G. Frezza

THE IMPACT OF CONTOURING UNCERTAINTY ON RECTAL 3D DOSE- VOLUME DATA: RESULTS OF A DUMMY RUN IN A MULTICENTER TRIAL (AIROPROS01- 02)

PURPOSE To estimate the impact of the uncertainty in contouring the rectum on rectal dose-volume parameters and normal tissue complication probability (NTCP) in a prospective (AIROPROS01-02) investigation about rectal toxicity. METHODS AND MATERIALS The participants in a prospective trial (18 observers) were asked to draw the external contour of the rectum of 4 sample patients (3 patients undergoing radical conformal radiotherapy, 1 patient undergoing post-prostatectomy) on CT images (0.5 cm spacing) using a 3D treatment planning system. A previously accepted definition of cranial and caudal borders of the rectum was applied. For each patient, four- and six-field 3D-conformal techniques (70-76 Gy, ICRU dose) were planned and DVH/dose statistics of the rectum were calculated. The impact of interobserver variability on rectal volume, cranial and caudal borders, mean, maximum, and median rectal dose, percentage of rectum receiving more than 40, 45, 50, 55, 60, 65, 70, and 75 Gy (V(40)-V(75)), and NTCP were investigated. RESULTS Concerning DVHs, 9/18 observers tended to have some systematic deviation. However, deviations from the mean values greater than 5% were found only in 1/9 because of a systematic discrepancy in the caudal limit assessment (mean deviation from the most frequently chosen slice: 8 mm). No other observers showed a mean deviation in the cranial or the caudal limit definition greater than 5.8 mm. For another observer, it was possible to clearly assess the cause of a relatively large systematic deviation for DVH parameters. In both cases, the observers were contacted to avoid these systematic deviations. When considering the remaining 16/18 observers, the average values of SD for V(40)-V(75) ranged between 1% and 4% and were found to be lower (<3%) for the 3 nonoperated patients. The average values of the SD were around 1.5-2 Gy and less than 1.5% for mean/median dose and NTCPs, respectively. CONCLUSIONS Concerning the uncertainty in rectum definition, the collection of rectal dose-volume data in multicenter investigations seems to be feasible after a clear and previously accepted definition of rectum is assessed. However, even with a general agreement on rectum definition, contouring appears to be a quite significant source of uncertainty. A dummy run procedure is useful in identifying possible discrepancies among single observers and in assessing reliable confidence levels on dose-volume constraints because of contouring uncertainty, making the dummy run mandatory in multicenter trials evaluating 3D dose-volume data.

Isolated Central Nervous System Relapse in Aggressive Non-Hodgkin's Lymphoma: the Bologna Experience

Isolated central nervous system (CNS) relapse was evaluated in terms of incidence, risk factors, and outcome in a consecutive cohort of 175 patients with aggressive non-Hodgkins lymphoma in which no case of lymphoblastic or Burkitts lymphoma was encountered. All these patients had obtained a complete remission with first-line treatment and none had received prophylactic CNS treatment at diagnosis. Nine patients (5.2%) developed isolated CNS relapse after a median of 8 months from diagnosis. CNS involvement was documented by cerebrospinal fluid (CSF) cytology in 4 patients and on the basis of radiologic and clinical features in 5 others. Factors significantly associated with a greater likelihood of CNS relapse were advanced stage, B symptoms, bone marrow involvement, and high LDH levels in univariate analysis with only advanced stage being of significance in multivariate analysis. All relapsed CNS lymphoma patients died within a median time of 4 months from the disease recurrence, confirming the poor prognosis after CNS relapse and stressing the need to develop new treatment strategies for patients at high risk of CNS recurrence.

Combined therapy of localized Ewing's sarcoma of bone: Analysis of results in 100 patients

From 1979 to 1986, 182 patients with biopsy proven diagnosis of Ewings sarcoma of bone were observed. One hundred of the 182 patients (72 males, 28 females, median age 15.8 years) with localized disease and no previous treatment were treated with chemotherapy (VCR, ADM, CTX, D-ACT) for 15-18 months. Local treatment was radiotherapy (42 patients), surgery (31 patients), or a combination of both (27 pts). Radiation doses ranged from 45 to 64 Gy given with conventional fractionation. Median follow-up was 51.2 months (24-106). Overall and disease-free survival were, respectively, 58.7 and 42.6%. Resected patients tended to have a better local control (Surgery 93.6%, Surgery + Radiation therapy 92.6%, Radiation therapy 69.1%). Disease-free survival was significantly related to the volume of the primary tumor (bulky: 33.2%, not-bulky: 57.7%), to site (extremities 54.6%, central sites 16.6%, other sites 40.9%), and to local treatment (Radiation therapy 30.3%, Surgery + Radiation therapy 47.9%, Surgery 59.1%). These results are, however, biased because resected patients tended to have smaller tumors in favorable sites.

Pattern of p63 expression in squamous cell carcinoma of the oral cavity.

P63 is a recently discovered gene harbouring different isoforms by alternate splicing. The two main isoforms, TAp63 and ΔNp63, have opposite functions, being responsible for cell-cycle arrest and cell proliferation, respectively. In addition, new isoforms have been described with the same sequence as TAp63 and ΔNp63, but lacking exon 4 (Δ4Tap63 and ΔNp73L). P63 as detected using immunohistochemistry is present in squamous cell carcinomas. To better define the role of p63 in squamous cell carcinomas of the oral cavity (OSCC), 39 patients were investigated using immunohistochemical analysis with a monoclonal antibody recognising all p63 isoforms and an anti-Ki67 antibody. Reverse-transcription polymerase chain reaction (PCR) and nested PCR were also performed using isoform-specific primers to evaluate the p63 mRNA expression pattern. Using immunohistochemistry, p63 was always present in OSCC, and its distribution was similar to that of Ki67. The percentage of positive cells increased from normal to neoplastic mucosa, but there was no relationship between the number of p63 positive cells and prognosis. P63 mRNA was found in all patients. The truncated isoforms Δ4TAp63 and ΔNp73L were more frequently expressed in patients presenting with metastases. ΔNp73L was found in 66.6% of tumours with lymph-node metastases, but in only 33.3% of those devoid of lymph-node metastases at presentation. An impaired expression of the p63 isoforms might favour cell proliferation and indirectly enhance the metastasising capacity of OSCC.

Stereotactic Ablative Radiotherapy for stage I histologically proven non-small cell lung cancer: An Italian multicenter observational study

OBJECTIVES Aim of this retrospective multicenter observational study was to provide data on outcomes and prognostic factors in patients affected with stage I histologically confirmed NSCLC treated with Stereotactic Ablative Radiotherapy (SABR, or Stereotactic Body Radiotherapy, SBRT) outside clinical trials. MATERIALS AND METHODS We analyzed a cohort of 196 patients with histological/cytological diagnosis of NSCLC. Median age at treatment was 75 years old; median tumor diameter was 2.48 cm, and median GTV 13.3 cc. One hundred fifty-five patients had stage IA disease (79.1%) and 41 patients stage IB disease (20.9%). Total doses ranged from 48 to 60 Gy in 3-8 fractions. Primary endpoints of the study were safety (acute and late toxicity) and efficacy (Local Control, Disease-Free Survival, Overall and Cancer-Specific Survival). RESULTS Median follow-up time was 30 months. The percentage of grade ≥2 pulmonary toxicity was 3%, and the 30 and 60 days mortality rate was 0%. Local Recurrence-Free Survival was 89.7% at 3 years. Fifty-nine patients (30.1%) had at least one failure (local and/or nodal and/or distant), with a Disease-Free Survival (DFS) rate at 3 years of 65.5%. Overall Survival (OS) and Cancer-Specific Survival (CSS) rates were 68% and 82.1% at 3 years, respectively. Median time to any recurrence was 15 months, while median overall survival time was 54 months. At multivariate analysis, stage IB was the only variable associated to a decrease in DFS, OS and CSS (HR 2.77, p = 0.006; HR 2.38, p = 0.009; HR 4.06, p ≤ 0.001, respectively). A difference in survival according to stage was also evident at the log-rank test (p ≤ 0.0001 for CSS and OS). CONCLUSION The results of the present study support the routine use of SABR for stage I NSCLC in a daily practice environment. The only prognostic factor that has been confirmed by our analysis was tumor stage (IA vs. IB).

Nongastrointestinal mucosa-associated lymphoid tissue (MALT) lymphomas: Clinical and therapeutic features of 24 localized patients

BACKGROUND Peripheral B-cell lymphoma of the marginal zone (MALT, low-grade), presenting as localized, extranodal disease, usually affects the elderly. The gastrointestinal tract is the most frequently involved extranodal location, representing 70% of all MALT lymphomas. Recently, numerous other extranodal sites involved by MALT lymphomas have also been described. PATIENTS AND METHODS From January 1990 to October 1995, 24 patients with untreated nongastrointestinal low-grade MALT lymphoma were submitted to treatments ranging from the local approach of radiotherapy and local alpha-interferon (alpha-IFN) administration to chemotherapy. The tumours were located in the lung (seven cases), conjunctiva (four cases), lachrymal gland and orbital soft tissue (four cases), salivary glands (three cases), skin (three cases), breast (two cases), and thyroid (one case). All patients had low-grade stage IE tumours. RESULTS Chemotherapy was administered in 11 patients (six with lung, three with salivary gland, one with breast, and one with thyroid locations); radiation therapy was employed in seven patients (three with lachrymal gland, three with skin, and one with breast locations); local alpha-IFN administration was administered in five patients (four with conjunctival, and one with lachrymal gland sites); and surgery was employed in one patient with a lung tumour. All patients achieved complete remissions; three local recurrences and two relapses in other sites were observed. The global five-year survival rate was 100% with a relapse-free survival rate of 79%. CONCLUSIONS These data confirm the significant efficacy of different therapeutic approaches to specific sites inbes obtaining a good remission rate for nongastrointestinal localized low-grade MALT lymphomas.

Adult Lymphoblastic Lymphoma: Clinical Features and Prognostic Factors in 53 Patients

Lymphoblastic lymphoma (LBL) in adult patients is recognized as a particular entity in the high-grade non-Hodgkins lymphoma (HG-NHL) group with characteristic clinical and prognostic features. Initially, polychemotherapy normally used in HG-NHL failed to produce long-term relapse-free survival because of progression disease in the CNS and in the bone marrow. Subsequently, the intensification of therapy using multimodality aggressive acute lymphoblastic leukemia (ALL) treatments led to an increase in long-term relapse-free survival. We analyzed retrospectively 53 adult patients with LBL according to the Kiel classification and the criteria by Nathwani et al. Therapeutic modifications depended upon the different times of diagnosis. Twenty-one patients received the modified L17 regimen, 13 patients were treated with the L0288 regimen, and 19 patients were submitted to the L20 protocol. There was no significant differences in CR rates among the three protocols: 48% vs 54% vs 63%, respectively. Nineteen of 29 patients who achieved CR were alive and relapse-free at a median follow-up of 84 months. Ten of the CR patients underwent autologous bone marrow transplantation (ABMT) to consolidate the first response and 7 of them are alive and relapse-free. Early stage of disease, age < 30 years, low LDH levels, the absence of leukemic phase at diagnosis, and, in particular the attainment of CR were all features of patients with good prognosis. Our study confirms the role of intensive polychemotherapeutic regimens including CNS prophylaxis, the significance of a score model of prognostic factors, and of the role of ABMT (or allogeneic bone marrow transplantation) in the treatment of adult LBL.

Patterns of failure in nasopharyngeal cancer treated with megavoltage irradiation

From 1976 to 1982, 78 patients with nasopharyngeal cancer (NPC) were treated with definitive megavoltage irradiation in accordance with a uniform protocol. The results of treatment were analyzed and prognostic factors reviewed. The incidence of primary failures was directly related to the extent of nasopharyngeal disease, since the relapse rate was 11% in T1T2 patients compared with 37.5% in T3T4 patients. Similarly, failure in the neck correlated with the N stage, being negligible for N0 and N1, while 35.7% for N3. The presence of bulky cervical nodes was associated with a higher risk for metastases: hematogenous dissemination occurred in 50% of N3B patients. The histology pattern seemed to significantly affect the ultimate outcome of patients with NPC, since disease-free survival was 65.5% in patients with a diagnosis of undifferentiated carcinoma (UC) and 23.8% in patients with squamous cell carcinoma (SC). The major cause of poor survival in this latter patient group was not only a higher recurrence rate of both primary and nodal disease but a greater incidence of distant metastases as well.

Monitoring Bulky Mediastinal Disease with Gallium-67, CT-Scan and Magnetic Resonance Imaging in Hodgkin's Disease and High-Grade Non-Hodgkin's Lymphoma

Treatment of both Hodgkins disease (HD) and high-grade non-Hodgkins lymphoma (HG-NHL) with bulky presentation at diagnosis frequently results in residual masses detected radiologically. Conventional diagnostic radiology and computed tomography (CT) are generally unable to detect the differences between tumor tissue and fibrosis. Gallium-67-citrate (67Ga) SPECT and magnetic resonance imaging (MRI) can potentially differentiate residual active tumor tissue and fibrosis. Thirty-three patients with HD or HG-NHL presenting with bulky mediastinal disease were studied with CT, 67Ga SPECT, and MRI (only for 16 patients) at diagnosis, after two-thirds of their chemotherapy, at the end of chemotherapy, and after radiotherapy in order to evaluate the mediastinal region on the basis of persistence of residual masses and activity of pathological tissue. After treatment, all patients with 67Ga-negative (30/33) disease are still in continuous complete response. Among the three 67Ga-positive patients, 2 relapsed within one year and another one is still alive without evidence of disease. Regarding MRI, two patients were found to be positive, one of them concomitant with 67Ga-positivity; both patients survive in complete response. In lymphoma patients with bulky mediastinal presentation, the 67Ga SPECT remains the preferable imaging technique for monitoring and differentiating the eventual active residual tumor. In combination, CT and 67Ga SPECT represent a suitable complete imaging approach to the radiological diagnosis which may be useful in these particular patients. MRI could probably be considered as a second-line method and from our data would be used only in selected cases because of the high cost, accessibility, and lower specificity as opposed to 67Ga SPECT in evaluating potentially active residual disease.

Serum LDH Concentration in Non-Hodgkin’s Lymphomas

Serum lactate dehydrogenase (LDH) activity is increased in many tumor-bearing patients and can be used as a prognostic marker. We studied serum LDH concentration in 94 consecutive patients with non-Hodgkins lymphoma who were histologically classified according to the Kiel Classification and were grouped according to the Non-Hodgkins Lymphoma Pathologic Classification Project Working Formulation. 74 patients were studied at diagnosis, and 20 of them (27%) had an LDH level higher than 250 U/l. High LDH levels were more frequent in cases of true histiocytic, high-grade, and intermediate-grade malignancy lymphoma (4 of 7, 7 of 14, and 7 of 20, respectively) than in cases of low-grade lymphoma (2 of 33). A close relationship of LDH to several prognosis-related disease features was found, including general symptoms, bulky disease, big mediastinal tumor, huge hepatosplenomegaly, bone marrow involvement, and a leukemic syndrome. LDH was higher than normal in a high proportion of cases who were studied in relapse (13 of 20, 65%). These data suggest that in non-Hodgkins lymphomas the LDH serum concentration is not independent of other disease features, so that the prognostic value of LDH is probably lower than expected from previous studies. Serum LDH activity decreased to normal in all cases of complete remission, but also in cases of partial remission, suggesting that measuring enzyme activity is of a limited usefulness for detecting and monitoring minimal residual disease. For that purpose, LDH isoenzyme studies would be more appropriate.