Oat cell carcinoma of esophagus: a report of six British patients with a review of the literature.

This paper presents 6 British patients with a diagnosis of oat cell carcinoma of the esophagus. Sixty-six patients have previously been reported in the literature, the majority (30) being British. Approximately two-thirds of these tumors have been reported as pure oat cell carcinoma of the esophagus. Four other histological patterns have been described: oat cell carcinoma with squamous carcinoma in situ; oat cell carcinoma with squamous carcinoma; oat cell carcinoma with adenocarcinoma; and oat cell carcinoma with carcinoid differentiation. A preponderance of males has also been noted, although this series shows a 2:1 female:male ratio. The tumor arises most commonly in the mid or lower esophagus. The cell of origin of these tumors in considered to be the Kulchitsky or APUD cell of neuroectodermal derivation. They may show neurosecretory granules on electron microscopy. Polypeptides have been identified within the tumor cells. One previous report describes a patient with primary oat cell carcinoma of the esophagus and hypercalcemia. A patient with the syndrome of inappropriate anti-diuretic hormone secretion is described in this paper. Survival is poor following radiotherapy, with a median survival of 3 months in this series. On reviewing the records of the Radiation Oncology Unit in Edinburgh, no patient with oat cell carcinoma of the esophagus was reported before 1972. This suggests that awareness of this tumor is increasing and, although rare, its incidence is greater than previously reported.