Pretreatment plasma TGF beta 1 levels are prognostic for survival but not morbidity following radiation therapy of carcinoma of the cervix

TGFβ1 in Cancer-Associated Fibroblasts Is Associated With Progression and Radiosensitivity in Small-Cell Lung Cancer

Objective

Small-cell lung cancer (SCLC) is aggressive, with early metastasis. Cytokines secreted by cancer-associated fibroblasts (CAFs) within various tumors influences these features, but the function in particular of TGFβ1 (transforming growth factor beta 1) is controversial and unknown in SCLC. This study explored the influence of TGFβ1 in CAFs on the development, immune microenvironment, and radiotherapy sensitivity of SCLC.

Methods

SCLC specimens were collected from 90 patients who had received no treatment before surgery. Tumor and tumor stroma were subjected to multiplex immunohistochemistry to quantitate TGFβ1 and other immune factors in CAFs. Cell proliferation and flow cytometry apoptosis assays were used to investigate associations between TGFβ1 and proliferation and radiotherapy sensitivity. The immune factors in tumors were detected by immunohistochemistry in vitro and in vivo (mice).

Results

TGFβ1 levels on CAFs lower or higher than the median were found, respectively, in 52.2 and 47.8% of patients; overall survival of patients with TGFβ1-high levels (53.9 mo) was significantly longer than that of the TGFβ1-low group (26.9 mo; P = 0.037). The univariate and multivariate analyses indicated that a TGFβ1-high level was an independent predictor of increased survival time. TGFβ1-high levels in CAFs were associated with inhibition of growth, proliferation, antitumor immunity, and enhanced radiotherapeutic sensitivity and tumor immunity of tumor. TGFβ1-low levels promoted tumor cell growth and radiotherapy sensitivity in vivo and in vitro.

Conclusion

High levels of TGFβ1 in CAFs were associated with longer overall survival in patients with SCLC and enhanced radiotherapy sensitivity.

[Inflammatory and immune biomarkers of radiation response]

In radiotherapy, the treatment is adapted to each individual to protect healthy tissues but delivers most of time a standard dose according to the tumor histology and site. The only biomarkers studied to individualize the treatment are the HPV status with radiation dose de-escalation strategies, and tumor hypoxia with dose escalation to hypoxic subvolumes using FMISO- or FAZA-PET imaging. In the last decades, evidence has grown about the contribution of the immune system to radiation tumor response. Many preclinical studies have identified some of the mechanisms involved. In this context, we have realised a systematic review to highlight potential inflammatory and immune biomarkers of radiotherapy response. Some are inside the tumor microenvironment, as lymphocyte infiltration or PD-L1 expression, others are circulating biomarkers, including different types of hematological cells, cytokines and chemokines.

A Novel TGFβ Trap Blocks Chemotherapeutics-Induced TGFβ1 Signaling and Enhances Their Anticancer Activity in Gynecologic Cancers

Purpose: We investigated the mechanisms of how TGFβ pathway is activated by chemotherapeutics and whether a novel TGFβ trap called RER can block chemotherapeutics-induced TGFβ pathway activation and enhance their antitumor activity in gynecologic cancer.Patients and Methods: An unbiased bioinformatic analysis of differentially expressed genes in 31 ovarian cases due to chemotherapy was used to identify altered master regulators. Phosphorylated Smad2 was determined in 30 paired cervical cancer using IHC. Furthermore, the effects of chemotherapeutics on TGFβ signaling and function, and the effects of RER on chemotherapy-induced TGFβ signaling were determined in gynecologic cancer cells.Results: Chemotherapy-induced transcriptome alteration in ovarian cancer was significantly associated with TGFβ signaling activation. Chemotherapy was found to activate TGFβ signaling as indicated by phosphorylated Smad2 in paired cervical tumor samples (pre- and post-chemotherapy). Similar to TGFβ1, chemotherapeutics were found to stimulate Smad2/3 phosphorylation, cell migration, and markers related to epithelial-mesenchymal transition (EMT) and cancer stem cells (CSC). These TGFβ-like effects were due to the stimulation of TGFβ1 expression and secretion, and could all be abrogated by TGFβ inhibitors including a novel TGFβ trap protein called RER both in vitro and in vivo Importantly, combination treatment with RER and cisplatin showed a higher tumor inhibitory activity than either agent alone in a xenograft model of ovarian cancer.Conclusions: Chemotherapeutics can stimulate TGFβ1 production and consequently enhance TGFβ signaling, EMT, and CSC features resulting in reduced chemo-sensitivity. Combination therapy with a TGFβ inhibitor should alleviate this unintended side effect of chemotherapeutics and enhance their therapeutic efficacy. Clin Cancer Res; 24(12); 2780-93. ©2018 AACR.

Transforming growth factor-β1 in carcinogenesis, progression, and therapy in cervical cancer

Transforming growth factor β1 (TGF-β1) is a multifunctional cytokine that plays important roles in cervical tumor formation, invasion, progression, and metastasis. TGF-β1 functions as a tumor inhibitor in precancerous lesions and early stage cancers of cervix whereas as a tumor promoter in later stage. This switch from a tumor inhibitor to a tumor promoter might be due to various alterations in TGF-β signaling pathway, such as mutations or loss of expression of TGF-β receptors and SMAD proteins. Additionally, the oncoproteins of human papillomaviruses have been shown to stimulate TGF-β1 expression, which in turn suppresses host immune surveillance. Thus, in addition to driving tumor cell migration and metastasis, TGF-β1 is believed to play a key role in promoting human papillomavirus infection by weakening host immune defense. In this article, we will discuss the role of TGF-β1 in the expression, carcinogenesis, progression, and therapy in cervical cancers. A better understanding of this cytokine in cervical carcinogenesis is essential for critical evaluation of this cytokine as a potential prognostic marker and therapeutic target.

Radio-induced apoptosis of peripheral blood CD8 T lymphocytes is a novel prognostic factor for survival in cervical carcinoma patients

BACKGROUND AND PURPOSE

A close relationship exists between immune response and tumor behavior. This study aimed to explore the associations between radiation-induced apoptosis (RIA) in peripheral blood lymphocytes (PBL) and clinical pathological variables. Furthermore, it assessed the role of RIA as a prognostic factor for survival in cervical carcinoma patients.

PATIENTS AND METHODS

Between February 1998 and October 2003, 58 consecutive patients with nonmetastatic, localized stage I-II cervical carcinoma who had been treated with radiotherapy (RT) ± chemotherapy were included in this study. Follow-up ended in January 2013. PBL subpopulations were isolated and irradiated with 0, 1, 2 and 8 Gy then incubated for 24, 48 and 72 h. Apoptosis was measured by flow cytometry and the β value, a parameter defining RIA of lymphocytes, was calculated.

RESULTS

Mean follow-up duration was 111.92 ± 40.31 months. Patients with lower CD8 T lymphocyte β values were at a higher risk of local relapse: Exp(B) = 5.137, confidence interval (CI) 95 % = 1.044-25.268, p = 0.044. Similar results were observed for regional relapse: Exp(B) = 8.008, CI 95 % = 1.702-37.679, p = 0.008 and disease relapse: Exp(B) = 6.766, CI 95 % = 1.889-24.238, p = 0.003. In multivariate analysis, only the CD8 T lymphocyte β values were found to be of prognostic significance for local disease-free survival (LDFS, p = 0.049), regional disease-free survival (RDFS, p = 0.002), metastasis-free survival (MFS, p = 0.042), disease-free survival (DFS, p = 0.001) and cause-specific survival (CSS p = 0.028).

CONCLUSION

For the first time, RIA in CD8 T lymphocytes was demonstrated to be a predictive factor for survival in cervical carcinoma patients.

Prognostic cell biological markers in cervical cancer patients primarily treated with (chemo)radiation: a systematic review

The aim of this study was to systematically review the prognostic and predictive significance of cell biological markers in cervical cancer patients primarily treated with (chemo)radiation. A PubMed, Embase, and Cochrane literature search was performed. Studies describing a relation between a cell biological marker and survival in ≥50 cervical cancer patients primarily treated with (chemo)radiation were selected. Study quality was assessed, and studies with a quality score of 4 or lower were excluded. Cell biological markers were clustered on biological function, and the prognostic and predictive significance of these markers was described. In total, 42 studies concerning 82 cell biological markers were included in this systematic review. In addition to cyclooxygenase-2 (COX-2) and serum squamous cell carcinoma antigen (SCC-ag) levels, markers associated with poor prognosis were involved in epidermal growth factor receptor (EGFR) signaling (EGFR and C-erbB-2) and in angiogenesis and hypoxia (carbonic anhydrase 9 and hypoxia-inducible factor-1α). Epidermal growth factor receptor and C-erbB-2 were also associated with poor response to (chemo)radiation. In conclusion, EGFR signaling is associated with poor prognosis and response to therapy in cervical cancer patients primarily treated with (chemo)radiation, whereas markers involved in angiogenesis and hypoxia, COX-2, and serum SCC-ag levels are associated with a poor prognosis. Therefore, targeting these pathways in combination with chemoradiation may improve survival in advanced-stage cervical cancer patients.

Alterations of dendritic cell subsets in the peripheral circulation of patients with cervical carcinoma

Patients with cervical carcinoma (CC) are frequently immunocompromised. Dendritic cells (DCs) are potent antigen-presenting cells. Using multicolor flow cytometry, the percentages of CD11c+ (DC1) and CD123+ (DC2) subsets, were determined in the peripheral blood of 37 patients with cervical carcinoma (CC), 54 patients with CIN, and 62 healthy individuals. A substantial reduction of circulating dendritic cells and accordingly immunodepression may be associated with increased IL-6 and TGF-β in serum. These findings could give expression to the immunosuppression of circulating dendritic cells in patients with CC and CIN, thus, may indicate novel aspects of cervical carcinoma immune evasion.

Serum transforming growth factor-β1 level reflects disease status in patients with esophageal carcinoma after radiotherapy

AIM: To evaluate the relationship between changes in serum transforming growth factor β1 (TGFβ1) level and curative effect of radiotherapy (RT) in patients with esophageal carcinoma.

METHODS: Ninety patients with histologically confirmed esophageal carcinoma were enrolled. Serum samples for TGFβ1 analysis were obtained before and at the end of RT. An enzyme-linked immunosorbent assay was used to measure serum TGFβ1 level. Multivariate analysis was performed to investigate the relationship between disease status and changes in serum TGFβ1 level.

RESULTS: Serum TGFβ1 level in patients with esophageal carcinoma before RT was significantly higher than that in healthy controls (P < 0.001). At the end of RT, serum TGFβ1 level was decreased in 67.82% (59/87) of the patients. The overall survival rate at 1, 3 and 5 years was 48.28% (42/87), 19.54% (17/87) and 12.64% (11/87), respectively. Main causes of death were local failure and regional lymph node metastasis. In patients whose serum TGFβ1 level decreased after RT, the survival rate at 1, 3 and 5 years was 61.02% (36/59), 28.81% (17/59) and 18.64% (11/59), respectively. The survival rate at 1 year was 17.86% (5/28) in patients whose serum TGFβ1 level increased after RT, and all died within 18 mo (P < 0.01).

CONCLUSION: Serum TGFβ1 level may be a useful marker for monitoring disease status after RT in patients with esophageal carcinoma.

The genomics revolution and radiotherapy

The expansion of our knowledge through the Human Genome Project has been accompanied by the development of new high-throughput techniques, which provide extensive capabilities for the analysis of a large number of genes or the whole genome. These assays can be carried out in various clinical samples at the DNA (genome), RNA (transcriptome) or protein (proteome) level. There is a belief that this genomic revolution, i.e. sequencing of the human genome and developments in high-throughput technology, heralds a future of personalised medicine. For clinical oncology, this progress should increase the possibility of predicting individual patient responses to radiotherapy. This review highlights some of the work involving sparsely ionising radiation and the new technologies.

A list of candidate cancer biomarkers for targeted proteomics

We have compiled from literature and other sources a list of 1261 proteins believed to be differentially expressed in human cancer. These proteins, only some of which have been detected in plasma to date, represent a population of candidate plasma biomarkers that could be useful in early cancer detection and monitoring given sufficiently sensitive specific assays. We have begun to prioritize these markers for future validation by frequency of literature citations, both total and as a function of time. The candidates include proteins involved in oncogenesis, angiogenesis, development, differentiation, proliferation, apoptosis, hematopoiesis, immune and hormonal responses, cell signaling, nucleotide function, hydrolysis, cellular homing, cell cycle and structure, the acute phase response and hormonal control. Many have been detected in studies of tissue or nuclear components; nevertheless we hypothesize that most if not all should be present in plasma at some level. Of the 1261 candidates only 9 have been approved as "tumor associated antigens" by the FDA. We propose that systematic collection and large-scale validation of candidate biomarkers would fill the gap currently existing between basic research and clinical use of advanced diagnostics.

Concurrent cisplatin-based chemoradiation for cervical carcinoma: tumor response, toxicity, and serum cytokine profiles

PURPOSE

To evaluate the relation between tumor response, treatment toxicity, and serum cytokine profiles in patients with cervical cancer receiving cisplatin-based chemoradiation.

PATIENTS AND METHODS

Forty-two patients with cervical carcinoma receiving chemoradiation were recruited. Hemogram, biochemistry profile, cytokine levels, tumor size, and toxicity were assessed weekly.

RESULTS

The absolute neutrophil count decreased accompanied by an increase in serum levels of G-CSF during chemoradiation. The sudden elevation of serum TGF-beta 1 and VEGF levels after the first fraction of brachytherapy accompanied with the development of greater radiation therapy (RT) morbidity. Lower pretreatment TGF-beta 1 and VEGF levels are associated with tumor response to chemoradiation.

CONCLUSION

The serial changes in serum cytokines during chemoradiation may correlate with tumor regression and treatment morbidity.

Symptomatic osteoradionecrosis of pelvic bones in patients with gynecological malignancies-result of a long-term follow-up

The aim of this study was to assess the incidence and risk factors of pelvic fractures as a result of radiation therapy in women with gynecological cancer. We retrospectively reviewed 3530 female patients treated at our institute between 1980 and 1998 with megavoltage radiation with or without brachytherapy for cancer in the pelvic area. Eligible were patients with vulvar, vaginal, cervical, endometrial, and fallopian tube cancer. Median follow-up was 88 months (range 0-240). Emphasis was put on treatment-related and patient-related risk factors. Of the eligible 3155 patients, 15 developed symptomatic bone fracture caused by osteoradionecrosis, which makes an overall incidence of 0.44% The diagnosis was based on anamnesis, clinical course, and X-ray or computed tomography images. Median time of onset was 44 months (range 6-197). All patients had pain as the first symptom. The only independent predictive factor for developing osteoradionecrosis seemed to be preexistent osteoporosis. Other risk factors that are related to osteoporosis include higher age, postmenopausal status, or steroid treatment. We did not find any significant treatment-related predictive factor for pelvic osteoradionecrosis. Patients with osteoporosis are probably at the highest risk for developing osteoradionecrotic fractures after pelvic radiotherapy. More studies are needed to find out other endogenous predictive factors.

Prognostic relevance of TGF-beta1 and PAI-1 in cervical cancer

Cervical carcinoma is a human papilloma virus (HPV)-related immunogenic type of malignancy, in which escape of the tumor from the hosts' immune response is thought to play an important role in carcinogenesis. The multifunctional cytokine transforming growth factor-beta(1) (TGF-beta(1)) is involved in immunosuppression, stroma and extracellular matrix formation and controlling (epithelial) cell growth. The plasminogen activating (PA) system plays a key role in the cascade of tumor-associated proteolysis leading to extracellular matrix degradation and stromal invasion. Changes in expression of components of this system, including plasminogen activator inhibitor-1 (PAI-1), have been associated with poor prognosis in a variety of solid tumors. The present study was undertaken to assess the role of both components on relapse, survival and other clinicopathologic parameters in cervical cancer. The expression of TGF-beta(1) mRNA in 108 paraffin-embedded cervical carcinomas was detected by mRNA in situ hybridization. Immunohistochemistry was used to investigate the expression of PAI-1 protein. The presence of cytoplasmatic TGF-beta(1) mRNA in tumor cells was not significantly correlated with the other clinicopathologic parameters investigated or with a worse (disease-free) survival. Expression of the PAI-1 protein in tumor cells was strongly correlated with worse overall and disease-free survival, in addition to well-known prognostic parameters such as lymph node metastasis, depth of tumor infiltration, tumor size and vasoinvasion. In the multivariate analysis, PAI-1 turned out to be a strong independent prognostic factor. In a subgroup of patients without lymph node metastases, PAI-1 was predictive for worse survival and relapse of disease, too. Our results show that the (enhanced) expression of PAI-1 by carcinoma cells is correlated with worse (overall and disease-free) survival of patients with cancer of the uterine cervix. The expression of TGF-beta(1) in itself is not associated with worse survival in these patients. Although simultaneous presence of the 2 factors was observed in all tumors, induction of PAI-1 by TGF-beta(1) could not be demonstrated in our group of cervical carcinomas.

Transforming growth factor-beta plasma dynamics and post-irradiation lung injury in lung cancer patients

PURPOSE

To investigate the relevance of transforming growth factor-beta (TGF-beta) dynamics in plasma for identification of patients at low risk for developing pneumonitis as a complication of thoracic radiotherapy (RT).

PATIENTS AND METHODS

Non-small cell lung cancer patients undergoing conventional RT were included in the prospective study. Concentrations of TGF-beta were measured in the patients' plasma prior to and weekly during 6 weeks of RT. The incidence of symptoms of early post-irradiation lung injury, i.e. symptomatic radiation pneumonitis, was correlated with TGF-beta parameters.

RESULTS

Forty-six patients were included in the study. Eleven patients (24%) developed symptomatic radiation pneumonitis. Absolute TGF-beta plasma levels did not differ between the groups of patients without or with pneumonitis. However, patients who developed pneumonitis tended to show increases in TGF-beta levels in the middle of the RT course relative to their pre-treatment levels while TGF-beta plasma levels of patients who did not develop pneumonitis tended to decrease over the RT treatment. The difference in the relative TGF-beta dynamics between the groups reached marginal significance in the third week of the treatment (P = 0.055) but weakened towards the end of the RT course. The utility of TGF-beta testing was evaluated at each RT week based on the test's ability to yield more accurate estimate of complication probability in an individual patient compared to empirically expected probability in similar group of patients. The ratio of TGF-beta level at week 3/week 0 being <1 showed an ability to improve the prediction of freedom from pneumonitis, yet with a large degree of uncertainty (wide confidence intervals). The accuracy of prediction deteriorated at later time points (weeks 4, 5 and 6) rendering the end-RT ratios without predictive power.

CONCLUSIONS

We observed a trend of plasma TGF-beta concentration to decrease below the pre-treatment value during the RT treatment in patients who did not develop pulmonary complications after the RT treatment. However, this trend was not consistent enough to warrant safe decision-making in clinical setting.

Reduced expression of transforming growth factor-beta receptors is an unfavorable prognostic factor in human esophageal squamous cell carcinoma

Transforming growth factor-beta (TGF-beta) inhibits epithelial cell proliferation. Inactivation of the TGF-beta signaling pathway is thought to play a role in tumorigenesis. Our purpose was to clarify the correlation between TGF-beta receptors or TGF-beta 1 expression and the clinicopathologic characteristics of patients with esophageal squamous cell carcinoma (SCC). Immunohistochemical staining for TGF-beta type I receptor (TGF-beta R-I), TGF-beta R-II and TGF-beta 1 was performed on surgical specimens obtained from 80 patients with esophageal SCC. Preoperative plasma TGF-beta1 levels were measured and correlated with pathologic features and clinical outcomes. Expression of TGF-beta R-I and TGF-beta R-II was reduced in 43 (53.8%) and 23 (28.8%) specimens, respectively. TGF-beta 1 was overexpressed in 29 (36.3%). Reduced expression of TGF-beta R-I and TGF-beta R-II showed a significant association with depth of invasion (p = 0.0015 and p = 0.0012), lymph node metastasis (p = 0.0309 and p = 0.0059) and pathologic stage (p = 0.0103 and p = 0.0401). Overexpression of TGF-beta 1 had a significant association with depth of invasion only (p = 0.0335). Reduced expression of TGF-beta R-I and TGF-beta R-II was correlated with cancer-specific survival (p = 0.0324 and p = 0.0243). The mean preoperative plasma TGF-beta 1 level was 10.5 +/- 0.8 ng/ml in patients with esophageal carcinoma and was significantly higher compared to healthy controls (p < 0.01). We demonstrate that reduced expression of TGF-beta receptors in esophageal SCC appears to be correlated with depth of invasion, lymph node metastasis, pathologic stage and poor prognosis. TGF-beta receptor expression may play a key role in the progression of this cancer.

Polymorphism in codons 10 and 25 of the transforming growth factor-beta 1 (TGF-beta1) gene in patients with invasive squamous cell carcinoma of the uterine cervix

Transforming growth factor-beta 1 (TGF-beta1) has a multifactorial role in the development of cervical cancer. It potently inhibits the growth of epithelial cells that harbour oncogenic human papilloma viruses (HPVs). TGF-beta1 also inhibits the expression of the early viral transforming regions E6 and E7, which appear to be the key oncoproteins. It has been suggested that squamous cell carcinomas are devoid of TGF-beta1, raising the possibility that elevated levels of this growth factor could protect against cervical cancer. It is also recognized that the production and levels of TGF-beta1 are genetically predetermined and individually variable. Two genetic polymorphisms in the DNA encoding the leader sequence of the TGF-beta1 gene have been described and shown to be associated with the production of high or low TGF-beta1 levels in vivo and in vitro. We hypothesized that the inheritance of these polymorphisms could influence the development of invasive cervical cancer. This hypothesis was investigated by studying polymorphism in codons 10 and 25 of the TGF-beta1 gene. We studied 97 patients with invasive cervical cancer and 73 healthy controls and found that the distributions of alleles T (Leu) and/or C (Pro) and alleles G (Arg) and/or C (Pro) in codons 10 and 25, respectively, were similar. There was no significant association between the alleles and the histological degree of cancer differentiation. It appears that the role of this growth factor in cervical oncogenesis is not related to the point mutations that we examined in codons 10 and 25 of the TGF-beta1 gene. We speculate that other factors, including additional polymorphisms of the TGF-beta1 gene, the status of TGF-beta1 receptors, the complex cytokine network, differential responsiveness of cells to the stimuli, and the status of the precancer/cancer genome, may play a role in development of invasive cervical cancer.

The impact of TNF-alpha induction on therapeutic efficacy following high dose spatially fractionated (GRID) radiation

A variety of cytokines especially TNF-alpha and TGF-beta are known to be released in response to high dose radiation of tumors. However, these are not normally measurable in systemic circulation unless high levels of these cytokines are produced by tumor cells. This study was undertaken to see if circulating levels of these cytokines could be measured in the serum of patients treated with high dose spatially fractionated (GRID) radiation and to correlate the finding of these cytokines with clinical response to treatment. Thirty-four patients (31 patients had single treatment site and 3 patients had 2 treatment sites) treated with spatially fractionated (GRID) radiation were entered in this study. Serum samples were collected before treatment and at 24, 48 and 72 hours after GRID radiation. Sandwich enzyme linked immunosorbent assay (ELISA) was performed to estimate the levels of TNF-alpha and activated TGF-beta1 proteins. Seven of 37 patients studied had no TNF-alpha protein before treatment but showed induction of TNF-alpha after GRID radiation. Three patients showed faint basal level of TNF-alpha protein before treatment and these levels were induced after treatment. Three patients showed a basal level of TNF-alpha protein before treatment and these levels decreased after treatment. In 21 cases no TNF-alpha protein was detected before or after treatment at the time points measured. In the case of TGF-beta1 protein, 2 patients showed no TGF-beta1 protein before GRID radiation and an induction of TGF-beta1 protein was observed after treatment. Seven patients showed basal level of TGF-beta1 protein prior to treatment and these levels were induced after treatment. Seventeen patients showed a basal level of TGF-beta1 protein before treatment and these levels decreased after treatment. In 8 cases no TGF-beta1 protein was detected before or after treatment. Complete clinical response (CR) to GRID therapy was seen in 12/37 (32%) treatment sites and partial response (PR) in 18/37 (49%) treatment sites. A strong correlation was observed between clinical CR rate and TNF-alpha induction. The rate of CR was 6/10 (60%) in patients where TNF-alpha was induced as compared to 6/27 (23%) treatment sites in patients where TNF-alpha induction was not seen (p = 0.029). No significant correlation with CR rate and TGF-beta1 induction (44% vs. 28%, p = 0.36) was observed. High dose spatially fractionated (GRID) radiation results in significant induction of TNF-alpha that can be measured in serum of some patients 24 72 hours after radiation. Complete tumor response strongly correlated with the induction of TNF-alpha levels in the serum.

Lymphocyte radiosensitivity is a significant prognostic factor for morbidity in carcinoma of the cervix

PURPOSE

To study the relationship between pretreatment peripheral blood lymphocyte radiosensitivity and morbidity following radiation therapy.

METHODS AND MATERIALS

A prospective study was carried out in which patients with carcinoma of the cervix underwent radiation therapy. Intrinsic radiosensitivity was measured on pretreatment peripheral blood lymphocytes, using a limiting dilution clonogenic assay. Late morbidity was assessed using the Franco-Italian glossary. Results were correlated in an actuarial analysis.

RESULTS

There were no correlations between the measured lymphocyte radiosensitivity (SF2) and colony-forming efficiency, patient age, tumor grade, or disease stage. For 83 patients, lymphocyte SF2 was a significant prognostic factor for the probability of developing both any (p = 0.002) and Grade 3 (p = 0.026) morbidity. In 174 patients, stage showed borderline significance as a prognostic factor for morbidity (p = 0.056). However, the type of treatment (intracavitary alone, intracavitary plus parametrial irradiation, single insertion plus whole-pelvis irradiation) was significantly associated with the probability of developing late complications (p = 0.013). There was a weak significant inverse correlation between lymphocyte SF2 and grade of morbidity (r = -0.34, p = 0.002).

CONCLUSION

These data highlight the importance of normal cell radiosensitivity as a factor determining radiation therapy response. They also show that peripheral blood lymphocyte SF2 is a highly significant prognostic factor for the probability of developing late radiation morbidity, and that carcinoma of the cervix is a good model for testing radiobiologic principles in the clinic.