Radiotherapy-induced lymphocytopenia: changes in total lymphocyte count and in lymphocyte subpopulations under pelvic irradiation in gynecologic neoplasms

Lymphocytopenia is one of the most negative biological prognostic factors in cancer patients. Lymphocytopenia may depend on tumor progression, or on various anticancer therapies. In particular, radiotherapy (RT) may induce direct lymphocyte damage. The present study was carried out to evaluate the influence of pelvic irradiation on lymphocyte number and lymphocyte subpopulations in patients with gynecologic tumors. The study included 40 patients affected by locally limited or advanced uterine tumors, who underwent pelvic irradiation for a total dose of 50.4 Gy. RT induced a significant decline in total lymphocyte number, with values lower than 500/mm3 in 29/40 (73%) patients and with a mean decrease of 71 +/- 4%. In the same way, T lymphocyte, CD4, CD8 and NK cell mean numbers significantly decreased under RT. The decline in NK and CD8 cells was limited to the first 2-3 weeks of irradiation, whereas that involving T lymphocytes and CD4 cells was progressive and persistent until the end of RT. Finally, the decline in total lymphocyte number was significantly greater in patients who had no tumor regression in response to RT. This study confirms that pelvic RT may induce severe lymphocytopenia which could negatively influence the efficacy of RT itself.     

Direct endolymphatic instillation (ELI) of BCG-Tumor cell mixture

Summary A method of active immunization by direct Endolymphatic Instillation (ELI) of a mixture of BCG and Autologous Irradiated Tumor Cells (AITC) is described. ELI was performed in 36 patients with advanced breast cancer, melanoma and some other solid tumors. The procedure was well tolerated and was not associated with any untoward systemic side effects other than those often encountered in conventional BCG immunotherapy. Exposure of patients to AITC by the direct endolymphatic route proved to be superior to immunization by the intradermal route as judged by the subsequent induction of cutaneous Delayed Hypersensitivity Reaction (DHR) toward AITC. When employed as the first immunization attempt ELI was effective in 5 of 6 patients. It led to invigoration of preexisting weak DHR in 6 of 8 patients. In 15 of 22 patients conversion to a strongly positive cutaneous DHR to AITC was achieved by ELI, where previous attempts of immunization by the intradermal route had failed to elicit a positive response. Acquisition of positive cutaneous response to AITC following ELI was found to correlate with favourable prognosis in terms of longer median survival. The effect of ELI was particularly notable with respect to enhancement of in vitro lymphocyte stimulation by PPD antigen, but was not followed by increased reactivity of other in vitro parameters of cell-mediated immunity such as peripheral lymphocyte count, proportion of E-rosette forming cells, and PHA lymphocyte stimulation.Abbreviations used: ELI — Endolymphatic Instillation; AITC — Autologous Irradiated Tumor Cells; BCG — Bacillus Calmette-Guérin; DHR — Delayed Hypersensitivity Reaction; PPD — Purified Protein Derivative (tuberculin); PHA — Phytohemagglutinin; SI — Stimulation Index; E-RFC — E-Rosette Forming Cells; PBL — Peripheral Blood Lymphocytes.     

食管癌患者放射治疗中照射体积和时间与外周血淋巴细胞绝对值的相关性研究

摘要 目的：探究照射体积和时间与食管癌患者外周血淋巴细胞绝对值的相关性。方法：本研究方案将纳入2019年1月~2019年12月蚌埠医学院第一附属医院放疗科收治的放疗或同步放化疗食管癌患者84例,其中单独放疗患者24例,同步放化疗患者60例,采用血液细胞分析仪测定患者放疗期间每周复查外周血白细胞（WBC）、中性粒细胞（N）、淋巴细胞（L）、血红蛋白（HB）及血小板（PLT）计数等指标。Pearson相关性分析照射时间、剂量及体积与外周血指标之间的相关性。结果：食管癌放疗患者,包括同步放化疗及单纯放疗亚组,在治疗1-6周,照射时间与外周血指标均无相关性（P>0.05）。但在放疗第5-6周,患者放疗剂量与WBC、N、L、HB呈负相关（P<0.05）,同步放化疗亚组患者照射剂量与WBC、N、L、HB呈负相关（P<0.05）。在治疗1-4周,不同照射剂量下各梯度照射剂量对应照射体积与外周血指标均无相关性（P>0.05）。但在第5-6周时,患者不同梯度照射剂量下各照射体积与WBC、N呈负相关（P<0.05）,同时在20Gy-60Gy照射剂量,尤其20Gy和30Gy照射剂量下照射体积与L呈负相关（P<0.05）。同步放化疗亚组患者不同照射剂量下各照射体积与WBC、N呈负相关（P<0.05）,同时在20Gy-60Gy照射剂量下照射体积与L呈负相关（P<0.05）,而且在60Gy照射剂量下照射体积与HB呈负相关（P<0.05）。结论：放疗患者特别是同步放化疗亚组患者照射体积、照射剂量与食管癌患者外周血淋巴细胞计数成负相关,基线淋巴细胞与食管癌患者外周血淋巴细胞计数成正相关,而照射时间与食管癌患者外周血淋巴细胞计数无相关性。     

Dose-dependent hyporreactivity to phytohemagglutinin in systemic lupus erythematosus

The response of peripheral blood lymphocytes to stimulation with optimal and suboptimal doses of PHA was measured in patients with active SLE before initiation of therapy. The [³H]thymidine uptake of SLE patient's lymphocytes was significantly lower than that of their matched controls when cells were stimulated with suboptimal PHA doses in the presence of autologous plasma. A moderate improvement in the PHA response was observed by culturing washed patient's lymphocytes in medium supplemented with pooled normal human plasma, but only in one case the response reverted to normal values. A significant inhibitory effect of SLE plasma on the response of normal donor's lymphocytes to stimulation with low PHA doses, which was independent from the presence of lymphocytotoxic antibodies and persisted after complement inactivation was observed in further experiments.The results indicate that depression of lymphocyte transformation could be demonstrated in patients with active SLE using suboptimal doses of PHA and suggest that this depression may be caused by both a defect in the responding lymphocyte populalation and the presence of inhibitory factor(s) in SLE plasma.     

The need for immune evaluation prior to thymosin-containing chemoimmunotherapy for melanoma

Summary In an attempt improve the response to BCG or BCG + DTIC therapy in Stage IIIB melanoma patients, we added thymosin treatment with repeated doses of 4 mg/m² or 40 mg/m². Twenty-eight patients were clinically and immunologically evaluable. Pretreatment immunological evaluation consisted of determination of delayed-type hypersensitivity to recall antigens, enumeration of E-rosettes in blood, and measurement of blood lymphocyte response to phytohemmagglutinin (PHA) and concanavalin A (Con-A). The disease-free interval was correlated with thymosin dose and parameters of immunocompetence. Immunocompetent melanoma patients treated with a high thymosin dose and BCG relapsed earlier than those treated with a low thymosin dose and BCG. Thus, 72% of the melanoma patients who had a PHA SI50 and were treated with 4 mg thymosin/m², were disease-free at 9 months, compared with only 31% of those treated with 40 mg/m² (P=0.02). When the dermatophytin delayed hypersensitivity response (>10 mm induration) was used as a parameter of immunocompetence, 86% of the patients treated with 4 mg/m², were disease-free at 9 months, as against 28% of patients treated with 40 mg thymosin/m² (P=0.07). None of the immunoincompetent patients on high thymosin dose relapsed (0/3). The results suggest that while a high thymosin dose (40 mg/m²) may be detrimental to immunocompetent patients, it may have a beneficial effect in immunoincompetent patients. A low thymosin dose is probably not detrimental to immunocompetent melanoma patients in this study. Monitoring of the immune status prior to and during the use of thymosin in cancer immunotherapy is mandatory.This paper was presented at the Thirteenth Annual Meeting of the American Society for Clinical Oncology, Denver, 1977     

Phase II Trial of Cetuximab and Conformal Radiotherapy Only in Locally Advanced Pancreatic Cancer with Concurrent Tissue Sampling Feasibility Study

BACKGROUND: Preclinical data have indicated the anti-epidermal growth factor receptor (EGFR) agent cetuximab (Erbitux) as a radiosensitizer in pancreatic cancer, but this has not been specifically addressed in a clinical study. We report the results of an original study initiated in 2007, where cetuximab was tested with radiotherapy (RT) alone in locally advanced pancreatic cancer in a phase II trial (PACER). METHODS: Patients (n = 21) received cetuximab loading dose (400 mg/m2) and weekly dose (250 mg/m²) during RT (50.4 Gy in 28 fractions). Toxicity and disease response end point data were prospectively assessed. A feasibility study of on-trial patient blood and skin sampling was incorporated. RESULTS: Treatment was well tolerated, toxicity was low; most patients (71%) experienced acute toxicities of grade 2 or less. Six months posttreatment, stable local disease was achieved in 90% of evaluable patients, but only 33% were free from metastatic progression. Median overall survival was 7.5 months, actuarial survival was 33% at 1 year and 11% at 3 years, reflecting swift metastatic progression in some patients but good long-term control of localized disease in others. High-grade acneiform rash (P = .0027), posttreatment stable disease (P = .0059), pretreatment cancer antigen 19.9 (CA19.9) level (P = .0042) associated with extended survival. Patient skin and blood samples yielded sufficient RNA and good quality protein, respectively. CONCLUSIONS: The results indicate that cetuximab inhibits EGFR-mediated radioresistance to achieve excellent local control with minimal toxicity but does not sufficiently control metastatic progression in all patients. Translational studies of patient tissue samples may yield molecular information that may enable individual treatment response prediction.     

Survival Impact of Delaying Postoperative Radiotherapy in Patients with Esophageal Cancer

The purpose of the current study was to retrospectively assess the effect of postoperative radiotherapy (RT) delay on survival for patients with esophageal cancer. From 2008 to 2011, patients with esophageal cancer who had undergone postoperative RT in five different hospitals in China were reviewed. Clinical data, including time interval between surgery to RT, were prospectively collected. Kaplan-Meier method was conducted to estimate the effect of each variable on progression-free survival (PFS) and overall survival (OS), with differences assessed by log-rank test. Univariate Cox proportional-hazards models were performed for both PFS and OS for all assumed predictor variables. Statistically significant predictor variables (P < .05) on univariate analysis were then included in multivariate Cox proportional-hazards models, which were performed to compare the effects of RT delay on PFS and OS. A total of 316 patients were finally enrolled in this prospectively multicentric study. Time to RT after surgery varied from 12 days to over 60 days (median, 26 days). Multivariate analysis showed that delay to RT longer than the median does not appear to be a survival cost. There was also no statistically difference in PFS (P = .513) or OS (P = .236) between patients stratified by quartiles (≤21 days vs ≧35 days). However, patients with particularly long delays (≧42 days) demonstrated a detrimental impact on OS (P = .021) but not PFS (P = .580). Delaying postoperative RT of esophageal cancer does not impact PFS, but results in a significant reduction on OS if delaying longer than 6 weeks.     

Immunotherapy of breast cancer,malignant melanoma,and acute leukemia with BCG: Prolongation of disease free interval and survival

Summary Results of immunotherapy with BCG in patients with malignant melanoma, breast cancer, and acute leukemia are described. The first study demonstrated that high doses of living BCG organisms (6×10⁸ viable units) delivered by scarification in the upper arms and legs prolonged the disease-free interval and survival of 52 malignant melanoma patients with regional lymph node metastases compared to 218 comparable surgical control patients. Patients with trunk and extremity, but not head and neck melanoma, benefited from BCG, suggesting the importance of the delivery of BCG into the tumor-involved lymphatics.The second study evaluated the therapeutic efficacy of living BCG organisms by scarification in a group of adult acute leukemia patients after the cessation of chemotherapy. Thirty-seven patients had been in remission on intermittent chemotherapy for 12–24 months. Following late intensive consolidation chemotherapy, 7 consecutive patients received no further therapy and then 30 consecutive patients received BCG. Patients maintained on BCG have had a prolonged disease-free interval compared to those given on no further therapy (P=0.07) or compared to a group of similar patients maintained on chemotherapy alone (P=0.001). Similarly, the survival has been improved for patients maintained on BCG compared to those left unmaintained (P=0.009), or those maintained on chemotherapy (P=0.001).The principles of intermittent chemotherapy combined with BCG immunotherapy, first developed in patients with disseminated melanoma and acute myelogenous leukemia, have been confirmed in a series of patients with disseminated breast cancer. Forty-five patients treated with a combination of 5-FU, adriamycin, and cyclophosphamide (FAC) plus BCG by scarification showed prolongation of remission as well as survival compared to a comparable group of 44 patients treated with FAC chemotherapy without immunotherapy. Thus, 23/44 patients treated with FAC have died (median=14 months) compared to only 5/45 patients on FAC-BCG (median=12⁺ months), P=0.005. The limitations of BCG immunotherapy as well as speculations for future developments of immunotherapy are discussed.This work was supported by Contract No1-CB 33888 from the National Institutes of Health, Public Health Service, Bethesda, Maryland 20014. Drs. Gutterman and Mavligit are the recipients of Career Development Awards (Ca 71007-02 and CA 00130-01, respectively) from the National Institutes of Health, Education, and Welfare, Bethesda, Maryland 20014.     

Rapid effects of BCG on T cell function in cancer patients

Summary Forty-four cancer patients were evaluated with multiple sequential tests to determine the effects of a single intracutaneous injection of BCG on the levels of total and high-affinity sheep erythrocyte-forming cells and on lymphoproliferative responses to a T cell mitogen (PHA) and antigens (MLC and PPD). The analysis of the data was complicated by considerable pretreatment variation in the results with some patients and by the lack of a consistent change in responses among all patients. However, exploratory statistical procedures made it possible to demonstrate that inoculation with BCG was associated with a significant transient increase, on day 3 post-injection, in levels of total and active rosette-forming cells and in lymphoproliferative responses to PPD. The effects on responses to PHA varied with the level of pretreatment reactivity with patients with initial low responses showing a significant increase on days 3 and 7 and patients with initial normal responses showing a significant decrease on days 3 and 7. Patients and normal individuals receiving no injection, and patients receiving isotonic saline injections, showed none of these changes. Thus it appears that BCG may cause measurable changes in T cell levels and lymphoproliferation to T cell mitogen (PHA) and antigen (PPD).     

Brain Radiotherapy plus Concurrent Temozolomide versus Radiotherapy Alone for Patients with Brain Metastases: A Meta-Analysis

Objective

We performed a meta-analysis of randomized clinical trials to compare the efficacy of brain radiotherapy (RT) combined with temozolomide (TMZ) versus RT alone as first-line treatment for brain metastases (BM).

Methods

Medline, Embase, and Pubmed were used to search for relevant randomized controlled trials (RCTs). Two investigators reviewed the abstracts and independently rated the quality of trials and relevant data. The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), objective response rate (ORR), and adverse events.

Results

Seven studies were selected from the literature search. RT plus TMZ produced significant improvement in ORR with odds ratio (OR) of 2.27 (95% CI, 1.29 to 4.00; P = 0.005) compared with RT alone. OS and PFS were not significantly different between the two arms (OS: HR, 1.00; P = 0.959; PFS: HR, 0.73; P = 0.232). However, the RT plus TMZ arm was associated with significantly more grade 3 to 4 nausea and thrombocytopenia.

Conclusion

Concomitant RT and TMZ, compared to RT alone, significantly increases ORR in patients with BM, but yields increased toxicity and fails to demonstrate a survival advantage.     

Modulation of lymphocyte mitogen responses by cocultured fibroblasts

Immunological reactions in vivo occur in an environment rich in fibroblasts (FB) and other connective tissue cells. The possibility that FB might affect mononuclear cell proliferative responses to mitogens in vitro was examined in a microculture system. Human peripheral blood mononuclear cells (MC) were cocultured with mitomycin C-treated FB in the presence of phytohemagglutinin (PHA) or pokeweed mitogen (PWM). Cocultured FB (at a 1:100 to 1:10 FB:MC ratio) suppressed the response of MC to PHA (by as much as 35%) but did not significantly affect PWM responses. Cocultures of FB and MC were characterized by 10- to 30-fold increases in prostaglandin E₂ concentrations compared to MC or FB cultured alone. Inhibition of prostaglandin synthesis with indomethacin or mefenamic acid significantly reversed the FB-mediated suppression of lymphocyte PHA responses. Prostaglandin-dependent FB suppression of lymphocyte PHA responses was seen only when FB:MC coculture was initiated at the onset of exposure of MC to PHA. When FB were added to MC after 24 hr of culture with PHA, no effect was seen. Addition at 48 or 66 hr resulted in prostaglandin-independent enhancement of lymphocyte proliterative responses to PHA. Thus in cocultures of FB and MC, MC reactivity to PHA may be influenced in part via alterations in FB prostaglandin metabolism. The interaction between FB and MC may be important in the modulation of immune responses in inflammatory lesions.     

Is There a Benefit in Receiving Concurrent Chemoradiotherapy for Elderly Patients with Inoperable Thoracic Esophageal Squamous Cell Carcinoma?

Background and purpose

The benefit of concurrent chemoradiotherapy (CCRT) in elderly patients with inoperable esophageal squamous cell carcinoma (SCC) is controversial. This study aimed to assess the efficiency and safety of CCRT in elderly thoracic esophageal cancer patients.

Methods and materials

Between January 2002 and December 2011, 128 patients aged 65 years or older treated with CCRT or radiotherapy (RT) alone for inoperable thoracic esophageal SCC were analyzed retrospectively (RT alone, n = 55; CCRT, n = 73).

Results

No treatment-related deaths occurred and no patients experienced any acute grade 4 non-hematologic toxicities. Patients treated with CCRT developed more severe acute toxicities than patients who received RT alone. The 3-year overall survival (OS) rate was 36.1% for CCRT compared with 28.5% following RT alone (p = 0.008). Multivariate analysis identified T stage and treatment modality as independent prognostic factors for survival. Further analysis revealed that survival was significantly better in the CCRT group than in the RT alone group for patients ≤ 72 years. Nevertheless, the CCRT group had a similar OS to the RT group for patients > 72 years.

Conclusion

Our results suggest that elderly patients with inoperable thoracic esophageal SCC could benefit from CCRT, without major toxicities. However, for patients older than 72 years, CCRT is not superior to RT alone in terms of survival benefit.     

X-irradiation of equine peripheral blood lymphocytes stimulated with phytohaemagglutinin in vitro.

Small lymphocytes were isolated from the peripheral blood of horses and incubated at 37 degrees C in Eagle's medium supplemented with 20 per cent foetal calf serum. The addition of phytohaemagglutinin (PHA) to the cultures resulted in: increased RNA and protein synthesis; the enlargement of the small lymphocyte into a lymphoblast-like cell; the initiation of DNA synthesis, and cell division. When survival was measured 24 hours after X-irradiation by means of phase-contrast microscopy, the lymphoblast-like cell was much more radio-resistant (D0 = 250 rad) than the small lymphocyte (D0 = 20 rad). This increase in radioresistance, however, was not observed until 12-24 hours after PHA treatment. To investigate which of the changes occurring during the transformation of the small lymphocyte was responsible for the increased resistance to irradiation, the percentage of cells surviving irradiation was compared with the percentage of cells incorporating significant amounts of 3HTdR, 3H-UR, or 3H-leucine at the time of irradiation. For this comparison, a dose of 100 rad was used because 100 rad killed essentially all of the small lymphocytes, but less than 35 percent of the cells which had become radioresistant from the PHA treatment. The results indicated that the increase in radioresistance was not associated with DNA synthesis, but instead correlated with the increase in RNA and protein synthesis which the cells had attained at the time of irradiation.     

Relationship between the capacity to be stimulated of lymphocyte subpopulations and the RAI staging in patients with chronic lymphocytic leukemia]

By means of the incorporation rate of 3H thymidine into the lymphocytes of patients with chronic lymphatic leukaemia the possibility of stimulating them by using different mitogens was checked and compared with normal persons. The examination covered 11 patients treated with extracorporeal irradiation of the blood (ECIB), 5 patients treated with a chlorambucil therapy, and 10 untreated patients who were classified according to the staging system proposed by RAI. The lymphocytes of the peripheral blood were stimulated as mixed and isolated T and B-lymphocytes in the microculture by using the mitogens PHA, PWM, ConA, and LPS. In all CLL patients there was a diminished stimulation rate of a mixed lymphocyte population. A relation existed between the seriousness of the stage and the diminution of the incorporation rate of 3H thymidine. A corresponding correlation could not be identified in untreated CLL patients. Isolated T-lymphocytes revealed better results of stimulation than the total population. As to their function B-lymphocytes showed a dependance on the kind of therapy. In the mixed lymphocyte culture of normal persons the best findings could be observed after stimulation with PHA, that is also valid for CLL patients. PHA, PWA, ConA, and LPS were suitable as substances stimulating B-lymphocytes with different efficacy in normal persons and CLL patients. Both collectives showed the best results in the T-lymphocyte culture after stimulation with LPS.     

Significant impact on the oncologic outcomes with intensity modulated radiotherapy and conformational radiotherapy over conventional radiotherapy in cervix cancer patients treated with radiotherapy

ObjectiveWe designed a retrospective cohort of women with cervix cancer treated by radiation therapy with an extended follow-up to evaluate if the incorporation of modern radiation techniques was a prognostic factor.Material and methodsWe studied a cohort of patients with cervix cancer FIGO stage I-IVa treated in the last fifteen years. Patients were treated with radiotherapy alone (RT) or chemoradiation alone (CRT) using conventional radiotherapy (2DRT), conformational radiotherapy (3DRT), or intensity-modulated radiotherapy (IMRT) followed by high dose rate brachytherapy. Univariate and multivariate analysis was conducted to identify significant prognostic factors (p < 0.05).Results228 patients with cervix cancer were included. The treatment groups were CRT (64.8%), and RT (34.2%), with 31.6% submitted to 2DRT and 68.4% to IMRT/3DRT. The median follow-up was 6.3 years, the OS in 5 years according to the treatment groups was 48% for CRT, and 27.8% for RT (p < 0.001). The early-stage I-IIa (p = 0.001), CRT, and IMRT/3DRT were significant factors for better overall survival (OS) in the multivariate analysis. For the cancer-specific survival (CSS), chemoradiation, age <60 years, and IMRT/3DRT were significant. Treatment with IMRT/3DRT was the only prognostic factor associated with event-free survival (EFS).ConclusionIn a long-term follow-up, chemoradiation, early-clinical stage, and age <60 years were significant factors associated with better OS and CSS at 5 and 8 years. The incorporation of new radiation techniques, such as IMRT/3DRT, over time has a significant impact on all endpoints (EFS, OS, and CSS) of this cohort. These outcomes are useful to decide about the radiation technique to achieve satisfactory oncological results outside a clinical trial.     

Time-dependent enhancement of lymphocyte activation by mitogens after exposure to isolation or water scheduling

The effects of isolation and water scheduling on mitogen induced lymphocyte proliferation were investigated. Isolated rats were animals which had been raised in group-housed conditions and then transferred to individual cages with ad lib access to water for a 1 or 2 week period. Water scheduled rats were maintained in group housing (5 rats per cage) with ad lib access to food but with access to water for a single 30 minute session each day. Responses of these groups were compared to those of animals which had been continuously group-housed with ad lib access to food and water. No differences in lymphocyte responses to phytohemagglutinin (PHA) were found 1 week after exposure to isolation. However, after 2 weeks, splenic and blood T lymphocytes from isolated animals demonstrated an increased proliferative response to suboptimum and maximum concentrations of PHA. Splenic B lymphocyte responses to lipopolysaccharide (LPS) from isolated animals were also increased by 2- to 3-fold compared to group-housed controls. Two weeks of exposure of animals to daily water scheduling similarly increased the splenic lymphocyte proliferation. This increased responsiveness to PHA was not accompanied by a significant change in the sensitivity of the lymphocytes to PHA, in the total number of white blood cells, or the proportion of splenic T or T helper lymphocytes. Our results show that the increase in lymphocyte proliferation is time-dependent, requires greater than 1 week of exposure to isolation and is due to factors other than changes in sensitivity to mitogen or T lymphocyte number.     

Genotoxic effects of radiotherapy and chemotherapy on the circulating lymphocytes of breast cancer patients. I. Chromosome aberrations induced in vivo

Unstable chromosome aberrations were scored in peripheral blood lymphocytes (PBL) serially collected from 21 breast cancer patients before and after radiotherapy (RT), chemotherapy (CT) and combined treatments. Local radiotherapy as treatment for mammary cancer induced unstable chromosome aberrations in peripheral blood lymphocytes. Only a fraction of these lymphocytes were exposed to irradiation during treatment and the chromosomal damage observed in PBL was equivalent to that induced by irradiation in vitro with 2 Gy at high dose rate, i.e., about 4% of the total dose delivered locally. Chemotherapy alone did not induce such anomalies. Apart from the observed interindividual variations in either the level or the fate of dicentrics with time, different features of chromosome damage were found when chemotherapy was given before or after local cobaltotherapy: secondary chemotherapy did not alter the frequency and the overdispersed distribution of dicentrics observed after first-line radiotherapy; in contrast, when CT was given before radiotherapy, a lower dicentric frequency was scored, the distribution of dicentrics was not always found to be overdispersed and there was a time-dependent decrease in dicentrics after in vivo exposure.     

Immune responses during human schistosomiasis mansoni. VI. In vitro nonspecific suppression of phytohemagglutinin responsiveness induced by exposure to certain schistosomal preparations.

Simultaneous in vitro exposure of human peripheral blood mononuclear cells to phytohemagglutinin-P (PHA) and either soluble schistosomal egg antigenic preparation (SEA) or soluble cercarial antigenic preparation (CAP) obtained from Schistosoma mansoni resulted in decreased responsiveness as compared to exposure to PHA alone. The addition of a soluble adult worm antigenic preparation (SWAP) did not predictably alter PHA responses in this system. The suppression due to in vitro exposure to either SEA or CAP was expressed whether the lymphocyte donors were S. mansoni patients (early infection, chronic, or treated), or uninfected subjects. The degree of suppression was related to the concentration of SEA used, and the timing of exposure. Preexposure to SEA for 3 days before the addition of PHA resulted in more potent suppression. However, a delay in the time of the addition of SEA of 6 and 24 hr after PHA exposure decreased and eliminated, respectively, its suppressive capacity. SEA and CAP were not directly toxic to responding cells, and appeared to exert their nonspecific suppressive influences through T lymphocyte-related mechanisms. It was observed that although these suppressive events could be induced and observed in vitro, the responsiveness of S. mansoni patient lymphocytes to PHA was equal with that of uninfected controls.     

Chemoimmunotherapy of advanced breast cancer: prolongation of remission and survival with BCG.

Forty-five patients with disseminated breast cancer were given a trial of combination chemotherapy consisting of fluorouracil, adriamycin, and cyclophosphamide (FAC) and immunotherapy with BCG given by scarification. The results were compared with those in a comparable group of 44 patients treated with FAC alone immediately before the chemoimmunotherapy study. The remission rates (73% and 76% for FAC and FAC-BCG respectively) were similar in both studies. The durations of remission for patients on FAC-BCG (medium 12 months) were longer than remissions achieved for patients given FAC alone (median 8 months) (P = 0.068). The most notable effect of BCG was on survival. Thus 21 out of 34 patients achieving remission on FAC-BCG were alive at the time of the last follow-up examination (median over 22 months) compared with 11 out of 32 patients achieving remission on FAC (median 15 months) (P = 0.01). Twenty-six of the 45 patients given FAC-BCG were alive at the time of the last follow-up examination (median over 22 months) compared with 12 of the 44 patients given FAC (median 15 months) (P = 0.005). Although the apparent benefit of BCG could be explained by a maldistribution of some prognostic factors, the data suggest that further trial of chemoimmunotherapy of breast cancer should be carried out.     

Active,specific immunotherapy of stage III breast cancer

Summary Active specific immunization with autologous irradiated tumor cells (AITC) admixed with BCG was attempted in 49 stage III breast cancer patients whose median follow-up at present is 3 years. As a first immunizing procedure 41 patients received repeated intradermal inoculations and 8 had a single endolymphatic instillation (ELI). Skin response (SR) to AITC alone was induced after two to nine weekly immunizations. Eight of 41 patients with negative or weak responses were effectively reimmunized by ELI, as indicated by conversion and invigoration of SR. Following immunization, radiotherapy to breast and axilla was administered. Thereafter, fortnightly 5-FU and monthly boosters of AITC-BCG mixture were given for 2 years. Strength of response to AITC induced by active immunization was found to relate to subsequent disease recurrence, with 15% relapsing among the good responders and 53% among the weak and non-responders. Positive SR to AITC — once elicited — was steadily maintained in the majority of patients; its decline was associated with manifest disease recurrence. Conversion to AITC positivity in vivo following specific immunization was not detectable by the LMI assay. Lymphocyte stimulation (MLTI) by AITC in vitro was found in only 9 of 26 tested patients with positive in vivo SR to AITC. Cutaneous response to AITC appears to be the only parameter of antitumor response showing clinical correlation, while specific in vitro correlates of cell-mediated immunity were found unsuitable for monitoring patients undergoing specific immunotherapy. While in vivo PPD response was mainly unchanged or enhanced, in vitro lymphocyte stimulation by PPD and PHA showed a distinct decline at the time of relapse. The cumulative proportion of relapse among the immunotherapy patients at 3 years was 32% with mortality of 12% (13 relapsed, 5 died), both being significantly lower than reported results in stage III breast cancer without immunotherapy. It is concluded that specific immunization with AITC is feasible in most breast cancer patients with loco-regionally advanced disease and that this intervention is conducive to favorable modification of the course of their disease.