What is the best method for minimizing bias in a national trial comparing two arms therapy regimens?

Related MCQs

• A 58-year-old woman with a 60-pack-year smoking history is evaluated because of hemoptysis and weight loss. Chest radiograph and CT scan show a right perihilar mass with mediastinal adenopathy. The results of CT scans of the abdomen, bone scan, and MRI of the head are otherwise negative. Examination of a specimen by bronchoscopic biopsy confirms small-cell lung cancer, and the findings suggest limited-stage disease. After the patient completes mediastinal radiation therapy and four cycles of cisplatin and etoposide, repeat CT scans indicate that her disease is in complete remission. What is the best recommendation concerning further therapy?
• A 50-year-old menstruating woman has a 1 .5-cm moderately differentiated breast cancer. The lesion is completely excised, and the margins of the excision are negative. Axillary node sampling shows that she has three positive nodes. The tumor is negative for estrogen and progesterone receptors and is highly positive for HER2. She is otherwise healthy. Her mother had breast cancer at 62 years and was treated by mastectomy; she is alive and healthy at the age of 80 years. The patients sister had breast cancer at 54 years and was treated by breast conservation therapy; 4 years later she died of a recurrence of breast cancer. The patient has seen two different surgeons with opposing viewpoints regarding the best treatment, and she has been reading extensively on the Internet and has become confused about her options. Which of the following represents the best treatment for this patient?
• A 43-year-old man is evaluated because of crushing substernal chest pain that developed during a pickup basketball game with colleagues at work. He was treated 15 years ago for stage IIB massive mediastinal Hodgkin‟s disease. Treatment included doxorubicin, bleomycin, vinbiastine, and dacarbazine (ABVD) followed by mantle-field radiation therapy to a total dose of 4400 cGy. He has had no recurrence of his Hodgkin‟s disease. He takes thyroid medication because he developed hypothyroidism 2 years after completing his therapy for Hodgkins disease. What is the most likely diagnosis?
• A 68-year-old woman is evaluated because of a lump on her chest wall. Seventeen years ago she developed stage I ductal adenocarcinoma (estrogen receptor-positive) of the left breast; her disease was managed with lumpectomy, breast radiation therapy, and 5 years of tamoxifen therapy. The lump she now has is separate from the breast, subcutaneous in location, fixed to the underlying 4th rib, and nontender. The mass is excised and found to be a fibrosarcoma. What is the relationship of this fibroscarcoma to her original cancer and its treatment?
• A 47-year-old woman is recovering from surgery for stage III ovarian cancer (spread to the peritoneal cavity but without parenchymal liver involvement). Not all of the visible cancer could be resected; the largest residual tumor was 3 cm in diameter. Her performance status is excellent. She is interested in pursuing aggressive therapy and wishes to be treated as soon as possible in her local community. The proposed systemic therapy will involve cisplatin or carboplatin and paclitaxel. What further treatment is appropriate for this patient?
• A 76-year-old man was diagnosed with prostate cancer 8 years ago. At that time he had a serum prostate-specific antigen (PSA) level of 12 ng/mL, a Gleason score of 6, and a clinical stage of T2b (organ-confined on digital rectal examination but involving both lobes of the prostate gland). He was treated with external-beam radiation therapy, and his PSA level dropped to a low of 1.4 ng/mL. Four years later, his PSA level began to rise and now is 14.1 ng/mL. A recent bone scan and CT scans revealed no metastatic disease. His urologist has suggested initiating a course of leuprolide. Which of the following is a potential side effect of leuprolide that the patient should be informed about before commencing therapy?
• Which of the following results is associated with concurrent chemoradiation therapy versus radiation therapy alone for patients with locally advanced laryngeal cancer, based on the RTOG 91-11 study?
• Which of the following side effects is NOT associated with long-term hormonal therapy combined with radiation therapy for prostate cancer?
• Which of the following types of cancer was associated with a statistically significant improvement in survival for patients who had one to three solitary brain metastases and received whole brain radiation therapy with the addition of stereotactic radiosurgery, according to results of the RTOG 9508 phase III trial?
• According to Intergroup Trial 0116, adjuvant chemotherapy and radiation therapy after gastrectomy were more likely than gastrectomy alone to: