The value of post-operative chemotherapy after chemoradiotherapy in patients with high-risk locally advanced rectal cancer-results from the RAPIDO trial.

BACKGROUND: Pre-operative chemoradiotherapy (CRT) rather than radiotherapy (RT) has resulted in fewer locoregional recurrences (LRRs), but no decrease in distant metastasis (DM) rate for patients with locally advanced rectal cancer (LARC). In many countries, patients receive post-operative chemotherapy (pCT) to improve oncological outcomes. We investigated the value of pCT after pre-operative CRT in the RAPIDO trial. PATIENTS AND METHODS: Patients were randomised between experimental (short-course RT, chemotherapy and surgery) and standard-of-care treatment (CRT, surgery and pCT depending on hospital policy). In this substudy, we compared curatively resected patients from the standard-of-care group who received pCT (pCT+ group) with those who did not (pCT- group). Subsequently, patients from the pCT+ group who received at least 75% of the prescribed chemotherapy cycles (pCT ≥75% group) were compared with patients who did not receive pCT (pCT-/- group). By propensity score stratification (PSS), we adjusted for the following unbalanced confounders: age, clinical extramural vascular invasion, distance to the anal verge, ypT stage, ypN stage, residual tumour, serious adverse event (SAE) and/or readmission within 6 weeks after surgery and SAE related to pre-operative CRT. Cumulative probability of disease-free survival (DFS), DM, LRR and overall survival (OS) was analysed by Cox regression. RESULTS: In total, 396/452 patients had a curative resection. The number of patients in the pCT+, pCT >75%, pCT- and pCT-/- groups was 184, 112, 154 and 149, respectively. The PSS-adjusted analyses for all endpoints demonstrated hazard ratios between approximately 0.7 and 0.8 (pCT+ versus pCT-), and 0.5 and 0.8 (pCT ≥75% versus pCT-/-). However, all 95% confidence intervals included 1. CONCLUSIONS: These data suggest a benefit of pCT after pre-operative CRT for patients with high-risk LARC, with approximately 20%-25% improvement in DFS and OS and 20%-25% risk reductions in DM and LRR. Compliance with pCT additionally reduces or improves all endpoints by 10%-20%. However, differences are not statistically significant.

Continuation of fluoropyrimidine treatment with S-1 after cardiotoxicity on capecitabine- or 5-fluorouracil-based therapy in patients with solid tumours: a multicentre retrospective observational cohort study.

BACKGROUND: Capecitabine- or 5-fluorouracil (5-FU)-based chemotherapy is widely used in many solid tumours, but is associated with cardiotoxicity. S-1 is a fluoropyrimidine with low rates of cardiotoxicity, but evidence regarding the safety of switching to S-1 after 5-FU- or capecitabine-associated cardiotoxicity is scarce. PATIENTS AND METHODS: This retrospective study (NCT04260269) was conducted at 13 centres in 6 countries. The primary endpoint was recurrence of cardiotoxicity after switch to S-1-based treatment due to 5-FU- or capecitabine-related cardiotoxicity: clinically meaningful if the upper boundary of the 95% confidence interval (CI; by competing risk) is not including 15%. Secondary endpoints included cardiac risk factors, diagnostic work-up, treatments, outcomes, and timelines of cardiotoxicity. RESULTS: Per protocol, 200 patients, treated between 2011 and 2020 [median age 66 years (range 19-86); 118 (59%) males], were included. Treatment intent was curative in 145 (73%). Initial cardiotoxicity was due to capecitabine (n = 170), continuous infusion 5-FU (n = 22), or bolus 5-FU (n = 8), which was administered in combination with other chemotherapy, targeted agents, or radiotherapy in 133 patients. Previous cardiovascular comorbidities were present in 99 (50%) patients. Cardiotoxic events (n = 228/200) included chest pain (n = 125), coronary syndrome/infarction (n = 69), arrhythmia (n = 22), heart failure/cardiomyopathy (n = 7), cardiac arrest (n = 4), and malignant hypertension (n = 1). Cardiotoxicity was severe or life-threatening in 112 (56%) patients and led to permanent capecitabine/5-FU discontinuation in 192 (96%). After switch to S-1, recurrent cardiotoxicity was observed in eight (4%) patients (95% CI 2.02-7.89, primary endpoint met). Events were limited to grade 1-2 and occurred at a median of 16 days (interquartile range 7-67) from therapy switch. Baseline ischemic heart disease was a risk factor for recurrent cardiotoxicity (odds ratio 6.18, 95% CI 1.36-28.11). CONCLUSION: Switching to S-1-based therapy is safe and feasible after development of cardiotoxicity on 5-FU- or capecitabine-based therapy and allows patients to continue their pivotal fluoropyrimidine-based treatment.

Quality of life and cost effectiveness in a randomized trial of patients with colorectal cancer and peritoneal metastases.

BACKGROUND: The aim was to compare health-related quality-of-life (HRQOL) and cost-effectiveness between cytoreductive surgery with intraperitoneal chemotherapy (CRS + IPC) and systemic chemotherapy for patients with colorectal peritoneal metastases. METHODS: Patients included in the Swedish Peritoneal Trial comparing CRS + IPC and systemic chemotherapy completed the EORTC QLQ-C30 and SF-36 questionnaires at baseline, 2, 4, 6, 12, 18, and 24 months. HRQOL at 24 months was the primary endpoint. EORTC sum score, SF-36 physical and mental component scores at 24 months were calculated and compared for each arm and then referenced against general population values. Two quality-adjusted life-year (QALY) indices were applied (EORTC-8D and SF-6D) and an incremental cost-effectiveness ratio (ICER) per QALY gained was calculated. A projected life-time ICER per QALY gained was calculated using predicted survival according to Swedish population statistics. RESULTS: No statistical differences in HRQOL between the arms were noted at 24 months. Descriptively, survivors in the surgery arm had higher summary scores than the general population at 24 months, whereas survivors in the chemotherapy arm had lower scores. The projected life-time QALY benefit was 3.8 QALYs in favor of the surgery arm (p=0.06) with an ICER per QALY gained at 310,000 SEK (EORTC-8D) or 362,000 SEK (SF-6D) corresponding to 26,700-31,200 GBP. CONCLUSION: The HRQOL in patients with colorectal peritoneal metastases undergoing CRS + IPC appear similar to those receiving systemic chemotherapy. Two-year survivors in the CRS + IPC arm have comparable HRQOL to a general population reference. The treatment is cost-effective according to NICE guidelines.

Cytoreductive surgery and intraperitoneal chemotherapy versus systemic chemotherapy for colorectal peritoneal metastases: A randomised trial.

BACKGROUND: First-line treatment of isolated resectable colorectal peritoneal metastases remains unclear. This study (the Swedish peritoneal study) compares cytoreductive surgery and intraperitoneal chemotherapy (surgery arm) with systemic chemotherapy (chemotherapy arm). METHODS: Patients deemed resectable preoperatively were randomised to surgery and intraperitoneal 5-fluorouracil 550 mg/m(2)/d for 6 d with repeated courses every month or to systemic oxaliplatin and 5-fluorouracil regimen every second week. Both treatments continued for 6 months. Primary end-point was overall survival (OS) and secondary end-points were progression-free survival (PFS), and morbidity. RESULTS: The study terminated prematurely when 48 eligible patients (24/arm) were included due to recruitment difficulties. Two-year OS was 54% in the surgery arm and 38% in the chemotherapy arm (p = 0.04). After 5 years, 8 versus 1 patient were alive, respectively (p = 0.02). Median OS was 25 months versus 18 months, respectively, hazard ratio 0.51 (95% confidence interval: 0.27-0.96, p = 0.04). PFS in the surgery arm was 12 months versus 11 months in the chemotherapy arm (p = 0.16) with 17% versus 0% 5-year PFS. Grade III-IV morbidity was seen in 42% and 50% of the patients, respectively. No mortalities. CONCLUSIONS: Cytoreductive surgery with intraperitoneal chemotherapy may be superior to systemic oxaliplatin-based treatment of colorectal cancer with resectable isolated peritoneal metastases.(ClinicalTrials.gov nr:NCT01524094).

A randomized study of KRAS-guided maintenance therapy with bevacizumab, erlotinib or metronomic capecitabine after first-line induction treatment of metastatic colorectal cancer: the Nordic ACT2 trial.

BACKGROUND: Maintenance treatment (mt) with bevacizumab (bev) ± erlotinib (erlo) has modest effect after induction chemotherapy in metastatic colorectal cancer (mCRC). We hypothesized the efficacy of erlo to be dependent on KRAS mutational status and investigated this by exploring mt strategies with bev ± erlo and low-dose capecitabine (cap). PATIENTS AND METHODS: Included patients had mCRC scheduled for first-line therapy, Eastern Cooperative Oncology Group (ECOG) 0-1 and no major comorbidities. Treatment with XELOX/FOLFOX or XELIRI/FOLFIRI + bev was given for 18 weeks. After induction, patients without progression were eligible for randomization to mt; KRAS wild-type (wt) patients were randomized to bev ± erlo (arms wt-BE, N = 36 versus wt-B, N = 35), KRAS mutated (mut) patients were randomized to bev or metronomic cap (arms mut-B, N = 34 versus mut-C, N = 33). Primary end point was progression-free survival (PFS) rate (PFSr) at 3 months after start of mt. A pooled analysis of KRAS wt patients from the previous ACT study was performed. RESULTS: We included 233 patients. Median age was 64 years, 62% male, 68% ECOG 0, 52% with primary tumor in situ. A total of 138 patients started mt after randomization. PFSr was 64.7% versus 63.6% in wt-B versus wt-BE, P = 1.000; and 75% versus 66.7% in mut-B versus mut-C, P = 0.579, with no significant difference in median PFS and overall survival (OS). In the pooled cohort, median PFS was 3.7 months in wt-B (N = 64) and 5.7 months in wt-BE (N = 62) (hazard ratios 1.03, 95% confidence interval 0.70-1.50, P = 0.867). The frequency of any grade 3/4 toxicities during mt was: 28%/58%/18%/15% (wt-B/wt-BE/mut-B/mut-C). CONCLUSIONS: Addition of erlo to bev as mt in KRAS wt mCRC did not significantly improve PFS or OS, but it did increase toxicity. KRAS status does not seem to influence the outcome of treatment with erlotinib. Metronomic cap warrants further investigation in mt strategies, given our explorative results. CLINICALTRIALSGOV: NCT01229813.

A randomized phase III trial on maintenance treatment with bevacizumab alone or in combination with erlotinib after chemotherapy and bevacizumab in metastatic colorectal cancer: the Nordic ACT Trial.

BACKGROUND: The main objective was to study the effect on progression-free survival (PFS) of adding erlotinib to bevacizumab as maintenance treatment following chemotherapy and bevacizumab as first-line treatment of metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Patients with untreated mCRC received doublet chemotherapy + bevacizumab during 18 weeks and those without tumor progression were eligible for randomization to bevacizumab + erlotinib (arm A) or bevacizumab alone (arm B), until progression or unacceptable toxic effect. RESULTS: Of the 249 patients enrolled, 80 started maintenance treatment in arm A and 79 in arm B. The rate of any grade 3/4 toxic effect was 53% in arm A and 13% in arm B. Median PFS was 5.7 months in arm A and 4.2 months in arm B (HR = 0.79; 95% confidence interval 0.55-1.12; P = 0.19). Overall survival (OS) from start of induction chemotherapy was 26.7 months in the randomized population, with no difference between the two arms. CONCLUSIONS: The addition of erlotinib to bevacizumab as maintenance treatment after first-line chemotherapy in mCRC did not improve PFS significantly. On-going clinical and translational studies focus on identifying subgroups of patients that may benefit from erlotinib in the maintenance setting. CLINICAL TRIALS NUMBER: NCT00598156.

A window of opportunity phase II study of enzastaurin in chemonaive patients with asymptomatic metastatic colorectal cancer.

BACKGROUND: Preclinically, protein kinase C and AKT activation can be inhibited by enzastaurin and reduce tumor growth of colorectal cancer cells. In asymptomatic patients with metastatic colorectal cancer (mCRC), enzastaurin activity was evaluated by measuring the 6-month progression-free survival (PFS) rate in a window study design. PATIENTS AND METHODS: Chemonaive patients with asymptomatic mCRC who did not require immediate chemotherapy-induced tumor reduction received a 400-mg thrice daily loading dose of enzastaurin on day 1 of cycle 1, followed by 500 mg once daily for the remaining 28-day cycles. Progression was assessed on the basis of radiographic imaging, rise in carcinoembryonic antigen or lactate dehydrogenase (LDH) levels or by appearance of clinical symptoms. RESULTS: Twenty-eight patients received daily enzastaurin. The 6-month PFS rate was 28% [95% confidence interval (CI) 13%-45%] and median PFS was 1.9 months (95% CI 1.8-4.5 months). Twelve (43%) patients had stable disease with a median duration of 6.1 months. The survival rate at 20 months was 77% (95% CI 47%-92%). No grade 4 toxicity was reported and grade 3 toxic effects were observed in three patients with one patient showing probable drug-related elevation of liver transaminases. CONCLUSION: The window design in asymptomatic patients with mCRC can be safely applied to assess the activity and safety of novel cytostatic agents like enzastaurin.

Early prediction of response to first-line chemotherapy by sequential [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography in patients with advanced colorectal cancer.

BACKGROUND: To evaluate [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), for early evaluation of response to palliative chemotherapy and for prediction of long-term outcome, in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: In a randomized trial, patients with mCRC received irinotecan-based combination chemotherapy. FDG-PET was carried out before treatment and after two cycles in 51 patients at two centers. Visual changes in tumor FDG uptake and changes measured semi-automatically, as standard uptake values (SUVs), were compared with radiological response after four and eight cycles. RESULTS: The mean baseline SUV for all tumor lesions per patient was higher in nonresponders than in responders (mean 7.4 versus 5.6, P = 0.02). There was a strong correlation between metabolic response (changes in SUV) and objective response (r = 0.57, P = 0.00001), with a sensitivity of 77% and a specificity of 76%. There was no significant correlation between metabolic response and time to progression (P = 0.5) or overall survival (P = 0.1). CONCLUSIONS: Although metabolic response assessed by FDG-PET reflects radiological tumor volume changes, the sensitivity and specificity are too low to support the routine use of PET in mCRC. Furthermore, PET failed to reflect long-term outcome and can, thus, not be used as surrogate end point for hard endpoint benefit.

Phase I study of UFT plus leucovorin with radiotherapy in patients with inextirpable non-rectal gastrointestinal cancer.

BACKGROUND AND PURPOSE: Chemoradiotherapy is increasingly used in the primary management of patients with loco-regionally advanced gastrointestinal (GI) cancer. Oral chemotherapy with uracil and tegafur (UFT) plus leucovorin (LV) may represent a convenient way of delivering protracted infusion of fluorouracil. Our goal was to evaluate the safety of UFT plus LV combined with radiation and determine the maximum-tolerated dose (MTD) and a recommended dose for further testing. PATIENTS AND METHODS: Patients with inextirpable GI cancer received escalating doses of UFT (starting at 300 mg/m(2)/d with 50 mg/m(2)/d increments between consecutive cohorts) and fixed doses of LV (90 mg/d). UFT and LV were given 5 days per week concurrently with radiation to 50 Gy (2 Gy/fraction). RESULTS: Twenty-five patients were treated, and 22 received the planned treatment. Three patients were withdrawn from treatment, two due to disease-progression and one due to toxicity. The MTD of UFT with radiation was 400 mg/m(2)/d with 90 mg/d of LV. Diarrhoea was the main dose limiting toxicity (DLT). Since some toxicity (3/12 DLTs) was seen in the expanded cohort at the level below, but none (0/9 DLT) at the starting level, the recommended dose chosen for further testing is 300-350 mg/m(2)/d depending upon the size of the target volume. CONCLUSION: Concomitant chemoradiation with oral UFT plus LV is feasible and well tolerated and should be further investigated since tumour responses were frequently seen.

Irinotecan combined with bolus 5-fluorouracil and folinic acid Nordic schedule as first-line therapy in advanced colorectal cancer.

BACKGROUND: This multicentre phase II study evaluated the efficacy and safety of irinotecan combined with the Nordic schedule of 5-fluorouracil (5-FU) and folinic acid (FA) as first-line therapy in patients with advanced colorectal cancer. PATIENTS AND METHODS: Seventy-four patients with measurable disease and a WHO performance status of 2 or less were treated with irinotecan 210 mg/m(2) as a 30-90 min intravenous infusion on day 1, followed by 5-FU 500 mg/m(2) and FA 60 mg/m(2) bolus on days 1 and 2, every 2 weeks, until disease progression or unacceptable toxicity. The primary end point was the objective response rate. RESULTS: Twenty-nine out of 68 evaluable patients achieved a complete (n = 7) or partial (n = 22) response, leading to an overall response rate of 43% [95% confidence interval (CI) 31% to 55%]. The median duration of response was 10 months. The estimated median time to progression and survival were 6.4 months (95% CI 5.4-9.0) and 15.6 months (95% CI 13.3-19.0), respectively, in the intention-to-treat population. A total of 860 cycles were administered to 74 patients. Neutropenia was the main adverse event with grade 3-4 toxicity in 66% of patients and 17.5% of cycles. Grade 3-4 non-haematological toxicities were infrequent and included diarrhoea in 16% of patients and 2% of cycles and nausea/vomiting in 10% of patients and 1% of cycles. CONCLUSIONS: Irinotecan combined with the bolus Nordic schedule of 5-FU/FA is active in advanced colorectal cancer with an easily managed safety profile which ensures good schedule compliance. The low incidence of grade 3-4 non-haematological toxicity justifies the further evaluation of this combination in the context of randomised clinical trials.

Treatment with GM-CSF and IL-2 in patients with metastatic colorectal carcinoma induced high serum levels of neopterin and sIL-2R, an indicator of immune suppression.

Cytokines may enhance the effect of therapeutic monoclonal antibodies (mAb). Granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-2 (IL-2) have been shown to increase ADCC levels. GM-CSF may augment the induction of an idiotypic network response (anti-tumour immunity). The clinical anti-tumour effect of a combination of mouse mAb17-1A-1A [anti-colorectal carcinoma (CRC)], and GM-CSF was, however, not enhanced by the addition of IL-2. In the present study, some immune functions considered to be involved in mAb-mediated tumour cell killing were analysed in patients receiving GM-CSF and GM-CSF/IL-2 respectively together with the mAb17-1A-1A. Ten patients received mAb17-1A and GM-CSF, and ten patients mAb17-1A with GM-CSF and IL-2. During a 10- day cytokine treatment period, a significantly higher increase in white blood cell counts was noted in the GM-CSF/IL-2 treatment group as compared to GM-CSF-treated patients. In the GM-CSF/IL-2 group, significantly higher serum concentrations of neopterin and soluble IL-2 receptor (sIL-2R) respectively were induced as compared to GM-CSF-treated patients. However, the ADCC of peripheral blood mononuclear cells (PBMC) against a CRC cell line was significantly higher in the GM-CSF group than in the GM-CSF/IL-2 group. The frequencies of patients developing human anti-mouse antibodies (HAMA) and anti-idiotypic antibodies were the same in both groups, while serum concentrations were significantly lower in the GM-CSF/IL-2 group as compared to the GM-CSF group. GM-CSF/IL-2 therapy seems to induce an immune suppressive stage compared to GM-CSF alone affecting cytotoxic mononuclear cells and B cells, which might be mediated through the neopterin metabolic pathway or other inducible immune suppressive factors such as reactive oxygen and nitrogen intermediates.

Incidence of GM-CSF antibodies in cancer patients receiving GM-CSF for immunostimulation.

We have assessed the immunogenicity profile of GM-CSF in patients with either colorectal carcinoma (CRC) at different stages of disease or with multiple myeloma who were given recombinant human GM-CSF (Escherichia coli-derived) combination therapy. Metastatic CRC patients received a colon carcinoma-reactive antibody and high doses of GM-CSF (425--500 microg/day for 10 days), while other CRC patients and those with myeloma received low doses of GM-CSF (75--80 microg/day for 4 days) as an adjuvant along with appropriate tumor antigens. We found that 55% of the patients (11/20) given high doses of GM-CSF developed GM-CSF-reactive antibodies in comparison with an incidence of only 16% (4/25) in patients given low doses of GM-CSF. None of the patients developed neutralizing antibodies and so the biological effects of GM-CSF were not compromised. A majority of patients (80%) (36/45) also developed antibodies to E. coli proteins that were present as trace contaminants in the GM-CSF product. Treatment with recombinant GM-CSF products, therefore, may induce antibodies against this cytokine depending on the regimen and the amounts used. In this study, multiple immunizations with low doses of GM-CSF was associated with a low incidence of GM-CSF antibodies, which did not neutralize the effect of the cytokine. This therapeutic strategy was effective in inducing adjuvant-type effects and needs to be explored in further clinical trials with this cytokine.

Ga733/EpCAM as a target for passive and active specific immunotherapy in patients with colorectal carcinoma.

GA733/EpCAM is an oncofetal antigen abundantly expressed in colorectal carcinoma. This antigen can spontaneously induce a humoral and cellular antitumor immunity and may therefore be a suitable target structure for immunotherapy. Patients with advanced colorectal carcinoma have been treated with monoclonal antibodies (MAb17-1A) against this structure. The data indicate that the chimeric variant was not superior to the original mouse MAb. Addition of cytokines and chemotherapeutics may improve the therapeutic effect of the MAb. A particularly interesting regimen is a combination of MAb17-1A/GM-CSF/alpha-IFN/5-Fu. The GA733 protein antigen can also be used as a vaccine. Patients with colorectal carcinoma stages B and C were vaccinated with this protein antigen in combination with GM-CSF as an adjuvant cytokine. A strong type I T cell response was induced that seemed to be MHC class I as well as class II restricted. No systemic side effects were noted.

Augmentation of the immune response with granulocyte-macrophage colony-stimulating factor and other hematopoietic growth factors.

Granulocyte-macrophage colony-stimulating factor is by far the most widely used hematopoietic growth factor to augment immune responses. At present, the best secured effect is as an adjuvant cytokine for vaccination. Granulocyte-macrophage colony-stimulating factor can be delivered as gene-transduced tumor cells, as plasmid DNA, or as the soluble free granulocyte-macrophage colony-stimulating factor protein. Granulocyte-macrophage colony-stimulating factor must be present at the same site as the vaccine component. Granulocyte-macrophage colony-stimulating factor may also augment the effect of therapeutic monoclonal antibodies by enhancing various effector functions such as antibody-dependent cellular cytotoxicity and amplifying an idiotypic network response (i.e., antitumor immunity). It may also be advantageous to combine granulocyte colony-stimulating factor with monoclonal antibodies (neutrophil and monocyte antibody-dependent cellular cytotoxicity) for tumor therapy. However, these growth factors might also induce immune suppression, which may hamper the contemplated effect of the growth factor. It is urgently warranted to better understand these dual effects on the immune system so that we can find optimal uses for the growth factors in various clinical settings.

Immunopathology of metastases in patients of colorectal carcinoma treated with monoclonal antibody 17-1A and granulocyte macrophage colony-stimulating factor.

Twenty patients with metastatic colorectal carcinoma were treated with a single infusion (400 mg) of a mouse monoclonal antibody (IgG2a) against the tumor-associated antigen CO 17-1A and with a daily injection of granulocyte macrophage colony-stimulating factor (GM-CSF) for 10 days. The cycle was repeated every month. Metastases from 5 of the 20 patients biopsied on days 1 and 10 of the first two treatment cycles were studied by immunohistochemistry. During treatment, neutrophils, monocytes, and T lymphocytes increased concordantly in the tumor as in the blood of the individual patient. Macrophages (CD68) and CD8+ T cells infiltrated the tumor glands and displayed TIA-1-reactive cytotoxic granules. Neutrophils were seen mainly in areas of necrosis. Activated (HLA-DR+) CD4+ T cells were usually abundant in the stroma. During treatment, few natural killer cells were found in the tumor, contrary to the marked increase seen in blood. Our observations indicate that GM-CSF markedly recruited activated, tumor-infiltrating leukocytes, possibly representing antibody-dependent cellular cytotoxicity and cytotoxic T effector cells. The notion that combined antibody and GM-CSF therapy may also promote a T-cell antitumor response is further supported and advocated by our findings. The study lends further support to combining GM-CSF with monoclonal antibody-based therapy.

Multiple primary malignant tumors in a national cancer registry--reliability of reporting.

During the years 1958-1988, 808,522 individuals were registered in the Swedish national population-based cancer register with a total of 933,900 primary malignant tumors. Roughly 11% of the tumors reported to the Swedish Cancer Registry in 1988 were found in persons earlier registered for another primary malignancy. One hundred of the individuals registered with multiple primary malignant tumors were randomly selected for a study of the reliability of reporting of multiple malignancies. Medical records and when necessary histopathological slides and other relevant diagnostic material for each malignancy were collected and the diagnoses reevaluated. Three persons had to be excluded; thus 97 cases with 209 reported malignancies were analysed. Of these, 94% of the first, 98% of the second and 79% of the third malignancy were accepted. Twelve of the reported tumors were not accepted as malignant, five were benign or cancer in situ, five were incorrectly reported as new primaries and two were a second incorrect registration of a previously registered malignancy. All 97 persons had at least one malignant tumor, in 90% of the persons all reported diagnoses were accepted and 93% had multiple primary malignancies. The results of this quality control study indicate that suitable data are available in the Swedish Cancer Registry for investigations related to the occurrence of multiple primary malignancies in a large unselected population. The Swedish Cancer Registry, to which all newly diagnosed malignancies by law have to be reported, comprise today close to one million individuals with registered malignancies.

Humoral anti-idiotypic and anti-anti-idiotypic immune response in cancer patients treated with monoclonal antibody 17-1A.

A group of 96 patients with advanced colorectal carcinoma were treated with the mouse (m) or chimeric (c) (mouse variable regions x human IgG1 constant regions) monoclonal antibody (mAb) 17-1A recognizing the tumour-associated antigen GA733-2. Eighty-two of the 83 patients treated with mmAb 17-1A and 69% of the patients given cmAb17-1A (n = 13) developed anti-idiotypic antibodies (ab2). Auto-antibodies binding to tumour cells expressing GA733-2 were found in 7% of the patients. In a further 38 patients (40%) antitumour-cell antibodies, i.e. anti-anti-idiotypic antibodies (ab3), were induced by the mAb17-1A therapy. Patients with detectable ab3 after treatment had significantly higher ab2 levels than those not developing ab3. Addition of granulocyte/macrophage-colony-stimulating factor (GM-CSF) to mmAb17-1A significantly enhanced the induction of ab2 as well as induction of anti-anti-idiotypic antibodies (ab3) compared to mmAb17-1A alone. Patients with a high increase in antitumour-cell antibodies (ab3) induced by the therapy lived significantly longer than patients with no or a low level of induction of ab3 (P = 0.016). The results indicate that induction of an idiotypic network response might be an important effector mechanism in mAb therapy.

Lung cancer.

This synthesis of the literature on radiotherapy for lung cancer is based on 80 scientific articles, including 2 meta-analyses, 29 randomized studies, 19 prospective studies, and 21 retrospective studies. These studies involve 28172 patients. Basic treatment for limited-stage small cell lung cancer (SCLC), is chemotherapy. Addition of radiotherapy to the primary tumor and mediastinum reduces local recurrence, prolongs long-term survival, and is often indicated. Current, and future, studies can be expected to show successive improvements in results for SCLC by optimizing the combination of radiotherapy and chemotherapy. Should these treatments be given simultaneously or sequentially, and in which order? Which fractionation is best? Probably, no change in resource requirements for radiotherapy will be necessary, with the possible exception of changes in fractionation. Surgery constitutes primary treatment for nonsmall cell lung cancer (NSCLC) stages I and II. Radiotherapy may provide an alternative for patients who are inoperable for medical reasons. The value of radiotherapy following radical surgery for NSCLC remains to be shown. It is not indicated based on current knowledge. For NSCLC stage III, radiotherapy shrinks tumors and prolongs survival at 2 and 3 years. Whether it influences long-term survival after 5 years has not been shown. Considering the side effects of treatment, one must question whether limited improvements in survival motivate routine radiotherapy in these patients. Earlier attempts to add chemotherapy to radiotherapy to improve treatment results of NSCLC have not yielded convincing results. Several studies are currently on-going. Prophylactic cranial irradiation (PCI) greatly reduces the risk for brain metastases from SCLC. However, it has little influence on survival. Many treatment centers give PCI to SCLC patients who have achieved complete remission. This practice may be questioned since PCI is associated with serious complications. PCI is not indicated in patients with NSCLC. In SCLC, where the disease is extensive, only palliative radiotherapy is appropriate. Radiotherapy is an important treatment alternative in special palliative situations involving severe cough, severe bleeding, pain, pulmonary obstructions, and vena cava superior syndrome. In these situations, good results may be achieved with few fractions.

Prostate cancer.

This synthesis of the literature on radiotherapy for prostate cancer is based on 53 scientific articles, including 4 randomized studies, 3 prospective studies, and 44 retrospective studies. These studies involve 52005 patients. The literature provides no apparent evidence to motivate radiotherapy, or any treatment, for highly differentiated T0 tumors. Some findings suggest that radiotherapy or surgery may be indicated for poorly differentiated tumors. The literature however shows no differences in tumor effects between these two methods for treating T0 tumors. Radiotherapy is milder and less mutilating. Conclusions cannot be drawn from the literature concerning whether surgery (radical prostatectomy) or external radiotherapy is preferable for T1 and T2 tumors. Most probably, some patients are more suitable for surgery, others for radiotherapy. More patients are, nevertheless, candidates for radiotherapy. The value of external radiotherapy for T3 tumors is documented. Radiotherapy is valuable as palliative treatment for T4 tumors. Radiotherapy may be valuable as localized, symptom-relieving treatment for generalized prostate cancer. Treatment given via a few high fractions saves patients' time, hospitalization, and resources. Concerning individualized treatment, the differentiation grade is important for the choice of treatment method, mainly in early, but even in late clinical stages. This may involve choosing between radiotherapy and endocrine therapy, or even choosing between radiotherapy and surgery. The value of external radiotherapy increases as the differentiation grade of the tumor decreases. It is essential to treat patients at facilities that have the diagnostic potential to establish the differentiation grade of tumors. The value of postoperative radiotherapy has not yet been demonstrated at any clinical stage of prostate cancer. Treatment results from interstitial brachytherapy alone appear to be clearly inferior to the results from other methods. The value of combining interstitial/external radiotherapy should be studied further.