Simulated surgery on computed tomography and magnetic resonance images: an aid for intraoperative radiotherapy

Intraoperative radiotherapy (IORT) is a relatively new technique in which irradiation with electrons is performed during an open surgery procedure. This approach poses significant problems in obtaining accurate dosimetry, since neither the pre- nor the postoperative patient images actually matches the irradiation field. Our objective was to implement a software tool able to provide an estimate of the dose distribution, overcoming the problem of the geometrical mismatch between the images and the surgical field during the irradiation. The program was developed in the C programming language, on a noncommercial version of a Philips EasyVision workstation. The application allows to create a new data set by manipulating the preoperative computed tomography and magnetic resonance images in order to simulate the final geometry of the surgical area during the IORT procedure. The exact dose distribution can then be calculated by transferring these new images to a standard radiotherapy planning system. Also an approximate dose distribution can be quickly displayed by superimposing isodose curves obtained from a water phantom. The proposed approach introduces a helpful tool for dosimetry and planning in IORT protocols, improving their accuracy and safety and allowing for more objective quality control and patient follow-up.

[Intraoperative radiotherapy with accelerated electrons for urinary bladder carcinoma: principles and results]

OBJECTIVE

To describe intraoperative radiotherapy with accelerated electrons, a highly selective method of administering irradiation for radical treatment of bladder cancer.

METHODS

We reviewed the experience reported in the literature since this treatment modality was utilized in Japan and its application extended to the western countries.

RESULTS

Animal experiments have shown an acceptable clinicopathological tolerance to 20 Gy intraoperative irradiation of partial bladder volume. The local recurrence rate was 9% for early solitary tumor (> T2) and 27% for early multicentric tumor, according to the Japanese clinical experience. In the western countries, intraoperative radiotherapy plus external irradiation with or without systemic chemotherapy achieves a pT0 of about 65% (in total cystectomy specimens) and an intravesical tumor control rate of 88% in organ-sparing protocols.

CONCLUSIONS

The results achieved by the groups with wider experience demonstrate that highly selective intraoperative radiotherapy is feasible, well-tolerated and effective in terms of inducing complete pathological remissions and definitive control of intravesical tumor. These selected clinical experiences must be corroborated by multicenter studies.

Innovative techniques in modern radiation oncology: the economic and organizational impact

An overview of the impact of innovative techniques in modern radiotherapy on economic and organizational issues is proposed. The analyzed innovative procedures are: intraoperative radiotherapy, stereotactic radiosurgery, conformal radiotherapy and high dose rate brachytherapy. They are approached separately in terms of cost-benefit analysis, optimized management and estimated productivity. The introduction of these innovative techniques in the daily practice of radiation oncology departments is vital in the quest for excellence. The strictly monetary implications of programs for the implementation of innovative radiotherapy techniques are hindered by the present planned containment of public health care expenditure in western European countries.

Self-administered joint counts in rheumatoid arthritis: comparison with standard joint counts

OBJECTIVE

To test the reliability and validity of a self-administered 36 joint count developed after the Rapid Assessment of Disease Activity in Rheumatology (RADAR) questionnaire for assessing pain/tenderness.

METHODS

Two self-administered formats (mannequin and text) were evaluated in 60 patients with rheumatoid arthritis (RA). Reliability between both formats was tested by Spearman rank correlation. Criterion validity/accuracy was tested by Spearman correlation coefficient between each self-report format and a joint count performed by a physician. Construct validity was ascertained by correlation of each format with other variables of disease activity.

RESULTS

Reliability between the 2 formats was high (R = 0.94). Correlations between each format and the physician's joint count were also high (R = 0.77 for mannequin, 0.75 for text). Patients consistently rated their joint pain/tenderness higher than the physician (means 29, 27, and 12 for text, mannequin, and physician, respectively; p < 0.01). Construct validity of the text, mannequin, and physician formats compared with the modified Health Assessment Questionnaire showed R = 0.61, 0.65, 0.63; with Steinbrocker functional class R = 0.41, 0.46, 0.56; with pain R = 0.59, 0.61, 0.62; with global evaluation R = 0.66, 0.71, 0.84; and with morning stiffness R = 0.64, 0.59, 0.60, respectively.

CONCLUSION

Although both self-administered formats exhibited adequate reliability and construct validity, a systematic difference between patient and physician/trained assistant performed joint counts was observed, with patients consistently rating their pain/tenderness higher. We thus do not believe they can replace standard physician/trained assistant evaluation in obtaining clinical research data in rheumatology.

Intraoperative radiotherapy. Literature updating with an overview of results presented at the 6th International Symposium of Intraoperative Radiation Therapy

Intraoperative radiotherapy is a technique that can be integrated into multidisciplinary treatment strategies in oncology. A radiation boost delivered with high energy electron beams can intensify locoregional antitumor therapy in patients undergoing cancer surgery. Intraoperative radiotherapy can increase the therapeutic index of the conventional combination of surgery and radiotherapy by improving the precision of radiation dose location, while decreasing the normal tissue damage in mobile structures and enhancing the biological effect of radiation when combined with surgical debulking. Intraoperative radiotherapy has been extensively investigated in clinical oncology in the last 15 years. Commercially available linear accelerators require minimal changes to be suitable for intraoperative radiotherapy. Its successful implementation in clinical protocols depends on the support given by the single institutions and on a clinical research-oriented mentality. Tumors where intraoperative radiotherapy as a treatment component has shown promising rates of local control include locally advanced rectal, gastric and gynecologic cancer, bone and soft tissue sarcoma. Intraoperative radiotherapy can be applied to brain tumors, head and neck cancer, NSCLC and pancreatic carcinoma.

Stereotactic radiosurgery with linear accelerator

Stereotactic radiosurgery is a method that applies a radiation dose to a limited and well-defined volume while the irradiation of adjacent healthy tissues is minimized. It is most commonly used in the treatment of intracranial lesions because the skull hardness assures the stable location of its contents. Treatment of the rest of the body has recently been proposed and carried out, using original immobilization systems. Stereotactic radiosurgery was first described in 1951 by the Swedish neurosurgeon Lars Leksell who originally used X-rays and then high-energy protons as a source of radiation. In the '80s photons from linear accelerators were used as radiation source, with various stereotactic systems and computerized treatment planning. The method used with all radiosurgical systems, regardless of the source of irradiation, is similar. The lesion is detected with common diagnostic imaging and adequate location frames. At present, to prevent errors in location, MRI and CT data are matched using an Image Fusion computer program. The objective of stereotactic radiosurgery is to destroy tumor cells or to induce changes in tissues that, as in brain arteriovenous malformations lead to the occlusion of their abnormal vessels. Stereotactic radiosurgery is increasingly used today in the treatment of a variety of intracranial lesions to the patients' benefit.

Patterns of failure and long-term results in high-risk resected gastric cancer treated with postoperative radiotherapy with or without intraoperative electron boost

BACKGROUND

To evaluate the possible role of adjuvant radiotherapy in the management of high-risk resected gastric carcinoma.

METHODS

From 1982 to 1993, 62 patients surgically resected of a primary gastric cancer with adverse pathological features (serosal and/or regional lymph node involvement) were treated with postoperative radiotherapy with (Group I) or without (Group II) intraoperative electron boost to the surgical bed and coeliac axis (IORT).

RESULTS

After a median follow-up of 75.6 months (range 4-120+) for IORT patients and 91.2 months (range 6-149+) for non-IORT patients, overall relapse rates for Group I and Group II patients were 44.5% and 48.6% and local-regional relapse rates were 11.1% and 20%, respectively. Actuarial survival rates projected at the maximum follow-up were 41% and 38% in Groups I and II, respectively.

CONCLUSIONS

This retrospective analysis suggests a beneficial effect of adjuvant external radiotherapy in promoting local-regional control in high-risk resected gastric cancer.

Patterns of failure and long-term results in high-risk resected gastric cancer treated with postoperative radiotherapy with or without intraoperative electron boost

BACKGROUND

To evaluate the possible role of adjuvant radiotherapy in the management of high-risk resected gastric carcinoma.

METHODS

From 1982 to 1993, 62 patients surgically resected of a primary gastric cancer with adverse pathological features (serosal and/or regional lymph node involvement) were treated with postoperative radiotherapy with (Group I) or without (Group II) intraoperative electron boost to the surgical bed and coeliac axis (IORT).

RESULTS

After a median follow-up of 75.6 months (range 4-120+) for IORT patients and 91.2 months (range 6-149+) for non-IORT patients, overall relapse rates for Group I and Group II patients were 44.5% and 48.6% and local-regional relapse rates were 11.1% and 20%, respectively. Actuarial survival rates projected at the maximum follow-up were 41% and 38% in Groups I and II, respectively.

CONCLUSIONS

This retrospective analysis suggests a beneficial effect of adjuvant external radiotherapy in promoting local-regional control in high-risk resected gastric cancer.

Preoperative chemoradiation and adjuvant surgery in locally advanced or recurrent cervical carcinoma

From February 1988 to May 1994, 31 patients (pts) with the established diagnosis of locally advanced (IB-IIA bulky,IIB,III,IVA) or recurrent cervical carcinoma were treated with simultaneous chemotherapy (CT) and external beam radiotherapy (RT) followed by radical surgery (RS) with or without intraoperative radiation therapy boost (IORT) to the high risk areas for recurrence. CT consisted of cisplatin 20 mg/m2 and 5-Flourouracil 1000 mg/m2 (maximum dose 1500 mg) in a 24-hour continuous IV infusion for 3-5 days during the first and fifth weeks of the scheduled course of RT. RT was delivered with standard fractionation up to a 40-46 Gy total dose. RS was performed 4-6 weeks later. Pathologic findings revealed complete and quasi-complete response (pCR+qpCR) in 74% of the surgical specimens and partial response (pPR) in 26%. With a median follow-up of 27+ months (3-71+), actuarial disease-free survival is 80% (91.3% for pCR+qpCR, 40% for pPR). Loco-regional control rate is 93.4%. The concurrent administration of RT and CT has moderate toxicity and can promote a high rate of pCR+qpCR as well as local control in high risk cervical carcinoma. The presence of a pCR or qpCR specimen seems to be correlated with good patient outcome.

Intraoperative radiation therapy in malignant glioma: early clinical results

Intraoperative radiation therapy (IORT) with high energy electron beams is a treatment modality that has been included in multimodal programs in oncology to improve local tumor control. From August 1991 to December 1993, 17 patients with primary (8) or recurrent (9) high grade malignant gliomas, anaplastic astrocytoma (4), anaplastic oligodendroglioma (6) and glioblastoma multiforme (7), underwent surgical resection and a single dose of 10-20 Gy intraoperative radiation therapy was delivered in tumor bed. Fourteen patients received either pre-operative (8) or post-operative (6) external beam radiation therapy. Primary gliomas: 18-months actuarial survival rate has been 56% (range: 1-21+ months) and the median survival time has not yet been achieved. Four patients developed tumor progression (median time to tumor progression: 9 months). Recurrent gliomas: 18-months actuarial survival rate and median survival time has been 47% and 13 months (range: 6-32+ months) respectively. The median time to tumor progression was 11 months. No IORT related mortality has been observed. IORT is an attractive, tolerable and feasible treatment modality as antitumoral intensification procedure in high grade malignant gliomas.

Intraoperative radiotherapy in recurrent gynecological cancer

A retrospective analysis to assess the feasibility and clinical tolerance of intraoperative radiotherapy (IORT) in the treatment of recurrent gynecologic cancer is reported. From February 1985 to September 1992, 26 patients with recurrent gynecologic tumors entered this trial. The clinical experience comprises two different categories of disease situations: tumors relapsing after full dose radiation therapy (group I) and recurrent disease to previous surgery (group II). Cervical carcinoma was the initial tumor site of involvement in 18 patients (69%). Treatment consisted in maximal surgical resection + IORT boost (10-25 Gy) to the high-risk areas for recurrence. Non previously irradiated patients also received external beam irradiation (EBRT) (+/- chemotherapy) pre- or postoperatively. IORT-related toxicity was one episode of motor neuropathy. Local control rates have been 33% and 77%, respectively in groups I and II. The 4-year actuarial overall survival in Group I is 7% and 6-year actuarial overall survival in Group II is 33%. The addition of IORT to surgical debulking achieves modest local control and long-term survival rates if tumor-free margins cannot be obtained in previously irradiated patients. Combined EBRT (+/- chemotherapy) maximal surgical resection plus IORT could render some long-term survivors among those surgical recurrent patients not candidates for radical surgery with curative intent.

Intraoperative radiotherapy in locally advanced recurrent colorectal cancer

PURPOSE

In an effort to promote local control and improve quality of life in patients with recurrent colorectal cancer, a multimodality approach has been used.

METHODS AND MATERIALS

Twenty-seven patients were treated with moderate doses of pre/postoperative radiotherapy with/without simultaneous systemic chemotherapy, surgical re-resection and IORT electron boost over areas at high risk for local recurrence.

RESULTS

The 2-year actuarial disease-free and local relapse-free survival for the entire group were 14% and 26%, respectively. The most important factor predicting a favorable outcome was the radicality of surgical procedure. The determinate local control rate and the actuarial 2-year local relapse-free, and disease-free survival for patients undergoing complete resections were 50%, 56%, and 34%, respectively, whereas for patients undergoing partial resections these figures were 16%, 13%, and 6%. The radicality of surgical procedure was influenced by both tumoral size and previous treatment with irradiation. Complete resection rate was higher in patients with tumors less than 5 cm vs. more than 5 cm (40% vs. 22%), and in patients without previous radiotherapy versus those with previous radiotherapy (40% vs. 28%). Distant metastasis rate was high (41%). The most significant toxicities attributable to the whole treatment protocol were enteritis (37%), hydronephrosis (30%), and pelvic neuropathy (52%).

CONCLUSION

Currently, our policy is to recommend IORT in patients with "favorable factors" such as: absence of previous pelvic radiotherapy, single previous surgical procedure, and complete resections.

New advances in radiation oncology for gynecologic cancer

In 1992, the American Cancer Society anticipates that there will be 1,130,000 new cases of invasive cancer diagnosed in the United States. About 66,500 will be invasive cancers of the cervix, uterus, and ovary. About 22,400 patients will die during 1992, with 50-60% of those deaths being due to persistent local regional disease. Data are available to suggest that a reduction in local failure will be reflected by an increase in survival free of disease. In 1992, major efforts are being made to reduce the incidence of local failure. Three areas in this regard are innovative uses of brachytherapy, intraarterial chemotherapy and radiation therapy, and continuous infusion chemotherapy and radiation therapy. These new techniques show significant reduction in local failure with associated improvement in survival. The data will be presented to illustrate the impact of these techniques.

Intraoperative and external preoperative radiotherapy in invasive bladder cancer: effect of neoadjuvant chemotherapy in tumor downstaging

Absence of residual cancer (pT0) in the cystectomy specimen was evaluated in patients with invasive bladder cancer treated with intraoperative (IORT) (15 Gy) and preoperative external beam radiotherapy (EBR) (46 Gy/5 weeks) with or without neoadjuvant chemotherapy. The overall pT0 rate was 68% (67% and 70% in patients with or without neoadjuvant chemotherapy, respectively). The tolerance to the program was acceptable in both groups. It is concluded that intense, combined modality treatment is feasible in bladder cancer patients, and the addition of neoadjuvant chemotherapy does not increase the morbidity. Preliminary results on disease-free survival are encouraging.

Urokinase combination chemotherapy in small cell lung cancer. A phase II study

BACKGROUND AND METHODS

Fifty-one patients with small cell lung cancer (SCLC) were treated with alternating urokinase (UK)-cyclophosphamide-doxorubicin (Adriamycin, Adria Laboratories, Columbus, OH)-vincristine and cisplatin-etoposide-vincristine. UK was given as a loading dose of 3000 micrograms/kg body weight, followed by 3000 micrograms/kg/h for 6 hours. Thoracic irradiation with split technique (46 Gy) and prophylactic cranial irradiation (25 Gy) were administered to responding patients. A second staging was performed in patients exhibiting a clinical complete response (CR) after 1 year.

RESULTS

In 27 patients with limited disease, there were 23 CR and 8 partial responses (PR) (CR, 85.1%; 66.2-95.8% at 95% confidence intervals); in 24 patients with extensive disease, there were 17 CR, 4 PR, and 3 cases with progression. Pathologically proven CR were observed in 59.2% patients with limited disease and 33.3% patients with extensive disease. Survival rates were as follows: in patients with limited disease, 1 year, 85.1%; 2 years, 55.5%; and 3 years, 25.9%; in patients with extensive disease, 1 year, 54.1; and 2 years, 16.9%. Median survival times were 26.3 months (patients with limited disease) and 13.3 months (patients with extensive disease). UK-related toxic effects included four episodes of mild to moderate bleeding, one allergic reaction, and one cerebrovascular accident. Myelotoxicity was severe, with a median of two episodes of Grade III-IV (World Health Organization classification) aplasia per patient.

CONCLUSIONS

These results are consistent with a potential benefit of fibrinolytic therapy in combination with chemotherapy in patients with SCLC with limited disease. Additional trials are indicated.

Clinical trials with anticoagulant and antiplatelet therapies

Clinical trials of drugs that influence coagulation and fibrinolysis pathways have been undertaken in patients with malignancy because these pathways are capable of influencing malignant progression. The validity of this concept was originally confirmed in experimental animal models of malignancy. Earlier pilot studies in human disease have been succeeded by definitive prospective randomized clinical trials that have revealed heterogeneity of responsiveness to anticoagulant and fibrinolytic agents that may be attributable to differences in mechanisms of interaction of the tumor cells of various types of malignancy with these pathways in vivo. In certain tumor types studied thus far, increased tumor response rates and prolongation of survival have been observed that suggest the possibility that substantial benefit may be realized from this treatment approach in patients with malignancy. In addition, the availability of newer and potentially more effective therapeutic agents holds promise for even greater gains in previously tested tumor types. The ability to design treatment regimens that correspond to defined mechanisms that pertain to specific tumor types should permit future studies to be designed rationally. Current data suggest that anticoagulant and fibrinolytic agents might reasonably be tested in tumor types characterized by the existence of a tumor cell-associated coagulation pathway with thrombin generation and conversion of fibrinogen to fibrin (such as small cell carcinoma of the lung). By contrast, protease inhibitors might reasonably be tested in tumor types characterized by expression of tumor cell plasminogen activators. Expansion of current views on the possible role of antithrombic drugs in cancer therapy is justified. For example, antithrombotic drugs classified as non-steroidal anti-inflammatory agents may inhibit carcinogenesis while polyanionic drugs with anticoagulant properties, such as suramin and heparin, may inhibit growth factor interactions with cells. Intriguing new opportunities clearly exist for interactions between clinical and basic investigators that may provide both novel biologic insights and improved patient care.

[Infiltrating carcinoma of the bladder: preliminary results of multidisciplinary protocols with radiotherapy and neoadjuvant chemotherapy]

Report on the evolution of a series of 64 patients with T2-4 N0-3 M0 infiltrant transitional carcinoma of the bladder, treated with TUR and radical cystectomy (28/62) or intra-operative radiotherapy (IOR) 15 Gy and external radiotherapy 40 Gy prior to cystectomy (34/62). The last group including 24 patients which received neo-adjuvant chemotherapy. Seventy percent (15 p0N-, 5 p0N+, 1 p1N-, 3 p1N+) patients treated with radiotherapy, with and without chemotherapy, had local response. Considering just the group which received IOR, external radiotherapy and co-adjuvant chemotherapy (24/34), the local response accounts for 79% (10 p0N-, 5 p0N+, 1 p1N-, 3 p1N+). Current survival of the group receiving concomitant multiple therapy is 92 +/- 5%, 75 +/- 9% and 57 +/- 11% at 1, 3 and 5 years; for equal intervals current survival of the group undergoing cystectomy is 57 +/- 9%, 46 +/- 9% and 40 +/- 10% (p = 0.02). The univariate analysis has confirmed that stage decrease is significantly more frequent in the group receiving radiotherapy with and without chemotherapy (p less than 0.001). Such a decrease significantly biased survival (p = 0.001). In the multivariate analysis, the variables with greater prognostic power were pre-surgical renal function (p less than 0.001), use of radiotherapy (p less than 0.001) and surgical complications (p less than 0.001). Preliminary results show a very high local response to multiple therapy which has been translated so far in increased survival.

Intraoperative and external radiotherapy in resected gastric cancer: updated report of a phase II trial

From September 1984 to August 1991, 48 evaluable patients with resected gastric cancer and apparent disease confined to locoregional area were treated with intraoperative electron beam boost to the celiac axis and peripancreatic nodal areas (15 Gy) and external irradiation (40 to 46 Gy in 4 to 5 weeks) including the gastric bed and upper abdominal nodal draining regions. At the time of evaluation for IORT, the disease was primary in 38 cases, recurrent but resectable in four (anastomosis), and unresectable in four (nodal). Post operative complications were reversible. Acute tolerance to the complete treatment program was acceptable. Late complications included life-threatening events: Six episodes of gastro intestinal bleeding (three of them had an arteriographic documentation of arterioenteric fistula) and nine with severe enteritis (five required reoperation). Other long-term treatment related complications were six cases of vertebral collapse. The median follow-up time for the entire group is 22 months. Locoregional recurrence/persistence of disease has been identified in five patients (three with residual and/or recurrent postsurgical tumor). Systemic tumor progression has been detected in 15 patients (11 in intra-abdominal sites). Overall actuarial survival for patients with positive or negative serosal involvement was 33% versus 56%. It is concluded that the treatment program described is able to induce a high locoregional tumor control rate (100%) when used strictly in an adjuvant setting and might control long term, a small portion of patients not amenable for curative surgery (2 out of 8 patients with confirmed residual post-surgical disease). Gastrointestinal bleeding and enteritis are findings that indicate treatment intensity at the upper limits of tissue tolerance. Assessment of long term tolerance of pancreatic parenchyma and large blood vessels (tissues included in the IRORT field) are pending for longer follow-up and the appropriate selective studies.