Analysis of in-field control and late toxicity for adults with early-stage Hodgkin's disease treated with chemotherapy followed by radiotherapy

Intensity modulated radiotherapy in early stage Hodgkin lymphoma patients: is it better than three dimensional conformal radiotherapy?

Background

Cure rate of early Hodgkin Lymphoma are high and avoidance of late toxicities is of paramount importance. This comparative study aims to assess the normal tissue sparing capability of intensity-modulated radiation therapy (IMRT) versus standard three-dimensional conformal radiotherapy (3D-CRT) in terms of dose-volume parameters and normal tissue complication probability (NTCP) for different organs at risk in supradiaphragmatic Hodgkin Lymphoma (HL) patients.

Methods

Ten HL patients were actually treated with 3D-CRT and all treatments were then re-planned with IMRT. Dose-volume parameters for thyroid, oesophagus, heart, coronary arteries, lung, spinal cord and breast were evaluated. Dose-volume histograms generated by TPS were analyzed to predict the NTCP for the considered organs at risk, according to different endpoints.

Results

Regarding dose-volume parameters no statistically significant differences were recorded for heart and origin of coronary arteries. We recorded statistically significant lower V30 with IMRT for oesophagus (6.42 vs 0.33, p = 0.02) and lungs (4.7 vs 0.1 p = 0.014 for the left lung and 2.59 vs 0.1 p = 0.017 for the right lung) and lower V20 for spinal cord (17.8 vs 7.2 p = 0.02). Moreover the maximum dose to the spinal cord was lower with IMRT (30.2 vs 19.9, p <0.001). Higher V10 with IMRT for thyroid (64.8 vs 95, p = 0.0019) and V5 for lungs (30.3 vs 44.8, p = 0.03, for right lung and 28.9 vs 48.1, p = 0.001 for left lung) were found, respectively. Higher V5 and V10 for breasts were found with IMRT (V5: 4.14 vs 20.6, p = 0.018 for left breast and 3.3 vs 17, p = 0.059 for right breast; V10: 2.5 vs 13.6 p = 0.035 for left breast and 1.7 vs 11, p = 0.07 for the right breast.) As for the NTCP, our data point out that IMRT is not always likely to significantly increase the NTCP to OARs.

Conclusions

In HL male patients IMRT seems feasible and accurate while for women HL patients IMRT should be used with caution.

Rationale for and preliminary results of proton beam therapy for mediastinal lymphoma

PURPOSE

To evaluate the potential of three-dimensional proton beam therapy (3D-PBT) for reducing doses to normal structures in patients with mediastinal lymphomas compared with conventional photon radiation therapy (RT).

METHODS AND MATERIALS

We treated 10 consecutive patients with mediastinal masses from lymphomas with 3D-PBT between July 2007 and February 2009 to 30.6-50.4 cobalt-Gray equivalents (CGE). Of those patients, 7 had primary refractory or recurrent disease, and 8 had Hodgkin lymphoma. Dosimetric endpoints were compared with those from conventional RT plans.

RESULTS

PBT delivered lower mean doses to the lung (6.2 vs. 9.5 Gy), esophagus (9.5 vs. 22.3 Gy), and heart (8.8 vs. 17.7 Gy) but not the breasts (5.9 vs. 6.1 Gy) than did conventional RT. Percentages of lung, esophagus, heart, and coronary artery (particularly the left anterior descending artery) volumes receiving radiation were consistently lower in the 3D-PBT plans over a wide range of radiation doses. Of the 7 patients who had residual disease on positron emission tomography before PBT, 6 (86%) showed a complete metabolic response.

CONCLUSIONS

In patients with mediastinal lymphomas, 3D-PBT produced significantly lower doses to the lung, esophagus, heart, and coronary arteries than did the current conventional RT. These lower doses would be expected to reduce the risk of late toxicities in these major organs.

Screening Hodgkin lymphoma survivors for radiotherapy induced cardiovascular disease

Long term prognosis of Hodgkin lymphoma (HL) survivors is affected by late toxicity of radiotherapy and chemotherapy. Cardiovascular complications of radiotherapy have been shown to have a great impact on the long term survival. The aim of this review is to summarize the available data on different screening modalities for cardiovascular disease and to suggest a screening program. Patients older than 45 years at HL diagnosis should be screened for coronary artery disease (CAD) starting 5 years after mediastinal radiotherapy; they are at increased risk of pre-existent atherosclerosis which can be accelerated by radiotherapy. Screening for CAD should start 10 years after radiotherapy in younger patients. The best screening modality for CAD is subject of discussion, based on the latest studies we suggest screening by Coronary artery calcium score measurements or CT-angiography. Valvular disorders should be looked for by echocardiography starting 10 years after radiotherapy. Electrocardiograms should be performed at each cardiovascular screening moment in order to detect arrhythmia's or conduction abnormalities. We suggest repeating these screening tests every 5 years or at onset of cardiovascular complaints; patients should be extensively instructed about signs and symptoms of cardiovascular disease. Furthermore traditional risk factors for cardiovascular disease should be carefully monitored and treated. We suggest determining a cardiovascular risk profile at diagnosis of HL in patients older than 45 years. In case of a high risk, treating HL without RT should be considered.

Reconstruction of 3D lung models from 2D planning data sets for Hodgkin's lymphoma patients using combined deformable image registration and navigator channels

PURPOSE

Late complications (cardiac toxicities, secondary lung, and breast cancer) remain a significant concern in the radiation treatment of Hodgkin's lymphoma (HL). To address this issue, predictive dose-risk models could potentially be used to estimate radiotherapy-related late toxicities. This study investigates the use of deformable image registration (DIR) and navigator channels (NCs) to reconstruct 3D lung models from 2D radiographic planning images, in order to retrospectively calculate the treatment dose exposure to HL patients treated with 2D planning, which are now experiencing late effects.

METHODS

Three-dimensional planning CT images of 52 current HL patients were acquired. 12 image sets were used to construct a male and a female population lung model. 23 "Reference" images were used to generate lung deformation adaptation templates, constructed by deforming the population model into each patient-specific lung geometry using a biomechanical-based DIR algorithm, MORFEUS. 17 "Test" patients were used to test the accuracy of the reconstruction technique by adapting existing templates using 2D digitally reconstructed radiographs. The adaptation process included three steps. First, a Reference patient was matched to a Test patient by thorax measurements. Second, four NCs (small regions of interest) were placed on the lung boundary to calculate 1D differences in lung edges. Third, the Reference lung model was adapted to the Test patient's lung using the 1D edge differences. The Reference-adapted Test model was then compared to the 3D lung contours of the actual Test patient by computing their percentage volume overlap (POL) and Dice coefficient.

RESULTS

The average percentage overlapping volumes and Dice coefficient expressed as a percentage between the adapted and actual Test models were found to be 89.2 +/- 3.9% (Right lung = 88.8%; Left lung = 89.6%) and 89.3 +/- 2.7% (Right = 88.5%; Left = 90.2%), respectively. Paired T-tests demonstrated that the volumetric reconstruction method made a statistically significant improvement to the population lung model shape (p < 0.05). The error in the results were also comparable to the volume overlap difference observed between inhale and exhale lung volumes during free-breathing respiratory motion (POL: p = 0.43; Dice: p = 0.20), which implies that the accuracies of the reconstruction method are within breathing constraints and would not be the confining factor in estimating normal tissue dose exposure.

CONCLUSIONS

The result findings show that the DIR-NC technique can achieve a high degree of reconstruction accuracy, and could be useful in approximating 3D dosimetric representations of historical 2D treatment. In turn, this could provide a better understanding of the biophysical relationship between dose-volume exposure and late term radiotherapy effects.

Concurrent epithelioid malignant peripheral nerve sheath tumor and papillary thyroid carcinoma in the treated field of Hodgkin's disease

BACKGROUND

Simultaneous malignancies in the field of radiation for Hodgkin's disease is an extremely rare event. A unique case of concurrent thyroid and neck mass in the postirradiation field of a young patient with Hodgkin's disease is presented.

METHODS AND RESULTS

Thyroidectomy and excision biopsy of the neck mass were performed. A 1.5-cm papillary thyroid carcinoma was identified in thyroidectomy and an initial diagnosis of undifferentiated malignant neoplasm was rendered on the neck mass biopsy. Subsequent surgical excision of the neck mass and immunohistochemical analysis revealed malignant peripheral nerve sheath tumor.

CONCLUSION

Concurrent malignancies in the field of treatment of Hodgkin's disease may occur. Rare malignancies including malignant peripheral nerve sheath tumor may be encountered along with the more common papillary thyroid carcinoma.

Monitoring for cardiovascular disease in survivors of childhood cancer: report from the Cardiovascular Disease Task Force of the Children's Oncology Group

Curative therapy for childhood cancer has improved significantly in the last 2 decades such that, at present, approximately 80% of all children with cancer are likely to survive > or = 5 years after diagnosis. Prevention, early diagnosis, and treatment of long-term sequelae of therapy have become increasingly more significant as survival rates continue to improve. Cardiovascular disease is a well-recognized cause of increased late morbidity and mortality among survivors of childhood cancer. The Children's Oncology Group Late Effects Committee and Nursing Discipline and Patient Advocacy Committee have recently developed guidelines for follow-up of long-term survivors of pediatric cancer. A multidisciplinary task force critically reviewed the existing literature to evaluate the evidence for the cardiovascular screening recommended by the Children's Oncology Group guidelines. In this review we outline the clinical manifestations of late cardiovascular toxicities, suggest modalities and frequency of monitoring, and address some of the controversial and unresolved issues regarding cardiovascular disease in childhood cancer survivors.

Radiotherapy of hodgkin lymphoma: indications, new fields, and techniques

In recent years, radiotherapy in patients with Hodgkin lymphoma has evolved considerably because of sophisticated imaging technologies and radiation delivery techniques. Even more recently, a new radiation field concept has emerged to ensure better normal tissue protection while preserving an excellent clinical outcome. The role of radiation therapy is also rapidly changing because the concept of a risk-adapted treatment strategy, in which combined-modality treatments were the order of the day, is now expanding into a concept of response-adapted treatments.

Dexrazoxane-associated risk for acute myeloid leukemia/myelodysplastic syndrome and other secondary malignancies in pediatric Hodgkin's disease

PURPOSE

Pediatric Oncology Group (POG) studies 9426 and 9425 evaluated dexrazoxane (DRZ) as a cardiopulmonary protectant during treatment for Hodgkin's disease (HD). We evaluated incidence and risk factors of acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) and second malignant neoplasms (SMNs).

PATIENTS AND METHODS

Treatment for low- and high-risk HD with doxorubicin, bleomycin, vincristine, and etoposide (ABVE) or dose-intensified ABVE with prednisone and cyclophosphamide (ABVE-PC), respectively, was followed by low-dose radiation. The number of chemotherapy cycles was determined by rapidity of the initial response. Patients were assigned randomly to receive DRZ (n = 239) or no DRZ (n = 239) concomitantly with chemotherapy to evaluate its potential to decrease adverse cardiopulmonary outcomes.

RESULTS

Ten patients developed SMN. Six of eight patients developed AML/MDS, and both solid tumors (osteosarcoma and papillary thyroid carcinoma) occurred in recipients of DRZ. Eight patients with SMN were first events. With median 58 months' follow-up, 4-year cumulative incidence rate (CIR) for AML/MDS was 2.55% +/- 1.0% with DRZ versus 0.85% +/- 0.6% in the non-DRZ group (P = .160). For any SMN, the CIR for DRZ was 3.43% +/- 1.2% versus CIR for non-DRZ of 0.85% +/- 0.6% (P = .060). Among patients receiving DRZ, the standardized incidence rate (SIR) for AML/MDS was 613.6 compared with 202.4 for those not receiving DRZ (P = .0990). The SIR for all SMN was 41.86 with DRZ versus 10.08 without DRZ (P = .0231).

CONCLUSION

DRZ is a topoisomerase II inhibitor with a mechanism distinct from etoposide and doxorubicin. Adding DRZ to ABVE and ABVE-PC may have increased the incidence of SMN and AML/MDS.

Comparison of three different mediastinal radiotherapy techniques in female patients: Impact on heart sparing and dose to the breasts

BACKGROUND AND PURPOSE

To study different radiotherapy techniques for female patients with mediastinal target volumes. Especially in highly curable diseases such as lymphoma, long-term survivors might develop late cardiac damage and radiation-induced second cancer.

PATIENTS AND METHODS

Planning CT scans were obtained in eight cases. We contoured the clinical target volume (three different scenarios with or without lower mediastinum and hili) and organs at risk and compared standard 6MV ap-pa opposed fields to a 3D conformal 4-field technique and a 7-field step-and-shoot IMRT technique and evaluated DVHs for each structure. The planning system was BrainSCAN 5.21 (BrainLAB, Heimstetten, Germany).

RESULTS

Target volume coverage did not improve significantly with 4-field or IMRT techniques. However, IMRT resulted in better dose reduction to the heart than the other techniques. The median heart dose (intermediately sized target volume) was 98% (95-100) with ap-pa fields, 56% (52-79) with the 4-field technique, and 39% (36-65) with IMRT, for example (p<0.05). Better heart sparing was achieved at all dose levels down to the 15% isodose. The median maximum dose to the breasts was lowest with IMRT. The breast volume receiving low doses (15% or less), however, was highest with IMRT. There was also a disadvantage in mean lung dose.

CONCLUSIONS

IMRT might result in a reduced cardiac complication risk. In younger females, however, this advantage might be offset by the risk of breast cancer. The best technique for a given patient depends on age, comorbidity, and the individual risk estimates for breast cancer and cardiac morbidity, respectively.

Involved-field radiotherapy for patients in partial remission after chemotherapy for advanced Hodgkin’s lymphoma

PURPOSE

The use of radiotherapy in patients with advanced Hodgkin's lymphoma (HL) is controversial. The purpose of this study was to describe the role of radiotherapy in patients with advanced HL who were in partial remission (PR) after chemotherapy.

METHODS

In a prospective randomized trial, patients <70 years old with previously untreated Stage III-IV HL were treated with six to eight cycles of mechlorethamine, vincristine, procarbazine, prednisone/doxorubicin, bleomycine, vinblastine hybrid chemotherapy. Patients in complete remission (CR) after chemotherapy were randomized between no further treatment and involved-field radiotherapy (IF-RT). Those in PR after six cycles received IF-RT (30 Gy to originally involved nodal areas and 18-24 Gy to extranodal sites with or without a boost).

RESULTS

Of 739 enrolled patients, 57% were in CR and 33% in PR after chemotherapy. The median follow-up was 7.8 years. Patients in PR had bulky mediastinal involvement significantly more often than did those in CR after chemotherapy. The 8-year event-free survival and overall survival rate for the 227 patients in PR who received IF-RT was 76% and 84%, respectively. These rates were not significantly different from those for CR patients who received IF-RT (73% and 78%) or for those in CR who did not receive IF-RT (77% and 85%). The incidence of second malignancies in patients in PR who were treated with IF-RT was similar to that in nonirradiated patients.

CONCLUSION

Patients in PR after six cycles of mechlorethamine, vincristine, procarbazine, prednisone/doxorubicine, bleomycine, vinblastine treated with IF-RT had 8-year event-free survival and overall survival rates similar to those of patients in CR, suggesting a definite role for RT in these patients.

Cardiac function after chemoradiation for esophageal cancer: comparison of heart dose-volume histogram parameters to multiple gated acquisition scan changes

In this paper we determine if preoperative chemoradiation for locally advanced esophageal cancer leads to changes in cardiac ejection fraction. This is a retrospective review of 20 patients treated at our institution for esophageal cancer between 2000 and 2002. Multiple gated acquisition cardiac scans were obtained before and after platinum-based chemoradiation (50.4 Gy). Dose-volume histograms for heart, left ventricle and left anterior descending artery were analyzed. Outcomes assessed included pre- and postchemoradiation ejection fraction ratio and percentage change in ejection fraction postchemoradiation. A statistically significant difference was found between median prechemoradiation ejection fraction (59%) and postchemoradiation ejection fraction (54%) (P = 0.01), but the magnitude of the difference was not clinically significant. Median percentage volume of heart receiving more than 20, 30 and 40 Gy were 61.5%, 58.5% and 53.5%, respectively. Our data showed a clinically insignificant decline in ejection fraction following chemoradiation for esophageal cancer. We did not observe statistically or clinically significant associations between radiation dose to heart, left ventricle or left anterior descending artery and postchemoradiation ejection fraction.

Patterns of Treatment Failure in Pediatric and Young Adult Patients With Hodgkin's Disease: Local Disease Control With Combined-Modality Therapy

Purpose

Refinement in managing pediatric Hodgkin's disease (HD) requires understanding of factors associated with local treatment failure. This study defines the cumulative incidence (CI) of local failure (LF) and prognostic factors for pediatric patients treated for HD with combined-modality therapy (CMT).

Patients and Methods

We enrolled 195 patients onto two prospective studies at St Jude Children's Research Hospital between 1990 and 2000. Patients received CMT with chemotherapy (vinblastine, doxorubicin, methotrexate, and prednisone [VAMP]; vinblastine, etoposide, prednisone, and doxorubicin; or VAMP/cyclophosphamide, vincristine, and procarbazine) and involved-field radiation therapy delivered to initial site(s) of disease on the basis of early response. Sites of disease involvement, treatment, and sites of failure were confirmed from the patients' medical record, imaging, and radiotherapy treatment records. We estimated the overall survival, event-free survival, and CI of LF.

Results

With a median follow-up of 7.6 years, the CI of LF was 10.9% and 11.6% at 5 and 10 years, respectively. Twenty-seven (14%) of 195 patients experienced recurrence of HD, and 22 (81%) of those experienced LF. Bulky mediastinal disease greater than one third transthoracic diameter predicted a higher incidence of LF, but did not predict failure in the mediastinum. Male sex, low initial hemoglobin, and bulky mediastinal disease were prognostic indicators of LF. Attenuation of radiation dose to 15 Gy based on response provides excellent infield control.

Conclusion

CMT provides excellent local disease control in children and young adults with HD. LF remains a primary site of disease recurrence, with male sex, low initial hemoglobin, and bulky mediastinal disease predicting for LF.

A Consensus Protocol: Image-improved Therapeutic Guidelines for Limited Adult Hodgkin's Disease

Hodgkin's disease (HD) has greatly benefited from new technologies in terms of less invasive and more accurate staging as well as improved overall and relapse-free survival. However, the likelihood of late adverse effects of treatment, including second tumors, has increased due to the longer survival of patients with HD. Today's trend is to aim at minimal therapeutic exposure while guaranteeing lower therapy-related morbidity. This encourages new research efforts but also leads to less uniformity in treatments, as observed in the Veneto Region in Italy. The Gruppo Veneto Linfomi, composed of representatives of Radiotherapy and Oncology Departments of the Veneto Region, has been analyzing this problem and proposing therapy guidelines since 1995. A set of 10 prognostic factors has been developed to identify three prognostic groups: highly favorable (HF) are patients up to 40 years of age presenting with stage I disease involving only one site of disease with a maximum tumor diameter (TD) of 5 cm and no adverse factors. In this group only mantle field irradiation is recommended if the disease is located in the neck or above, inverted-Y irradiation is recommended for distal subdiaphragmatic lesions, and subtotal nodal irradiation in all other cases. HF cases may also be treated like favorable cases with limited chemoradiation. Favorable (F) cases are patients in stage I with a TD greater than 5 cm and smaller than 10 cm or stage II, up to three sites of disease and negative prognostic factors for systemic disease. All other patients are included in the “not favorable” (NF) group at Ann Arbor stage I or II with any adverse prognostic factor. For the latter two groups, chemotherapy with the ABVD or Stanford V regimen precedes involved-field radiotherapy to sites with a TD of at least 5 cm. The total irradiation dose is determined by local disease extent and level of response to chemotherapy. Images on which the radiation fields are drawn serve as an important reference to improve the homogeneity of treatments. This protocol includes a list of adverse treatment effects (chemo- and/or radiotherapy) together with follow-up guidelines for the early detection of secondary cancers in previously irradiated patients.

Prospective study of combined modality treatment or radiotherapy alone in the management of early-stage adult Hodgkin's disease

PURPOSE

To determine the efficacy and toxicity of combined modality treatment (CMT) or radiotherapy (RT) alone in the management of clinical Stage I-IIA adult Hodgkin's disease patients.

METHODS AND MATERIALS

Forty-seven patients with supradiaphragmatic clinical Stage I-IIA Hodgkin's disease without bulky mediastinal lymphadenopathy were enrolled into this prospective study between September 1997 and February 2002. Patients with very favorable criteria presenting with one or two nonbulky nodal areas involved, an erythrocyte sedimentation rate of <50 mm/h, age <40 years, and either lymphocyte predominant or nodular sclerosing histologic findings were treated by RT alone. Patients missing any of these favorable criteria were classified as the other favorable group and were treated with three courses of doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapy followed by involved-field RT. The median age was 36 years (range, 19-53 years). Of the 47 patients, 15 were women and 32 were men. Only 3 patients were classified as the most favorable group and treated with mantle RT alone; the remaining 44 were treated with CMT.

RESULTS

The median follow-up was 51 months (range, 20-74 months). Only 2 patients developed recurrence, both out of the irradiated field, one in the contralateral neck and the other in the abdomen. The 5-year relapse-free and overall survival rate was 95.4% and 97.8%, respectively. Although none of the prognostic factors were statistically significant for relapse-free survival, a trend was noted for the response to chemotherapy (p = 0.06). Only 2 patients developed treatment-related complications. One patient treated with mantle RT alone developed severe ischemic heart disease and one in the CMT arm developed subclinical hypothyroidism.

CONCLUSION

Despite the short follow-up, CMT or RT alone tailored according to the clinical prognostic factors were successful in terms of disease control in clinical Stage I-IIA Hodgkin's disease. Longer follow-up is required to make definitive conclusions.

Combination chemotherapy plus low-dose involved-field radiotherapy for early clinical stage Hodgkin's lymphoma

PURPOSE

To present our long-term experience regarding the use of chemotherapy plus low-dose involved-field radiotherapy (IFRT) for clinical Stage I-IIA Hodgkin's lymphoma.

METHODS AND MATERIALS

We analyzed the data of 368 patients. Of these, 66 received mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) and 302 received doxorubicin (or epirubicin), bleomycin, vinblastine, and dacarbazine [A(E)BVD]. Patients with complete remission or very good partial remission were scheduled for low-dose IFRT (< or =3200 cGy).

RESULTS

The 10-year failure-free survival (FFS) and overall survival (OS) rate was 85% and 86%, respectively. A(E)BVD-treated patients had superior 10-year FFS and OS rates compared with MOPP-treated patients (87% vs. 75%, p = 0.009; and 93% vs. 71%, p = 0.0004, respectively). Only 10 of 41 relapses had any infield (irradiated) component. Of the complete responders/very good partial responders treated with low-dose IFRT, those who received <2800 cGy had inferior FFS but similar OS as those who received 2800-3200 cGy. Adverse prognostic factors for FFS included age > or =45 years, leukocytosis > or =10 x 10(9)/L, and extranodal extension. Secondary acute leukemia developed after MOPP with or without salvage therapy (n = 6) or after ABVD plus salvage therapy (n = 2). None of the nine secondary solid tumors developed within the RT fields.

CONCLUSION

IFRT at a dose of 2800-3000 cGy is highly effective in clinical Stage I-IIA HL patients who achieved a complete response or very good partial response with A(E)BVD. The long-term toxicity with respect to secondary malignancies appears to be acceptable.

Impact of chest wall and lung invasion on outcome of stage I–II Hodgkin's lymphoma after combined modality therapy

PURPOSE

To examine the impact of extranodal chest wall and lung invasion on the prognosis of patients with clinical Stage I-II Hodgkin's lymphoma treated with combined modality therapy.

MATERIALS AND METHODS

The outcome of 324 patients with clinical Stage I-II Hodgkin's lymphoma treated with combined modality therapy between 1981 and 1996 was analyzed. Twenty-two patients had chest wall invasion and 40 had invasion of lung parenchyma. The chemotherapy regimens used were ABVD in 182 patients (56%), MOPP/ABV(D) in 45 (14%), MOPP in 86 (27%), and other chemotherapy regimens in 11 patients (3%). This was followed by mantle/mediastinal radiotherapy (RT) in 163 patients (50%), extended-field RT in 135 patients (42%), and infradiaphragmatic RT in 26 patients (8%). The impact of chest wall and lung invasion on local relapse, disease-free survival, cause-specific survival, and overall survival was examined.

RESULTS

After a median follow-up of 8.3 years, the 5-year cause-specific and overall survival rate of the entire cohort was 93% and 90%, respectively. Compared with patients with no extranodal involvement, patients with chest wall invasion had significantly worse local control (89% vs. 68%, p = 0.005), disease-free survival (84% vs. 59%, p = 0.016), and cause-specific survival (94% vs. 86%, p = 0.009). Overall survival was also worse among patients with chest wall invasion, but not significantly so (90% vs. 82%, p = 0.10). Among the 16 patients with chest wall invasion but without lung invasion, 7 progressed during treatment or relapsed, 6 with local failure (crude relapse rate 44%, 95% confidence interval [CI] 19-68%), and 5 died (crude death rate 31%, 95% CI 9-54%). After adjusting for other significant prognostic factors, patients with chest wall invasion had significantly worse local control (hazard ratio 2.8, 95% CI 1.2-6.3), disease-free survival (hazard ratio 2.3, 95% CI 1.1-4.8), and cause-specific survival (hazard ratio 2.8, 95% CI 1.1-6.8). Lung invasion was not significantly associated with any of the outcomes assessed.

CONCLUSIONS

Chest wall invasion is an adverse prognostic factor among clinical Stage I-II Hodgkin's lymphoma patients treated with combined modality therapy, although we did not find a worse outcome for patients with lung invasion. Efforts to reduce treatment intensity in these patients should be undertaken with caution, recognizing their increased risk of local relapse.

Clinical implications of radiation-induced genomic instability

Radiation-induced genomic instability encompasses a range of measurable end points such as chromosome destabilization, sister chromatid exchanges, gene mutation and amplification, late cell death and aneuploidy, all of which may be causative factors in the development of clinical disease, including carcinoma. Clinical implications of genomic instability can be broadly grouped into two main areas: as a marker for increased cancer risk/early detection, and as a consequence of radiation therapy (IR) that may be causative of, or a strong marker for, the induction of a therapy-induced second malignancy. Research in human populations has been limited, but broadly encompasses three populations: those exposed to alpha-particle irradiation, those with a cancer diagnosis who were examined for lymphocyte sensitivity to IR as a biomarker for risk of cancer induction, and those who successfully completed radiation therapy for an index cancer and who were examined for the induction of a second malignancy. This review examines each of those populations in turn and offers some potential future research directions to better elucidate the role of radiation-induced genomic instability in clinical disease.

PET in lymphoma: what are the oncologist's needs?

Fluorine-18 fluorodeoxyglucose positron emission tomography (PET) has a number of potential advantages for the oncologist in refining and improving the management of lymphomas. Currently the most promising appear to be in the early prediction of response to chemotherapy, evaluation of the residual mass and improved radiotherapy planning. Other important areas which require assessment are its value in refining prognostic indices at staging and its role in follow-up. The added value of the new combined PET-CT scanners requires careful evaluation in each of these settings, where combined morphological and functional information may provide optimal disease assessment. The ultimate aim is to improve the management of patients with lymphoma by identifying those patients who can be cured with minimal treatment and equally those for whom conventional treatment is doomed to failure and in whom more intensive strategies should be employed from the outset.