Characterization of tumor-associated B-cell subsets in patients with colorectal cancer

Purpose:

A precise understanding of the mechanisms by which human immune cell subsets affect tumor biology will be critical for successful treatment of cancer using immunotherapeutic approaches. Recent evidence suggests that B cells can both promote and inhibit the development and progression of tumors. The aim of this study was to characterize the composition of the B-cell infiltrates in colorectal cancers (CRC) in order to gain further insight into the role of B cells in CRC.

Experimental Design:

In this study we characterized B-cell subsets in primary tumors (n=38), metastases (n=6) and blood (n=46) of 51 patients with a diagnosis of CRC and blood of 10 healthy controls. B-cell subsets were analyzed by flow cytometry or immunohistochemistry.

Results:

Peripheral blood of CRC patients contained a higher percentage of memory B cells than that of age-matched healthy controls. Furthermore, the percentage of B cells within tumors was higher than that in the peripheral blood of CRC patients while metastases were typically devoid of tumor-infiltrating B cells. Tumor-associated B cells were enriched for activated and terminally differentiated B cells. Relevant proportions of regulatory B cells could only be detected in advanced cancer and metastases.

Conclusion:

B cells constitute a significant proportion of the immune infiltrate in CRC. The B-cell infiltrate of primary CRC is characterized by an accumulation of terminally differentiated memory B cells or plasma cells suggestive of a specific immune response against the tumor. However advanced tumors and metastases are also infiltrated by a considerable number of regulatory B cells.

[Localization of primary small cell carcinoma with liver metastasis: a rare combination of colonic adenocarcinoma and undifferentiated small cell carcinoma]

Neuroendocrine or small cell cancer (SCC) is a rare tumor, accounting for less than 1% of all colorectal cancers. There is a high rate of metastasis in SCC. Overlying adenomas are commonly present in colorectal SCC. We present a case of a 67-year-old female patient with liver metastasis of SCC. Initially, the primary tumor was not found and the patient underwent chemotherapy. Ten months later, an adenocarcinoma of the right hemicolon was endoscopically diagnosed due to anal hemorrhage and right hemicolectomy was performed. Microscopic examination revealed that the adenocarcinoma was combined with an undifferentiated carcinomatous component. Immunocytochemistry was positive for synaptophysin and chromogranin. In our case a very rare combination of colonic adenocarcinoma and SCC within an overlying adenoma was found.

[Fatal outcome factors of intestinal infarct of primary vascular origin]

Despite diagnostic and therapeutic advances, mesenteric vascular occlusion with intestinal infarction is often fatal. Parameters determining the high mortality are seldom discussed in the literature. By univariate statistical analysis we correlated the therapeutic outcome of our patients to 20 parameters. Between 1 January 1984 and 30 April 1996 we treated 22 men and 18 women with acute bowel ischemia of vascular origin. All patients underwent laparotomy, 40% (n = 16) due to the diagnosis of mesenteric infarction. In 15% (n = 6) the laparotomy was only exploratory; in 34 cases (85%) bowel resection was carried out. Mortality for all patients was 55% (n = 22). Univariate analysis of the 20 parameters showed that the therapeutic outcome was significantly correlated to a pre-existing diabetes, the course of hospitalization, and the high ASA class. There was no correlation to the length of resected bowel. Most parameters that determine the mortality of bowel infarction are pre-existing and cannot be influenced, but survival can be achieved in some patients if radical and aggressive resection is carried out at the side of almost complete small bowel infarction and followed by an elective second-look operation. Even short-bowel syndrome can be treated. Patients can return to a near normal lifestyle with an acceptable quality of life with the aid of parenteral nutrition at home.

[Extramedullary plasmocytoma of the bronchial system]

We present a case of primary plasmocytoma of the left upper bronchus. Occlusion led to atelectasis of the left upper lobe and subsequent poststenotic pneumonia. Therapy consisted of local excision of the bronchus and postoperative radio-therapy. This type of lung-conserving therapy in a case of primary plasmocytoma has not been described before.

[Long-term results of abdominal surgery interventions. Different evaluation from the viewpoint of the patient, the surgeon and the public health office]

The patient, the surgeon and the public health officer (Versorgungsamt) assess the long-term results of abdominal operations differently. We tried to objectivize these different assessments. The clinical data were collected retrospectively. Data on postoperative subjective state and degree of handicap were obtained in a written patient survey (March 1995). Two groups with benign diseases and one group with malignant disease were examined: 59 patients who had undergone sigmoidectomy for diverticulitis (30 female and 29 male patients, median age: 61.5 years), 347 patients subjected to proximal gastric vagotomy for duodenal ulcers (72 female and 275 male patients, median age: 46 years) and 158 patients who had undergone gastrectomy for gastric carcinoma (56 patients female, 102 patients male, median age: 61 years). The public health officer, classed 35.6% of the patients who had undergone sigmoidectomy and 34.6% of the patients who underwent vagotomy as officially handicapped with a stated grade of disablement, 77.2% of the patients with gastrectomy were officially classed as handicapped. When other diseases were taken into account in addition, 27.1% of the patients who had undergone sigmoidectomy, 27.4% of those who had undergone vagotomy and 75.9% of the patients with gastrectomy had received passes officially identifying them as severely handicapped persons. In the vast majority of cases, the combination of several different ailments had resulted in recognition of a graded handicap and severely disabled person's pass, skeletal, cardiac and circulatory ailments being the most frequent. In spite of this, the evaluation of post-operative course by our patients, the surgeon and the public health officer (as reflected in the official state classification) in terms of the degree of handicap clearly differed.

[Ileocecal tuberculosis as rare differential diagnosis of lower abdominal tumor]

Tuberculosis is extremely rare in Germany today. Diagnosis of extrapulmonary tuberculosis has proved to be particularly difficult and a correct diagnosis can take months. The danger of fatality is high. In the case of a 29 year old male paraplegic patient suffering from enteral tuberculosis, diagnosis was possible only after several weeks of onward observation, extreme physical degeneration and finally, a laparotomy.