SCLC

Two main methods have been used to measure the charge carrier mobility in electroluminescent polymers time of flight (TOF) carrier transit time measurements and analysis of the current-voltage (1-V) characteristics of single carrier devices in the space charge-limited current (SCLC) regime. A summary of the results for the hole mobility of PPV and PPV-related polymers is given in Table 11-1 [24, 27-32]. For... 

One result of the field-dependent mobility is that the space charge-limited current (SCLC, the maximum current that can How in the bulk of the sample) does no longer follow a simple V2H scaling [132] on the voltage Land sample thickness L. Muigatroyd [133] was able to show that, for a mobility as in Eq. (13.4), the monopolar SCLC current could be well approximated by ... 

Clinical trials showed therapeutic efficacy in a broad spectrum of tumors these include SCLC, testicular tumors, sarcomas, breast cancer, renal cell cancer, pancreatic tumors and lymphomas. Ifosfamide is less myelosuppressive than cyclophosphamide but is more toxic to the bladder. Therefore it is recommended that ifosfamide is coadministered with the thiol compound mesna to avoid hemorrhagic cystitis and to reduce the risk of developing bladder cancer. Other side effects include neurotoxicity and myelosuppression. 

There are four major histologic types of lung cancer that are divided into two classes based on response to treatment and prognosis small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). However, it is important to note that certain other rare malignancies can be seen as well as mixed-type carcinomas. The four major types of lung cancer are outlined in Table 87-1. 

The most commonly used system of staging SCLC was developed originally by the Veterans Administration Lung Cancer Study Group. This system categorizes SCLC into two classifications limited and extensive disease.16... 

Small cell lung cancer typically presents as extensive disease (approximately 60% to 70% of new cases) and progresses very quickly. Small cell carcinomas are very responsive to chemotherapy and radiation. Radiotherapy became the standard in 1969, when a randomized trial showed that it offered the potential for cure, whereas surgery did not.20 For the vast majority of patients, chemotherapy with or without radiotherapy is the treatment of choice. Even after a complete response to therapy, the cancer usually recurs within 6 to 8 months, and survival time following recurrence is typically short ( 4 months). This yields a typical survival rate of 14 to 20 months for limited disease and 8 to 13 months for extensive disease.33 Table 87-6 illustrates the general treatment path of SCLC. 

The treatment of recurrent disease depends on the time to recurrence. If the time to recurrence is less than 6 months, second-line therapy should be considered if the patient has an acceptable performance status (see Patient Care and Monitoring ). The most widely accepted second-line therapies in SCLC are topotecan alone or CAV [cyclophosphamide, doxorubicin (Adriamycin), vincristine]. Relapses occurring more than 6 months after treatment warrant a repeat of the initial regimen. Poor performance status patients (3—4) typically are treated with palliative care therapies. 

Testicular cancer SCLC NSCLC ANLL KS HD NHL BMT preparative chemotherapy gastric cancer... 

Vincristine (VCR, Oncovin) ALL HD NHL multiple myeloma breast cancer SCLC, KS brain tumors soft tissue sarcomas osteosarcomas neuroblastoma Wilms tumor... 

Radiation therapy is the treatment of choice for chemotherapy-resistant tumors such as non-small cell lung cancer (NSCLC) or in chemotherapy-refractory patients with SVCS. Between 70% and 90% of patients will experience relief of symptoms. Radiation therapy also may be combined with chemotherapy for chemotherapy-sensitive tumors such as SCLC and lymphoma. In the rare emergency situations of airway obstruction or elevated intracranial pressure, empirical radiotherapy prior to tissue diagnosis should be used. In most patients, symptoms resolve within 1 to 3 weeks. 

Cytotoxic chemotherapy is the treatment of choice for chemotherapy-sensitive tumors such as SCLC and lymphoma. As indicated earlier, chemotherapy also may be combined with radiotherapy, especially in patients with lymphoma who have bulky mediastinal lymphadenopathy. 

Lung cancer is a solid tumor originating from bronchial epithelial cells. This chapter distinguishes between non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) because they have different natural histories and responses to therapy. 

The major cell types are SCLC (-15% of all lung cancers), adenocarcinoma (-50%), squamous cell carcinoma (less than 30%), and large cell carcinoma. The last three types are grouped together and referred to as NSCLC. 

A two-stage classification is widely used for SCLC. Limited disease is confined to one hemithorax and the regional lymph nodes. All other disease is classified as extensive. 

Surgery is almost never indicated because SCLC disseminates early in the... 

SCLC is very radiosensitive. Radiotherapy has been combined with chemotherapy to treat limited disease SCLC. This combined-modality therapy prevents local tumor recurrences but only modestly improves survival over chemotherapy alone. 

Radiotherapy is utilized to prevent and treat brain metastases, a frequent occurrence with SCLC. Prophylactic cranial irradiation is used in selected patients to reduce the risk of brain metastases. Neurologic and intellectual impairment are associated with prophylactic cranial irradiation, although other factors may also contribute. 

Chemotherapy with concurrent radiation is recommended for limited-and extensive-disease SCLC. Single-agent chemotherapy is inferior to doublet chemotherapy. 

Recurrent SCLC is usually less sensitive to chemotherapy. If recurrence is more than 6 months after induction chemotherapy, the original regimen can be repeated. If recurrence occurs in less than 6 months but >3 months, treatment options include a taxane, gemcitabine, topotecan, irinotecan, CAV (cyclophosphamide, doxorubicin, and vincristine), and vinorelbine. 

Patients with SCLC that recurs within 3 months of first-line chemotherapy are considered refractory to chemotherapy and unlikely to respond to a second-line regimen. 

Efficacy of induction therapy for SCLC should be determined after two to three cycles of chemotherapy. If there is no response or progressive disease, therapy can be discontinued or changed to a non-cross-resistant regimen. If responsive to chemotherapy, the induction regimen should be administered for four to six cycles. 

Topotecan is the second camptothecin derivative it is itself an active drug, and received FDA approval as second line therapy in metastatic ovarian cancer (1996) and in SCLC (1998) [13], In addition, representatives of a second generation of topi inhibitors, the homocamptothecins, are now being developed for chemotherapy, e.g., BN-80915 and BN-809271 [14]. 

UCN-01 201 (staurosporine analog) (190) Alkaloidal antibiotic KRX-0601 (UCN-01, KW-2401) (190) Oncology Inhibition of CDKs Phase n (melanoma, TCL, SCLC) Keryx (Kyowa Hakko/NCl) 902-905... 

CCK receptors SCLC, pancreatic cancers, neuroblastomas, meningiomas, medullary thyroid carcinomas... 

Opioid receptors SCLC, neuroblastomas, breast tumors, thymomas... 

Bremnes RM, Sundstrom S, Aasebo U, Vilsvik J. Paclitaxel in combination with cisplatin, etoposide and thoracic radiotherapy for limited stage small cell lung cancer (SCLC) a phase II study (abstract 1826). ProAmSoc Clin Oncol 1998 17 475a. 

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