[Why Strive after Clinical Social Medicine? From Epidemiological Association to Personalized Social Medicine: a Case of Breast Cancer Care]. / Klinische Sozialmedizin - Warum? Von der epidemiologischen Assoziation zur personalisierten Sozialmedizin am Beispiel der Versorgung bei Mammakarzinom.

Advances in biomedicine, especially molecular biology and genetics, gave rise to the concept of personalized medicine targeting the patient's individual characteristics and needs to ensure the best possible therapy and healthcare. This concept, however, can be successfully implemented only if due consideration is given to (psycho-)social factors, as is shown for instance by considerably reduced post-therapy survival rates among cancer patients in regions with lower socioeconomic status, How breast cancer patients, for instance, find their way back to daily life and work after initial treatment at a breast center is substantially determined by multiple factors going beyond pure medical care. These factors critically affect health status and therapy outcomes, but are missing in current research agenda. A profound expertise in social medicine is required to respond in ways tailored to the individual's healthcare needs that go beyond just medical therapy. This expertise comprises, in particular, knowledge of inequality of access to healthcare due to varying health competence that in turn, results in inequality of health outcome and care. Competence in social medicine both in the clinic and outpatient care can help to individually target negative factors that originate from the social environment as well as from deficits in communication and coordination in the healthcare system and have an effect on the health status of patients..This, however, requires institutionalization of (clinical) social medicine and in particular, better opportunities for advanced training in social medicine in clinical departments and outpatient units.

Patients who die during palliative radiotherapy. Status survey.

BACKGROUND AND PURPOSE: Palliative radiotherapy (RT) is routinely used in end of life care of patients with advanced malignancies; however, unnecessarily burdensome treatment shortly before death should be avoided. There is little knowledge on incidence and causes of intercurrent deaths during palliative RT. PATIENTS AND METHODS: In this study death events among inpatients receiving palliative RT between January 2009 and December 2011 at this department were retrospectively analyzed. Among epidemiological factors, treatment schedule and chronology, latency and duration of treatment in relation to the actual survival were identified. RESULTS: In this study 52 patients died during or shortly after palliative RT. Symptomatic bone metastases and brain metastases represented the most common RT indications. The general health status was poor with a median Karnofsky performance score of 50 %, RT was realized with a median single dose of 2.5 Gy to a median total dose of 30.5 Gy and was stopped prematurely in 73 % of patients. On average 53 % of the remaining lifetime was occupied by latency to starting RT. Once RT was begun the treatment duration required a median 64 % of the still remaining lifetime. CONCLUSION: The majority of patients who died had explicitly adverse pre-existing factors and rarely completed RT as scheduled. Latency to RT and RT duration occupied more than half of the remaining lifetime.

[Plea for a strengthening of clinical social medicine]. / Plädoyer für eine Stärkung der klinischen Sozialmedizin.

Social medicine is concerned--in the midst of a constantly changing society--with the social and economic conditions that influence health, disease and medical care. A comprehensive medical care therefore requires medical doctors who, beyond the biomedical issues, realize diseases in the context of the social needs of the individual person and systematically include these in their prevention, treatment and rehabilitation concepts.The system of social security, particularly the health care system, depends on medical doctors' expertise in helping patients for the appropriate use of services from the system of social security. According to the German professional education regulations for doctors the additional specialization in "social medicine" also includes the competence for "assessment of the nature and extent of health disorders and their classification in the framework of social security systems". This judgment is one part of the tasks of the Medical Services belonging to the various branches of the social security system. It is also provided in practice by medical doctors with competence in social medicine working in acute care facilities.

Multiple malignancies in a single patient : a glimpse into 30 years of interdisciplinary oncology.

We report on an 83-year-old woman who suffered from seven manifestations of at least five different nonmetastasizing malignancies during a period spanning more than three decades. Although suspected, an inherited genetic tumor syndrome could not be detected. This patient history exemplifies the development of interdisciplinary oncology and specifies the success but also the risks of intensified locoregional treatments. In particular, radiation oncologists routinely have to perform a risk-benefit analysis, rendering their work both challenging and fascinating.

Effect of concurrent chemotherapy and hyperthermia on outcome of preoperative radiotherapy of high-risk soft tissue sarcomas.

BACKGROUND AND PURPOSE: As treatment results for high-risk soft tissue sarcoma are still disappointing, treatment intensification is warranted. We performed a retrospective analysis of multimodal preoperative treatment to evaluate the additional effect of concurrent chemotherapy and/or locoregional hyperthermia in comparison to radiotherapy alone. PATIENTS AND METHODS: Between 1999 and 2011, 28 patients were treated with neoadjuvant radiotherapy to a median 45 Gy for high-risk soft tissue sarcoma. All tumors were deep-seated and grade 2 or 3, 86% (n = 24) larger than 5 cm. Multimodal treatment (n = 12) consisted of ifosfamide (n = 7), locoregional hyperthermia (n = 3), or both modalities (n = 2) concurrent to radiotherapy. RESULTS: Prognostic factors (grade, size, histology, location) were balanced in the groups with and without concurrent multimodal treatment. There was a significant improvement of disease-specific survival (100% vs. 70% at 3 years, p = 0.03) with multimodal treatment. Distant metastases-free survival was influenced, but was not statistically significant. Local control and disease-free survival did not differ in the two groups. CONCLUSION: Our data suggest that multimodal treatment with ifosfamide and/or locoregional hyperthermia in combination with neoadjuvant radiotherapy might improve outcome in high-risk soft tissue sarcomas.

Feasibility of 6-month maintenance cetuximab after adjuvant concurrent chemoradiation plus cetuximab in squamous cell carcinoma of the head and neck.

BACKGROUND: Close resection margins < 5 mm (CM) or extra capsular extent at the lymph nodes (ECE) impair the prognosis of patients with squamous cell cancer of the head and neck (SCCHN) scheduled for adjuvant radiochemotherapy. We conducted a multicenter phase II study to investigate toxicity and efficacy of additional cetuximab administered concomitantly and as maintenance for the duration of 6 months following adjuvant radiochemotherapy., Ppreliminary results on feasibility and acute toxicity on skin and mucosa are presented in this article. METHODS: Patients with SCCHN following CM resection or with ECE were eligible for the study. In all, 61.6 Gy (1.8/2.0/2.2 Gy, days 1-36) were administered using an integrated boost intensity-modulated radiotherapy (IMRT) technique. Cisplatin (20 mg/m(2), days 1-5 and days 29-33) and 5-fluorouracil (5-FU) as continuous infusion (600 mg/m(2), days 1-5 + days 29-33) were given concurrently. Cetuximab was started 7 days prior to radiochemotherapy at 400 mg/m(2) followed by weekly doses of 250 mg/m(2). Maintenance cetuximab began after radiochemotherapy at 500 mg/m(2) every 2 weeks for 6 months. RESULTS: Of the 55 patients (46 male, 9 female, mean age 55.6, range 29-70 years) who finished radiochemotherapy, 50 were evaluable for acute toxicity concerning grade III/IV toxicities of skin and mucosa. Grade 3-4 (CTC 3.0) mucositis, radiation dermatitis, and skin reactions outside the radiation portals were documented for 46, 28, and 14 % of patients, respectively. One toxic death occurred (peritonitis at day 57). Cetuximab was terminated in 5 patients due to allergic reactions after the first application. In addition, 22 % of patients discontinued cetuximab within the last 2 weeks or at the end of radiochemotherapy. Of patients embarking on maintenance treatment, 80 % were still on cetuximab at 3 months and 63 % at 5 months. Concurrent and maintenance treatment with cetuximab could be administered as scheduled in 48 % of patients. CONCLUSION: Adjuvant radiochemotherapy with concomitant and maintenance cetuximab is feasible and acute toxicities are within the expected range. Compliance within the first 3-5 months is moderate.

Cerebral metastases in extrapulmonary cell carcinoma. Implications for the use of prophylactic cranial irradiation.

BACKGROUND AND PURPOSE: Extrapulmonary small cell carcinoma (EPSCC) is a rare disease. Standard treatment is performed in analogy to small cell lung cancer; however, due to the differences in rates of cerebral metastases (CM), prophylactic cranial irradiation (PCI) is not routinely used. Therefore, we evaluated the characteristics of all patients developing brain metastases in a population of EPSCC patients and calculated a number needed to treat (NNT) for the prevention of cerebral metastases by PCI. PATIENTS, METHODS, AND RESULTS: Of 51 patients treated at our institution from 1999-2011 for EPSCC, 11 presented with CM, 5 at initial diagnosis, 6 in the course of their disease. Median overall survival after primary diagnosis of EPSCC was 12 months. Overall survival after diagnosis of CM was significantly in favor of primarily cerebrally metastasized patients with 9 compared to 2 months for secondary CM (p = 0.04), median survival for all patients being 4 months. The NNT calculation was based on the 6 patients with secondary brain metastases in our series and a relative risk reduction of 60% observed in the studies of PCI for small cell lung cancer (SCLC), resulting in an NNT of 13. CONCLUSION: Although the frequency of brain metastases in EPSCC was lower than in SCLC, the NNT of 13 for the prevention of CM, as well as the poor median survival after diagnosis of secondary brain metastases of 2 months might be a reason to discuss and evaluate PCI for EPSCC patients responding to initial therapy.

Postoperative versus definitive chemoradiation in early-stage anal cancer. Results of a matched-pair analysis.

BACKGROUND AND PURPOSE: The goal of the present study was to comparatively assess the results of definitive chemoradiation (CRT) with or without previous macroscopically complete resection in patients with early-stage node-negative (T1-2 N0) anal carcinoma. PATIENTS AND METHODS: A total of 20 patients with T1-2 N0 anal carcinoma who received radiotherapy (RT) with or without chemotherapy following incidental R0/1 tumor resection (S/CRT group) were selected. These were matched to 20 comparable patients who underwent definitive chemoradiation without previous surgery (CRT group). Major objectives of this analysis were treatment outcomes in terms of locoregional tumor control (LRC), overall survival (OS), colostomy-free survival, and toxicity. RESULTS: Patients treated postoperatively received significantly lower RT doses (median 54.0 Gy vs. 59.7 Gy; p < 0.001) and less frequently concomitant chemotherapy than those treated definitely. The 5-year LRC and 5-year OS rates were 97.5% and 90.0%, respectively, without significant differences between the S/CRT and the CRT groups. The distribution of acute and late toxicities was comparable, and the 5-year colostomy-free survival was 95% in both groups. CONCLUSION: This matched-pair comparison of incidental R0/1 resection plus dose-reduced CRT with standard definitive CRT of early-stage anal cancer shows similar treatment results. Thus, dose-reduced RT with or without chemotherapy may be considered in R0/1 resected patients with T1-2 N0 anal carcinoma.

Limited disease of extra-pulmonary small cell carcinoma. Impact of local treatment and nodal status, role of cranial irradiation.

PURPOSE: As extra-pulmonary small cell carcinoma (EPSCC) is a rare entity of tumors, the available treatment recommendations are mainly based on retrospective analyses and deduction from treatment of small cell lung cancer. The aim of this study was to provide a detailed analysis concerning prognostic factors and treatment modalities. PATIENTS AND METHODS: A total of 20 patients with limited disease (LD) of EPSCC treated at our institution from 1999­2009 were retrospectively analyzed. Data were gathered from chart review. Localization, lymph node involvement, as well as local and systemic treatment were documented and their impact on pattern of failure and survival times statistically evaluated. RESULTS: With a median follow-up of 21 months, the estimated median overall- and disease-free survival were 59 and 25 months, respectively. Local control was excellent with 100% at 2 years. Nodal involvement was observed in 74% (n = 14/19) of evaluable patients. However, outcome was not altered by this parameter. Local treatment consisted of surgery in 10 cases, radiotherapy in 7 cases, and a combination of both in 3 cases. Only 3 patients (15%) developed hematogenous central nervous system metastases, while none of the patients received prophylactic cranial irradiation. CONCLUSION: Nodal involvement did not worsen prognosis. Local control was excellent irrespective of local treatment modality and the leading cause of failure was distant metastasis. Therefore, systemic treatment should not be omitted. Prophylactic cranial irradiation might be dispensable but discussed for head and neck malignancies.

Outcome after whole brain radiotherapy alone in intracranial leptomeningeal carcinomatosis from solid tumors.

BACKGROUND: The purpose of the present study was to investigate outcome after whole brain radiotherapy (WBRT) alone as a palliative treatment without concomitant chemotherapy for intracranial leptomeningeal carcinomatosis (LMC). PATIENTS AND METHODS: Overall survival and treatment response were retrospectively analyzed in 27 consecutive patients with LMC from breast and lung cancer. All patients had evidence of intracranial manifestations of LMC. Seven potential prognostic factors were evaluated. RESULTS: Median overall survival (OS) for the entire group was 8.1 weeks. OS rates after 6 and 12 months were 26% and 15%, respectively. Improvement of neurological deficits was observed in 3 patients. In 3 of 4 patients with follow-up MRI studies, a decreased size of contrast-enhanced lesions was observed. Prognostic factors for improved OS on univariate analysis were absence of cranial nerve dysfunction, Karnofsky Performance Score (KPS) > 60%, and time interval > 35 months between the initial diagnosis of malignant disease and development of LMC. On multivariate analysis, absence of cranial nerve dysfunction remained the only significant prognosticator for OS (median 3.7 vs. 19.4 weeks, p < 0.001). CONCLUSION: WBRT alone is an effective palliative treatment for patients unfit/unsuitable for chemotherapy and low performance status suffering from intracranial LMC. However, prognostic factors should be considered in order to identify patients who are likely to benefit from WBRT.

Are there biologic differences between male and female breast cancer explaining inferior outcome of men despite equal stage and treatment?!

BACKGROUND: Reasons for inferior outcome of male compared to female breast cancer are still under debate. Therefore, we retrospectively analyzed male breast cancer cases to figure out possible treatment- and gender-related differences. PATIENTS AND METHODS: A total of 40 men (median age 62 years) were curatively treated with mastectomy and postoperative radiotherapy from 1982-2007. They presented predominantly in stages II and IIIb. Postoperative radiotherapy was applied with doses of 1.8-2.5 Gy to a median of 50 Gy including regional lymphatics in 22 patients. Adjuvant systemic treatment consisted of chemotherapy (22.5%) and antihormonal treatment (55%). For reasons of comparison, we estimated outcome of a virtual female matched cohort for no/equal to men/optimal adjuvant treatment with the Adjuvant!Online(®) 8.0 algorithm. RESULTS: After a median follow-up of 47 months, the estimated 5-year local control rate was 97%, disease-free and distant metastasis-free survival rates reached 79% and 82%, respectively. With update of survival data by tumor registry, mean overall survival reached 120 months with 5- and 10-year overall survival rates of 66% and 43%, respectively. Predominant prognostic factor was T-stage for overall survival (T1/2 vs. T4: > 80% vs. 30%). The generated virtual matched cohorts of women with equal characteristics reached superior 10-year-overall survival for no/equal to men/optimal adjuvant treatment with 55/59/68%. CONCLUSION: Compared to historical and virtual matched cohorts of women, male breast cancer patients had inferior outcome despite of equal stage and treatment which indicates that biological differences (of tumor or population) may contribute to worse prognosis.

Adjuvant radiochemotherapy in patients with locally advanced high-risk cervical cancer.

BACKGROUND AND PURPOSE: The aim of this retrospective study was to analyze the outcome of patients with locally advanced cervical carcinoma treated by adjuvant radiochemotherapy and to determine risk factors for local and distant relapse. Furthermore, acute and late effects of treatment were recorded. PATIENTS AND METHODS: A total of 72 patients with FIGO stages I-III cervical carcinoma were treated by radical hysterectomy, pelvic lymphadenectomy, and postoperative radiochemotherapy. Only patients with positive pelvic lymph nodes, parametrial involvement, positive margins, or tumor bulk were eligible. Patients were irradiated with a standard pelvic field (50.4 Gy in 28 fractions). The majority of patients received platinum-based chemotherapy. RESULTS: After a median follow-up of 37 months, estimated 1-, 2-, and 4-year disease-free survival (DFS) and overall survival (OS) rates were 89%, 80%, 68% and 95%, 88%, 76%, respectively. Nine of the 72 patients had pelvic recurrences including only 1 isolated local failure; 23 of the 72 patients presented with distant relapse. The majority of relapses occurred within the first 3 years after adjuvant treatment. The number of positive pelvic lymph nodes (> 1) was the strongest prognostic factor for DFS. Treatment was well tolerated with transient acute hematologic (~30%) and gastrointestinal (~30%) grade 3 toxicity. Small bowel obstruction (~6%) was the only important late sequelae. CONCLUSION: Adjuvant radiochemotherapy in patients with advanced cervical cancer and several risk factors is highly effective to prevent local relapse. Future efforts to improve outcome should be placed on improvement of systemic control especially in subgroups with high-risk features for distant relapse. Combined treatment was well tolerated with moderate acute and late toxicity.

Toxicity and outcome of pelvic IMRT for node-positive prostate cancer.

BACKGROUND AND PURPOSE: This study reports on the treatment techniques, toxicity, and outcome of pelvic intensity-modulated radiotherapy (IMRT) for lymph node-positive prostate cancer (LNPPC, T1-4, c/pN1 cM0). PATIENTS AND METHODS: Pelvic IMRT to 45-50.4 Gy was applied in 39 cases either after previous surgery of involved lymph nodes (n = 18) or with a radiation boost to suspicious nodes (n = 21) with doses of 60-70 Gy, usually combined with androgen deprivation (n = 37). The prostate and seminal vesicles received 70-74 Gy. In cases of previous prostatectomy, prostatic fossa and remnants of seminal vesicles were given 66-70 Gy. Treatment-related acute and late toxicity was graded according to the RTOG criteria. RESULTS: Acute radiation-related toxicity higher than grade 2 occurred in 2 patients (with the need for urinary catheter/subileus related to adhesions after surgery). Late toxicity was mild (grade 1-2) after a median follow-up of 70 months. Over 50% of the patients reported no late morbidity (grade 0). PSA control and cancer-specific survival reached 67% and 97% at over 5 years. CONCLUSION: Pelvic IMRT after the removal of affected nodes or with a radiation boost to clinically positive nodes led to an acceptable late toxicity (no grade 3/4 events), thus justifying further evaluation of this approach in a larger cohort.

[A new working shift model for anesthesiologists: an analysis 3 years after implementation]. / Neues Dienstzeitenmodell für Ärzte in der Anästhesie : Eine Analyse 3 Jahre nach Implementierung.

OBJECTIVE: The aim of this study was to assess the efficacy, appropriateness and cost-effectiveness of a new working shift model for anesthesiologists complying with the European working time directive (EWTD) at the University Hospital of Tübingen (UKT), Germany 3 years after implementation BACKGROUND: Applying the standards of the EWTD is challenging for university hospitals as doctors must comply with the challenge of combining patient care, research and teaching. So far there have been no data available for German university hospitals on how these requirements can be met. As the department of anesthesiology is also a service-providing department it is essential not to increase staffing costs with a new shift model. METHODS: In 2007 a new working shift model for the department of anesthesiology was designed and introduced in 2008. Shift planning and documentation of working hours were implemented electronically. The calculated number of doctors to run this model was 87.6 full time equivalents (FTE). For 2009 and 2010 the compliance with the EWTD parameters was checked for 1) average weekly working time limit (AWWTL) and 2) compliance to the maximum daily working time limit of 10 h (10 h DWTL). Furthermore, staffing costs for doctors in 2010 were compared to 2007. To check for the time spent in patient care the period of anesthetic attendance (PAA) was chosen, i.e. the total time of patient contact by anesthesiology staff. Data were analyzed descriptively for AWWTL and for 10 h DWTL. FTE, staff costs and PAA were evaluated by one-way ANOVA. RESULTS: The new shift model allowed 84.4 % of all doctors to comply with the individual AWWT limits of 54 h and 48 h in 2009 (81/96) and 76.0 % in 2010 (79/104). In 2009 61.5 % of anesthesiologists voted for opt-out (59/96) and 53.8 % did so in 2010 (56/104). The 10 h DWTL was respected by 84.0 % in 2009 and by 85.9 % in 2010. The mean number of anesthesiologists rose significantly from 78.4 FTE in 2007 to 82.5 FTE in 2009 and 84.6 FTE in 2010 (p < 0.001 for 2010 vs. 2007, p = 0.004 for 2009 vs. 2007 and was not significant for 2010 vs. 2009). Staff costs per FTE increased from 7,524.79 /month to 7,800.66 /month and 7,966.11 /month in 2007, 2009 and 2010, respectively with the differences being non-significant. The PAA increased significantly from a mean of 6,124 h/month in 2007 to 6,581 h/month in 2009 and 6,872 h/month in 2010 (p < 0.001 for 2010 vs. 2007, whereas 2009 vs. 2007 and 2010 vs. 2009 were not significant). Thus, labour costs increased from 96.59 /h PAA in 2007 to 98.53 /h in both 2009 and 2010, the differences being not significant. CONCLUSIONS: The newly designed shift model allowed a fair compliance with the EWTD in respect to AWTL and 10 h DWTL, although the calculated number of doctors to run the shift model could not be met in 2009 and 2010. Violations of the 10 h DWT limits were stable in 2009 and 2010; however the number of doctors exceeding the AWWT limits appeared to increase. The compliance with opt-out decreased from 2009 to 2010 and a high proportion of AWWTL violations resulted from the group of non-opt-out voters. The staff costs per hour PAA after implementation of the new shift model did not differ significantly from the year before although staffing costs increased by 7.2 % between 2007 and 2010. Costs increased by 162,454 /year for all PAA hours in 2010. Further evaluation of staff satisfaction with the new shift models is needed and already under way.

Determinants of survival in patients with brain metastases from cutaneous melanoma.

BACKGROUND: This retrospective study aimed to identify prognostic factors in patients with brain metastases from cutaneous melanoma. METHODS: In all, 265 patients under regular screening according to valid national surveillance guidelines were included in the study. Kaplan-Meier analyses were performed to estimate and to compare overall survival. Cox modeling was used to identify independent determinants of the overall survival, which were used in explorative classification and regression tree analysis to define meaningful prognostic groups. RESULTS: In total, 55.5% of our patients presented with two or less brain metastases, 82.6% had concurrent extracranial metastasis and 64% were asymptomatic and diagnosed during surveillance scans. In all, 36.7% were candidates for local treatment (neurosurgery or stereotactic radiosurgery (SRS)). The median overall survival of the entire collective was 5.0 months (95% confidence interval: 4.3-5.7). Favourable independent prognostic factors were: normal pre-treatment level of serum lactate dehydrogenase (P<0.001), administered therapy (neurosurgery or SRS vs other, P=0.002), number of brain metastases (single vs multiple, P=0.032) and presence of bone metastasis (false vs true, P=0.044). Three prognostic groups with significantly different overall survival were identified. Candidates for local treatment (group I) had the longer median survival (9 months). Remaining patients could be further classified in two groups on the basis of serum lactate dehydrogenase. CONCLUSION: Applied treatment and serum lactate dehydrogenase levels were independent predictors of survival of patients with brain metastases from cutaneous melanoma. Patients receiving local therapy have overall survival comparable with general stage IV melanoma patients.

Salvage chemotherapy for metastatic breast cancer: results of a phase II study with bendamustine.

BACKGROUND: Bendamustine, a bifunctional alkylating agent with anticipated purin-like properties is active in metastatic breast cancer (MBC) patients. This multicenter phase II trial defines the toxicity and activity of bendamustine in heavily pretreated patients. PATIENTS AND METHODS: Fifty-one patients were included. Patients had a median number of 2 prior chemotherapeutic regimens for MBC (range 0-7) consisting of anthracyclines and taxanes: 26 patients (51%); anthracyclines: nine patients (17.6%); taxanes: seven patients (13.7%); others: five patients (9.8%). Bendamustine was administered four weekly at a dose of 120 mg/m(2) on days 1 and 2. RESULTS: Fifty patients were assessable. Of total, 200 courses were administered. We observed no complete response (CR); 10 patients [20%; 95% confidence interval (CI): 10.0% to 33.7%] achieved a partial response (PR), 14 patients (28%) remained stable for at least 6 months resulting in a clinical benefit rate (CR + PR + stable disease) of 48% (95% CI: 33.7%to 52.6%). Median time to progression was 3.4 months (range 1-51.1). The median duration of remission was 6.6 months (range 1.8-48.7). The treatment was well tolerated with mainly hematologic toxic effects. CONCLUSION: Single-agent bendamustine is an active treatment in patients with MBC independent of the previous treatment. The low toxicity profile favors its use as a single agent.

Photoimmunotherapy of human ovarian carcinoma cells ex vivo.

Photodynamic therapy is a relatively new and potentially selective experimental approach to the treatment of malignant neoplasms. Its inherent dual selectivity is reinforced by the use of photosensitizer-monoclonal antibody conjugates. The goal of this study was to evaluate the phototoxicity and selectivity of an immunoconjugate (IC) synthesized from a chlorin derivative chlorin e6-monoethylenediamine monoamide (CMA) as the photosensitizer and an anti-ovarian carcinoma monoclonal antibody OC125. Binding efficiency and specificity of the IC were determined by enzyme-linked immunosorbent assay, and specific covalent linkage of the monoclonal antibody to the photosensitizer was demonstrated by fluorescence and electrophoresis. Phototoxicity was tested against ascites or pleural fluid cells from 15 patients with ovarian and nonovarian cancers. Tumor cells from the fluid were treated with the IC at 3 microM equivalent CMA concentration and irradiated at 654 nm (lambda max CMA in IC) at 25 J/cm2 from an argon ion-pumped dye laser. Phototoxic efficacy was assayed by [3H]thymidine incorporation. Ovarian cancer cells exhibited high cytotoxicity with [3H]thymidine incorporation of 2.4 +/- 2.2%, while nonovarian cancer cells under identical conditions exhibited none to reduced cytotoxicity with [3H]thymidine incorporation of 70 +/- 54%. Using a Wilcoxon test, there was a statistically significant difference between these two groups (P less than 0.001). Dose-response curves revealed reciprocity in photosensitizer concentration and fluence. These results demonstrate that photoimmunoconjugates retain significant antigen binding specificity and affinity, are effective in the selective photochemical eradication of target cells, and merit further evaluation as photochemotherapeutic agents.

Rapid growth of human cancer cells in a mouse model with fibrin clot subrenal capsule assay.

Rapid in vivo growth of cultured human cancer or leukemia cells was achieved by implantation into the subrenal capsule of mice. A solid structure, necessary for accurate implantation and measurement of tumor growth in this model, was provided by stepwise addition of fibrinogen and thrombin to the tumor cells, leading to rapid enzymatic formation of a solid tumor-fibrin matrix. Human leukemia and epithelial cancers increased in volume between 6- and 40-fold when measured 6-10 days after implantation into normal or immunosuppressed mice. Immunosuppression of host CD-1 mice was achieved by cyclosporine given daily after tumor implantation, cyclophosphamide given preimplantation combined with cyclosporine, or whole-body irradiation given preimplantation. Confirming the validity of tumor measurements, tumor histology in the immunosuppressed mice revealed cell proliferation, invasion, and neovascularization. Similarly, no artifactual measurement of tumor growth was observed by nonviable cancer cells, implanted after in vitro exposure to a known cytotoxic concentration of thiotepa. This model provides an economical, short-term technique for the in vivo study of human tumor growth, for the evaluation of new cancer therapies, and for in vitro - in vivo drug activity correlations in specific types of human cancer or leukemia cell lines.

Intraperitoneal photodynamic therapy of human epithelial ovarian carcinomatosis in a xenograft murine model.

The objective of this investigation was to determine the efficacy of i.p. photodynamic therapy (PDT) against solid, multifocal ovarian carcinoma using a newly described NIH:OVCAR-5 induced murine model. PDT was initiated when diffuse microscopic disease and small multifocal tumor nodules were present, similar to the extent of residual carcinoma that may persist clinically after laparotomy and tumor debulking. The photosensitizer, benzoporphyrin derivative monoacid ring A (BPD-MA), was administered in a dose of 0.25 mg/kg body weight i.p. 90 min prior to light exposure. An argon-pumped dye laser was used to deliver low intensity light (20 J) i.p. through a cylindrically diffusing fiberoptic tip. Treatment regimens consisted of a series of three to five treatments at 3-7 day intervals, with the extent of macroscopic disease or death from disease being the evaluable outcome parameters for tumoricidal and survival studies, respectively. The mean tumor burden at necropsy for treated animals was 0.034 +/- 0.014 g compared to 0.379 +/- 0.065 g in untreated controls (P<0.001). Survival studies were initiated in two groups at day 7 and day 14 following cell inoculation. The first group received either three or five treatments at 5-day intervals, and both had a significant increase in median survival compared to untreated controls (57 and 53 days, respectively, compared to 43 days, P<0.05). The second group was treated every 7 days until death and also had a significant survival advantage over controls (57 days compared to 47 days, P<0.05). These studies suggest that benzoporphyrin derivative mono acid ring A-mediated PDT is a feasible, well-tolerated, experimental treatment approach that elicits a tumoricidal response against diffuse, solid i.p. disease in tumor-bearing mice, with concomitant prolongation of survival and needs careful optimization.