The use of carcinoembryonic antigen and peptide hormones to stage and monitor patients with lung cancer

Abnormal Serum Hormone Levels in Lung Cancer

Serum levels of chorionic gonadotropin (HCG), testosterone, luteinizing hormone (LH) and prolactin were evaluated with the radioimmunoassay in 59 patients with lung cancer, 10 patients with benign lung disease, and 37 normal controls. HCG was present in 6.8% of the lung cancer patients but in none of the subjects of the other two groups. Prolactin and LH levels were significantly higher than normal in lung cancer patients (respectively p < 0.001 and p < 0.01) as well as in patients with benign lung disease (p < 0.01 for both the hormones). Testosterone levels were significantly lower than normal in patients with lung cancer (p < 0.05) but not in those with benign lung disease. When the patients were analyzed according to histologic type and clinical stage of disease, significantly lower than normal values of testosterone were found in patients with small cell carcinoma or squamous cell carcinoma. In the squamous cell carcinoma group, the patients with lymph node metastases had significantly lower testosterone levels than those without lymph node metastases. From these results, we may hypothesize that the raised levels of prolactin and LH are related to a pulmonary pathology, not necessarily neoplastic, whereas the low levels of testosterone are related to the presence of the tumor.

CEA Determination in the Follow-Up of Extracolorectal Neoplasms

CEA was initially described as a tumor and organ specific colorectal antigen, but later found by more sensitive methods in other tumors (stomach, pancreas, lung, breast) and in minor amounts in inflammatory, normal adult and fetal organs of the gastrointestinal tract. The main clinical application of CEA concerns its pretherapeutic and serial determination as circulating antigen in serum and other body fluids by means of CEA-specific, commercially available test kits. By clinical studies a significant correlation has been proven between the pretherapeutic serum CEA level and tumor stages and prognosis. Moreover, serial CEA level changes have been shown a valuable monitor following operation or during radio/chemotherapy anticipating and reflecting the clinical course of disease. In combination with newly established tumor markers, the main clinical indication for CEA determination in addition to colorectal cancer concerns monitoring of patients with stomach (+ CA 72-4), lung (+ NSE/SCC) and breast cancer (+ CA 15-3/MCA).

An atypical endocrine tumor of the lung responsive to radiation therapy and 5-fluorouracil-streptozotocin

A case is reported of a patient who presented with a peripheral left upper-lobe lung mass, a thyroid nodule, and multiple enlarged cervical and supraclavicular lymph nodes. Fine-needle aspiration cytology of the lung lesion, the thyroid nodule, and several of the lymph nodes was interpreted as small cell cancer of the lung (SCCL). The patient was treated with Cytoxan (cyclophosphamide), Adriamycin (doxorubicin), and vincristine (CAV), alternating with VP-16 + cisplatin. When progressive disease was documented after three cycles of chemotherapy, an involved cervical lymph node was biopsied. By light microscopy (LM) the tumor appeared to be a poorly differentiated adenocarcinoma, but by transmission electron microscopy (TEM) it was found to have both neuroendocrine and glandular features. Biochemical analysis of the biopsy specimen revealed immunoreactive bombesin, and on immunoperoxidase staining many tumor cells contained neuron-specific enolase. The tumor was therefore classified as an atypical endocrine tumor of the lung (AETL), a recently described morphologic variant for which no therapy has yet been established. The patient was treated with radiation therapy (RT) followed by chemotherapy including 5-fluorouracil (5-FU) (500 mg/m2 IV, d 1-5) and streptozotocin (STZ) (500 mg/m2 IV, d 1-5) every 5-6 weeks, with objective evidence of tumor regression following each modality. This report illustrates the importance of ultrastructural study in the characterization of lung cancer, and indicates the need for the further evaluation of RT and 5FU + STZ in the treatment of neuroendocrine tumors of the lung.

Ability of CEA blood levels to reflect tumour burden: a study in a human xenograft model

The relationship of serum carcinoembryonic antigen (CEA) levels to tumour size and antigen content was studied in artificially immune-deprived mice bearing human colonic, breast and lung tumour xenografts. Size was measured as in vivo volume and tumour weight at post-mortem. A multiple implant technique combined with early harvest was used to minimize centrilobular tumour necrosis. CEA was extracted from resected tumours with perchloric acid. A radioimmunoassay using chemical precipitation was used to estimate CEA in blood samples. A correlation was found between CEA blood levels and tumour size in half the tumour lines, in contrast to a recent report (Lewis & Keep, 1981). The CEA content was found to be constant for one tumour line but not another. The possibility that central necrosis in xenograft tumours may account for the discrepancies is discussed. There may be serious limitations for the use of xenograft tumour models for studying the biology of CEA.