Tumors of the esophagus.

This collective review includes all available case reports of smooth muscle (stromal) tumors of the esophagus in the world literature. Compiling this review, we endeavored to examine cumulative and recently collected data of both benign and malignant esophageal smooth muscle tumors found in the literature spanning the period from 1875 to 1996, which totaled 1679 leiomyomas (LMs) and 165 leiomyosarcomas (LMSs). The peak age of occurrence of benign smooth muscle tumors in the esophagus was found to be between the ages of 30 and 59, whereas the highest frequency of malignant tumors was seen later in life, during the decade from age 60 to 69. The most common location of both LMs and LMSs was the lower third of the esophagus. Their patterns of growth differed; LMs were more likely to grow intramurally, and LMSs were predominantly intraluminal. Most patients with LMs presented with dysphagia and pain or discomfort; patients with LMSs additionally commonly complained of weight loss. As with smooth muscle tumors of other areas of the gastrointestinal tract, the duration of symptoms averaged 1 month to 1 year, and malignant tumors grew to larger sizes than benign neoplasms. Approximately one-third of LMSs had metastasized at diagnosis, and there was a 5-year survival rate of approximately 20%.

Tumors of the appendix and colon.

This collective review includes all available case reports of smooth muscle (stromal) tumors of the appendix and large intestine in the world literature. When compiling this review, we endeavored to examine cumulative as well as recently collected data on both benign and malignant smooth muscle tumors spanning the period 1875 to 1996. In total, there were reports of 331 leiomyomas (LMs) and 263 leiomyosarcomas (LMSs). The peak age of incidence of LM was 30 to 39 years, and the peak age of incidence of LMSs was 50 to 59 years. The female/male ratio was slightly higher for LM, and the male/female ratio was higher for LMS. The descending colon and sigmoid colon were the most common sites of both benign and malignant smooth muscle tumors. The growth of LMs most often occurred extraluminally, whereas LMSs tended to grow within the lumen of the colon. With both tumor types pain was the most frequent presenting complaint, followed less commonly by complaints of a palpable mass or gastrointestinal bleeding. LMSs tended to be larger at diagnosis than LMs, though the duration of symptoms for both types of tumor was most often reported to be between 1 month and 1 year. Finally, LMSs were found to metastasize mo

Tumors of the stomach.

This collective review includes all available case reports of smooth muscle (stromal) tumors of the stomach in the world literature from 1762 to 1996. It updates our previous review from 1767 to 1959. Overall, we identified 2189 patients with leiomyoma (LM) and 1594 with leiomyosarcoma (LMS). The peak age of incidence of LM was 50 to 59 years, while LMS was most frequently seen between ages 60 and 69. Women were more likely to develop LM, and men more commonly presented with malignant smooth muscle tumors of the stomach. Concerning the patterns of growth, LMs were more likely to grow intraluminally (endogastric), whereas LMSs were predominantly exogastric. The most common site of LMs was on the anterior or posterior wall of the body of the stomach; LMSs were most likely found along the greater curve. The presenting symptoms of both types of smooth muscle tumors were similar; in decreasing order of frequency they were bleeding, pain, palpable mass, and weight loss. Interestingly, there was no correlation between the size of the tumor and signs or symptoms of bleeding, pain, weight loss, or ulceration, although patients with LMSs were more likely to report weight loss than patients with benign tumors. For LMS, there seemed to be no correlation between tumor size or location and rate of metastasis, although the tumors that grew in a dumbbell shape (i.e., both intraluminally and extraluminally) had a higher frequency of metastasis than other growth patterns. Overall, the rate of metastasis at diagnosis was 35.4%, with the liver, spleen, and regional lymph nodes the most common sites.

Tumors of the small intestine.

This collective review includes all available case reports and series of smooth muscle (stromal) tumors of the small intestine in the world literature from 1881 to 1996. We identified 1074 patients with leiomyoma (LM) and 1689 with leiomyosarcoma (LMS). Our purpose was to update our previous review, which encompassed case reports and series from 1881 to 1959, which included 350 LMs and 257 LMSs. The peak incidence of smooth muscle tumors in the small intestine in both male and female patients was between the ages of 50 and 59. Most commonly, the presenting complaint was gastrointestinal bleeding. Computed tomography was found to detect LM and LMS most successfully and had the additional advantage of locating metastatic disease. The jejunum contained the highest numbers of smooth muscle tumors, followed by the ileum and then the duodenum, with malignant lesions in all locations typically attaining larger diameters than benign tumors. The overall rate of metastatic spread of LMS ranged from 24% to 50%, with the liver being most commonly involved. Unlike other sarcomas, both hematogenous and lymphatic spread were common. The 5-year survival of 705 patients with LMS from 22 series was 27. 8%. For both benign and malignant smooth muscle tumors of the small intestine, surgery remains the treatment of choice, with little efficacy reported for irradiation, chemotherapy, or both.

Tumors of the rectum and anal canal.

This collective review includes all available case reports of smooth muscle (stromal) tumors of the rectum and anal canal in the world literature. When compiling this review we endeavored to present cumulative and recently collected data of both benign and malignant smooth muscle tumors found in the literature spanning the period from 1881 to 1996, which totaled 432 leiomyomas (LMs) and 480 leiomyosarcomas (LMSs) of the anus and rectum. The peak age of frequency for LMs was 40 to 59 years and 50 to 69 years for LMSs; men were slightly more likely to develop both benign and malignant anorectal smooth muscle tumors than women. Intraluminal growth of both LMs and LMSs was more frequently seen than extraluminal or intramural patterns, and tumors were more likely to be found in the rectum than in the anus. Patients with LMs presented most commonly with gastrointestinal (GI) bleeding, a palpable mass, or anorectal pain. As with smooth muscle tumors in other areas of the alimentary tract, symptoms likely persisted for less than 1 year prior to diagnosis. As was also the case for these neoplasms in other GI locations, LMSs tended to be larger than LMs. Approximately 20% of LMSs reported from 1881 to 1996 had metastasized at diagnoses. The local recurrence rate for resectable tumors was more than 80%, exceeding the propensity of LMSs in other areas of the GI tract to recur.

End-point parameter adjustment on a small desk-top programmable calculator for logit-log analysis of radioimmunoassay data.

We describe an improved method of logit-log curve fitting, by adjusting end-point parameters in radioimmunoassay studies, for use with a small desk-top programmable calculator. Straight logit-log analyses are often deficient because of their high sensitivity to small errors in the end-point parametes B0 and NSB (the actual measured activity in the tubes). The literature suggests techniques for adjusting these end-point parameters, but they require too much computing time and programming space to be used with a desk-top programmable calculator. The extension to the logit-log model presented here is easily handled by the programmable calculator and provides a good estimate of the change required in B0 and NSB to obtain a better fit. The program requires 1.5 min to run on our desk-top programmable calculator, and has resulted in improved data analysis for all of the 11 types of radioimmunoassay studied.