applicable to irradiate targets in the lower neck and upper mediastinal regions. The technique spares efficiently the spinal cord and allows the delivery of higher target doses than with conventional techniques. It can be planned as a standard plan using conventional 3D-planning technology. The routine clinical implementation is performed with commercially available equipment, however, at the expense of extended execution times.

Dose-Response Relationship, Radiation↗
PubMed1996

Primary gastric non-Hodgkin's lymphoma stage IE and IIE.

The aim of this study was to evaluate retrospectively the different treatment approaches and outcome of patients with stage IE and IIE gastric non-Hodgkin's lymphoma in a cancer registry. Between 1982 and 1992, the Comprehensive Cancer Centre South (CCCS), Eastern Section, The Netherlands, registered, in a population of 1 million people, a total of 81 cases of gastric lymphoma stage IE and IIE (43 men and 38 women). Median age was 69.7 years (range 30.4-88.1). According to the Working Formulation, the malignancy grade was: 9 low, 55 intermediate and 14 high. According to the MALT classification, the malignancy grade was: 38 low and 40 high. Grade was unknown in 3 patients. Patients received the following treatment modalities: surgery alone (n = 22), locoregional radiotherapy without (n = 12) or with (n = 13) surgery; or systemic chemotherapy alone (n = 10) or with radiotherapy and/or surgery (n = 18). No treatment was given or recorded in 6 patients. For stage IE, 5-year actuarial survival and relapse-free survival rates were, respectively, 76 and 64% in 18 patients who received only surgery; 70 and 67% in 17 patients given locoregional treatment (radiotherapy with or without surgery), and 76 and 62% in 13 patients given systemic treatment (chemotherapy alone or with radiotherapy and/or surgery). Radiotherapy as sole treatment seemed to be as effective as other treatment modalities in achieving local and abdominal control. For stage IIE, none of the 4 patients who were treated with surgery alone survived 5 years. The 5-year actuarial survival and relapse-free survival rates of 8 patients who received radiotherapy with or without surgery were, respectively, 25 and 17% and 49 and 33%, for 14 patients given systemic therapy (chemotherapy alone and/or radiotherapy/surgery). In stage IIE, local, abdominal as well as distant relapse were more common, irrespective of treatment modality. In the multivariate analyses, stage (P = 0.002), grade (P = 0.02), age (P = 0.04) and gender (P = 0.04) were significant prognostic factors. This report on a limited number of patients shows that the outcome of patients with stage IIE gastric lymphoma is much worse than for patients with stage IE. Grade, age, gender and particularly stage are much stronger indicators for survival than different modes of treatment. Systemic therapy might improve outcome for stage IIE, but not for stage IE, for which radiotherapy alone seems a good option.

Adult↗
PubMed1995

Clinical implementation of an objective computer-aided protocol for intervention in intra-treatment correction using electronic portal imaging.

In order to test the feasibility of a protocol for intra-fractional adjustment of the patient position, during radiation therapy treatment in the pelvic region, a two-fold study is carried out. The protocol involves an objective quantitative measurement of the error in positioning starting from the comparison of a portal image with a reference image. The first part of the study applies the protocol to determine the efficacy of adjustment using subjective determination of the positioning errors by a clinician by measuring the residual errors after adjustment. A group of 13 patients was followed extensively throughout their treatment, analyzing 240 fields. In the second part the measurement itself determines the extent of readjustment of the position. Throughout the procedure elapsed time is measured to determine the extra time involved in using this procedure. For this part a group of 21 patients was followed yielding statistics on 218 fields. Using this computer aided protocol it is shown that systematic as well as random errors can be reduced to standard deviations of the order of 1 mm. The price to pay however is additional treatment time up to 58% of the treatment time without the protocol. Time analysis shows that the largest part of the added time is spent on the readjustment of the patients' position adding a mean of 37% of time to the treatment of one field. This is despite the fact that the readjustment was performed using a remote couch controller. Finally a statistical analysis shows that it is possible to select patients benefiting from the use of such a protocol after a limited number of fractions.

Feasibility Studies↗
PubMed1995

Radiotherapy for T2 and T3 carcinoma of the bladder: the influence of overall treatment time.

The influence of overall treatment time on local control rate was studied on a group of 147 patients with muscle invasive T2 or T3 transitional cell carcinoma of the urinary bladder. All patients received external radiotherapy at the Catharina Hospital, Eindhoven, The Netherlands between January 1974 and December 1984. Patients treated with overall treatment times shorter than 75 days (n = 92) were irradiated during a continuous course; all but one patient, with overall treatment times of 75 days or more (n = 55), received split-course radiotherapy. Actuarial local relapse-free probability at 3 years (LRFP3) was computed from the onset of radiotherapy. LRFP3 proved to be dependent on overall treatment time. For T2 stage, LRFP3 was 80 +/- 18% (n = 5) and 54 +/- 13% (n = 13) for overall times between 15-44 and 45-74 days, respectively, 36 +/- 14% (n = 11) for overall times between 75 and 104 days and 64 +/- 15% (n = 11) for overall times longer than 105 days. For T3 stage, LRFP3 was 33 +/- 19% (n = 6) and 48 +/- 10% (n = 25) for overall times between 15-44 and 45-74 days, respectively, 25 +/- 14% (n = 12) for overall times between 75 and 104 days and 22 +/- 14% (n = 9) for overall times longer than 105 days. The figures between brackets are numbers of patients relapsing within 3 years or at risk of relapse during at least 3 years. Patients who died without local relapse before 3 years were censored. We have reasons to believe that patient selection bias leads to overestimation of LRFP3 for the split-course radiotherapy in retrospective studies where the 'intention to treat' cannot be recalled. This retrospective study suggests that prolonging overall time of radiotherapy has an effect on local control in T2 and T3 transitional cell carcinoma of the urinary bladder. Local control was the worst for patients treated by split-course radiotherapy with a gap of approximately one month. Local control was not further decreased (and seemed even improved) by longer gaps, but this observation is possibly biased as explained in the discussion section. For patients treated by continuous course radiotherapy we could not find a difference in local control rates between patients treated with overall times of 44 days or less and those treated with overall times of 45-74 days.

Adult↗
PubMed1995

Prognostic factors in locoregional non-small cell lung cancer treated with radiotherapy.

By means of a retrospective study an evaluation was made of prognostic factors on survival in patients with inoperable locoregional non-small cell lung cancer. The study was performed on a group of 239 patients with a median age of 69 years, 225 men, and 14 women. Patients were treated with external radiotherapy without (184) or with (55) chemotherapy. They received either continuous-course radiotherapy (5,500 cGy in 27-28 fractions and 5.5 weeks) or split-course radiotherapy (1 series of 3,000 cGy, 2 series of respectively 3,000 cGy and 2,500 cGy, or 3 series of, respectively 3,000 cGy, 2,500 cGy, and 2,000 cGy; each series in 10 fractions and 2 weeks, separated by a 4-week interval). Univariate analysis was done by life-table analysis and log-rank test, multivariate analysis by the Cox Proportional Hazards model. The overall survival at 1, 2, and 3 years was 36%, 11%, and 4%. Survival was not significantly influenced by localization of the tumor, grading, distance to the carina, growth pattern, diameter, partial or total atelectasis, lymph node invasion or stage. No significant difference in survival was found between patients who received only radiotherapy and those treated with a combination of radiotherapy and chemotherapy. Univariate analysis showed significant better survival in patients with squamous cell epithelioma, patients without pleural effusion, patients younger than 75 years and patients receiving higher radiation doses. Multivariate analysis showed dose of radiation (P < .001) and pleural effusion (P = .03) to be independent prognostic factors.

Adult↗
PubMed1995

Prosthesis for the treatment of metastatic bone disease of the hip: effects of radiotherapy.

Twenty-eight patients with metastatic involvement of the proximal femur were all treated by resection and prosthetic replacement. A large femoral prosthetic component was routinely fixed with polymethylmetacrylate bone cement. Local radiotherapy was delivered preoperatively in two patients and postoperatively in seven patients. Postoperative pain relief according to Habermann et al off excellent in 81% and good in 15% of the patients. The functional results according to the hip-rating scale of Merle d'Aubigné were rated as excellent in 19%, very good in 22% and good in 22% of the hips. The prognosis for survival was superior in those patients with a preoperative Karnofsky performance status index of more than 60 points (p < 0.01) and in those patients without postoperative pulmonary complications (p < 0.01). The radiographs of the eighteen patients surviving three months or longer showed formation of a new bony envelope around the femoral prosthetic component in 11 cases (61%) and bone remodelling of the distal femur in 12 cases (67%). When analyzed according to local radiotherapy these radiographic changes occurred only if no local radiotherapy had been delivered to the femur (p < 0.01).

Activities of Daily Living↗
PubMed1994

On the determination of the effective transmission factor for stainless steel ovoid shielding segments and estimation of their shielding efficacy for the clinical situation.

Commercially available ovoid tubes for gynecological applications used in conjunction with the microSelectron-HDR (Nucletron International B.V., Waardegelder 1, 3905 TH Veenendaal, The Netherlands) for 192Ir sources, allow for shielding. Publications concerning the transmission properties of these 4.5-mm thick stainless steel (AISI number 303/304) shielding segments are scarce and not compatible for implementation in treatment planning. Therefore the effect of shielding on dose distribution is unknown. The effective transmission factor has been measured and implemented in the planning computations. Screening efficacy was evaluated on 20 actual treatment plans, analyzing dose reduction to critical tissue and comparing dose distribution in planes relevant for this particular application. Due to high transmission (effective transmission factor = 0.85), stainless steel screening segments only provide low, local dose reductions of maximum 15%. A new approach with regard to optimization and source configuration is needed to reduce dose to vulnerable tissue, exploiting the screening segments to a maximum extent. Better shielding, especially at the midline (plane bisecting the ovoids) could be expected by using shielding segments with other geometrical characteristics.

Biophysical Phenomena↗
PubMed1994

[Prosthetic replacement for pathological fractures of the proximal end of the femur: total prosthesis or bipolar arthroplasty?].

INTRODUCTION: The purpose of this prospective study was to present our experience with bipolar or total hip arthroplasty in 28 consecutive cases of metastasis of the intertrochanteric and subtrochanteric area. MATERIALS AND METHODS: Twenty-eight patients with metastatic involvement of the proximal femur underwent either bipolar or total hip arthroplasty. Proximal femoral resection and prosthetic replacement with a massive component was routinely performed. RESULTS: The postoperative morbidity rates for dislocation and pressure sores were significantly lower (p < 0.05) in the bipolar arthroplasty group. Postoperative pain relief according to Habermann was excellent in 81.5 per cent and good in 14.8 per cent of the patients. The functional results according to the hip rating scale of Merle d'Aubigné were rated as excellent in 19 per cent, very good in 22 per cent and good in 22 per cent of the hips. The prognosis for survival was superior in patients with a preoperative Karnofsky performance status index of more than 60 points (p < 0.01) and in patients without postoperative pulmonary complications (p < 0.01). New bone formation around the femoral prosthetic component occurred in 11 (61 per cent) of the 18 patients surviving three months or longer. This bone formation did not affect the clinical results. In the current series pain relief as well as postoperative walking ability were comparable in both groups but the dislocation rate was significantly lower (p < 0.05) with bipolar arthroplasty. CONCLUSION: We recommend bipolar arthroplasty rather than total hip arthroplasty in patients with a preoperative Karnofsky performance status index of more than 60 points if bone disease of the acetabulum is not evident on standard radiographs and if during operation the acetabular cartilage appears normal.

Adult↗
PubMed1994

Effect of irradiation on hepatic natural killer cells.

The rat liver contains a population of natural killer cells consisting of two morphologically and functionally different subsets, a low-density and a high-density fraction. In this work we describe the influence of low-dose radiation on hepatic natural killer activity. The effect on the cytotoxicity against YAC-1 lymphoma and CC531 colon adenocarcinoma tumor cells was measured in chromium-51 assays, and morphological changes were analyzed by means of electron microscopy. The low-density natural killer fraction showed increased cytotoxicity against YAC-1 which was associated with an increased binding of natural killer cells to the YAC-1 tumor cells shortly after irradiation. These phenomena were paralleled by an increased number of multivesicular bodies and cytoplasmic granules with an electron-lucent halo. In contrast, the other hepatic natural killer cell fraction, the high-density natural killer cells, did not show increased cytotoxicity, binding or morphological alterations. The radiation-stimulated lysis of YAC-1 cells was also observed when in vivo irradiated cells were isolated and tested immediately for in vitro lysis of YAC-1 cells. Sixteen hours after in vitro or in vivo irradiation, the cytotoxicity of hepatic natural killer cells against YAC-1 was no longer enhanced. The cytolysis of and binding of hepatic natural killer cells to CC531 colon adenocarcinoma cells was not stimulated by in vitro irradiation. From these experiments, we conclude that low-dose radiation stimulates the cytotoxicity of hepatic low-density natural killer cells against YAC-1 lymphoma cells immediately after irradiation as the result of enhanced binding of the cells to the tumor cells, in addition to the synthesis of new cytotoxic granules.

Adenocarcinoma↗