Comparison of disease progression and mortality of connective tissue disease-related interstitial lung disease and idiopathic interstitial pneumonia.

OBJECTIVE: To compare disease progression and mortality between idiopathic interstitial pneumonia (IIP) and interstitial lung disease (ILD) due to connective tissue diseases (CTD) including scleroderma, rheumatoid arthritis, systemic lupus, polymyositis, dermatomyositis, Sjögren's syndrome, and mixed CTD. METHODS: A case-control study of patients with CTD-ILD (n = 46) and IIP controls (n = 51), seen at the University of Michigan between July 1,1998 and June 30,1999 and followed until March 30, 2002, was conducted. Survival analysis and Cox regression were performed to estimate survival, accounting for demographic and clinical parameters, including pulmonary function tests and high resolution computed tomography (HRCT) diagnosis and scoring. RESULTS: Median followup time was 4.4 person-years. Five-year survival in the IIP group was 51.9% (95% confidence interval [95% CI] 30.8-69.4) versus 43.4% (95% CI 21.1-63.9) in the CTD-ILD group. There were no significant differences among HRCT diagnostic categories between IIP and CTD-ILD. A fibrotic score > or = 2 was associated with decreased survival among the entire group. Age at diagnosis and most recent forced vital capacity were significant predictors of mortality when adjusted for IIP versus CTD-ILD diagnosis, sex, and interstitial score. CONCLUSION: Contrary to expectation, CTD-ILD compared with IIP appears to be associated with a worse prognosis when adjusted for age. A higher fibrotic score is suggestive of decreased survival.

Responsiveness of human prostate carcinoma bone tumors to interleukin-2 therapy in a mouse xenograft tumor model.

We have tested an immunotherapy approach for the treatment of metastatic prostate carcinoma using a bone tumor model. Human PC-3 prostate carcinoma tumor cells were heterotransplanted into the femur cavity of athymic Balb/c nude mice. Tumor cells replaced marrow cells in the bone cavity, invaded adjacent bone and muscle tissues, and formed a palpable tumor at the hip joint. PC-3/IF cell lines, generated from bone tumors by serial in vivo passages, grew with faster kinetics in the femur and metastasized to inguinal lymph nodes. Established tumors were treated with systemic interleukin-2 (IL-2) injections. IL-2 significantly inhibited the formation of palpable tumors and prolonged mouse survival at nontoxic low doses. Histologically IL-2 caused vascular damage and infiltration of polymorphonuclear cells and lymphocytes in the tumor as well as necrotic areas with apoptotic cells. These findings suggest destruction of tumor cells by systemic IL-2 therapy and IL-2 responsiveness of prostate carcinoma bone tumors.

Prospects of immunotherapy for the treatment of prostate carcinoma--a review.

The treatment of prostate carcinoma is dependent on the stage of the disease. Patients who present with clinically localized cancer or locally advanced tumors can be potentially cured by radical prostatectomy, radiation, and hormonal therapy. However, disease progression can occur in 30-50% of patients diagnosed with clinically localized cancer. The bone is the predominant site of metastases. Metastatic prostate cancer is first treated by androgen blockade but within a few months becomes hormone refractory. Hormone refractory metastatic prostate cancer is not responsive to conventional treatments, and patients have an expected survival of less than a year. It is essential to develop new approaches for the treatment of hormone refractory metastatic disease. Immunotherapy, based on enhancement of the host immune response against the tumor, has been used as an alternative therapy for the treatment of metastatic cancers refractory to conventional therapy in particular for melanoma and renal cell carcinoma. In this review, we will summarize various immunotherapeutic approaches developed over the last 18 years, and we will address the potential of immunotherapy for the treatment of metastatic prostate carcinoma by reviewing preclinical studies and initial clinical trials performed in this field.

Systemic interleukin 2 therapy for human prostate tumors in a nude mouse model.

Once the regional lymph nodes become involved in prostate carcinoma, 85% of patients develop distant metastases within 5 years, and metastatic disease is difficult to treat. We have investigated the effect of systemic interleukin 2 (IL-2) treatment on metastatic prostate carcinoma using a xenograft tumor model. Cells from a PC-3/IF cell line, produced by intrafemoral injection of human PC-3 prostate carcinoma cells, were injected in the prostate of Balb/c nude mice. Prostate tumors and para-aortic lymph nodes were resected, and tumor cells were recultured and passaged in the prostate in vivo to produce new cell lines. On day 6 following prostatic injection of these cell lines, mice were treated with i.p. injections of IL-2 at 25,000-50,000 units/ day for 5 consecutive days. The effect of IL-2 on tumor progression was assessed, and histological studies were performed on prostate tumor and lymph node sections. The tumor cell lines generated by serial prostate injection were tumorigenic and metastasized to regional para-aortic lymph nodes. Tumors of 0.4 cm were obtained by day 16 and grew to 1-1.5 cm by day 40 with metastasis to para-aortic lymph nodes. Following two to three weekly courses of 5 days of 25,000-40,000 units/day of IL-2, the growth of prostate tumors was inhibited by 94%. Higher doses of 50,000 units/ day were toxic. Histologically, prostate sections showed vascular damage manifested by multifocal hemorrhages and an influx of lymphocytes and polymorphonuclear cells into disintegrating tumors and areas of necrosis containing numerous apoptotic cells. In contrast to control mice, para-aortic lymph nodes were not enlarged in responding mice. These findings suggest that systemic IL-2 therapy can induce an antitumor response in prostate tumors and control their growth and metastasis.