Incidental Axillary Lymphadenopathy Found on Radiation Planning Computed Tomography

PURPOSE

The aim of this study was to evaluate the rate of axillary node-positive disease in patients with early breast cancer who had a suspicious axillary lymph node on radiation planning computed tomography (CT).

METHODS AND MATERIALS

A retrospective review was conducted of the medical records of all patients with breast cancer who were referred for axillary ultrasound from the radiation unit to the breast imaging unit at the Meirav Breast Center, Sheba Medical Center, from 2012 to 2022. Ethics approval was obtained. Only the records of patients who were referred due to an abnormal axillary lymph node seen on radiation planning CT were further evaluated.

RESULTS

During the study period, a total of 21 patients were referred to the breast imaging unit for evaluation of suspicious nodes seen on radiation planning CT. Of these, 3 cases were excluded. A total of 15 out of the 18 (83%) patients included had an abnormal lymph node in the ultrasound, and an ultrasound-guided biopsy was recommended (BI-RADS 4). Of these, 3 (out of 15, 20%) had a positive biopsy for tumor cells from the axillary lymph node. Two were cases after primary systemic therapy without complete pathologic response. Thickening of the lymph node cortex and complete loss of the central fatty hilum were associated with pathologic lymph node.

CONCLUSION

Sonar had limited ability to differentiate reactive nodes from involved nodes. The presence of lymph nodes with loss of cortical-hilum differentiation on ultrasound together with clinical features are parameters that can help guide the need of further biopsy. Histopathology evaluation is important to make the diagnosis of residual axillary disease. Future studies and guidelines are needed to improve the diagnostic abilities and reduce the number of patients who are undergoing biopsy for noninvolved nodes.

Characterization of patients with a diagnosis of breast cancer and melanoma: genetic susceptibility or increased surveillance?

BACKGROUND

Breast cancer diagnosis had been linked to an increased risk of melanoma in several reports. The aim of the current study was to assess the role of genetics, increased surveillance, and radiation treatment in patients with a dual diagnosis of breast cancer and melanoma (DBM).

MATERIALS AND METHODS

All patients treated at Sheba Medical Center between 2007 and 2021 with DBM were included in the cohort. Data on family history, genetic tests, characteristics, and treatment of both cancers were collected. The proportion of patients with a pathogenic variant (PV) in BRCA1 and BRCA2 genes was compared to a control group of patients with breast cancer. The proportion of patients presenting with in-situ disease was compared to the national registry data.

RESULTS

The cohort included 222 DBM patients of whom 114 had documentation of genetic testing. Twenty patients tested positive for PVs of which 13 (11%) were in BRCA genes. This was comparable to the proportion in patients with a diagnosis of breast cancer (736; 19%). The proportion of melanoma diagnosed at stage 0 was comparable to the national proportion ( N  = 40; 30% vs. 28%, respectively). In comparison to the national registry, a larger proportion of breast cancers were ductal carcinoma in situ or lobular carcinoma in situ [10% in the registry vs. 19% (22) in the cohort; P  < 0.003].

CONCLUSIONS

In patients with DBM we did not find an increased proportion of PVs in BRCA genes. Our findings suggest that the increased standardized incidence ratio of the dual diagnosis may be partially explained by increased surveillance and detection of earlier-stage cancers.

Global Forum of Cancer Surgeons: Cancer Surgery During the COVID-19 Pandemic: Impact and Lessons Learned

Background

The purpose of this article is to summarize the opinions of the surgical oncology leaders from the Global Forum of Cancer Surgeons (GFCS) about the global impact of COVID-19 pandemic on cancer surgery.

Methods

A panel session (virtual) was held at the annual Society of Surgical Oncology 2021 International Conference on Surgical Cancer Care to address the impact of COVID-19 on cancer surgery globally. Following the virtual meeting, a questionnaire was sent to all the leaders to gather additional opinions. The input obtained from all the leaders was collated and analyzed to understand how cancer surgeons from across the world adapted in real-time to the impact of COVID-19 pandemic.

Results

The surgical oncology leaders noted that the COVID-19 pandemic led to severe disruptions in surgical cancer care across all domains of clinical care, education, and research. Several new changes/protocols associated with increased costs were implemented to deliver safe care. Leaders also noted that preexisting disparities in care were exacerbated, and the pandemic had a detrimental effect on well-being and financial status.

Conclusions

The COVID-19 pandemic has led to severe disruptions in surgical cancer care globally. Leaders of the GFCS opined that new strategies need to be implemented to prepare for any future catastrophic events based on the lessons learned from the current events. The GFCS will embark on developing such a roadmap to ensure that surgical cancer care is preserved in the future regardless of any catastrophic global events.

[INTRAOPERATIVE RADIOTHERAPY FOR EARLY BREAST CANCER - THE SHEBA EXPERIENCE AND EARLY OUTCOMES]

AIMS

This study presents our experience with Intra-Operative Electron Radio-Therapy (IOeRT) using a mobile linear accelerator at the Sheba Medical Center.

BACKGROUND

Intraoperative radiotherapy is an alternative approach of partial breast irradiation for patients with early breast cancer and low risk for local recurrence who are undergoing breast conservation surgery.

METHODS

Patients were selected by a multidisciplinary team according to ASTRO\GEC-ESTRO guidelines for partial breast irradiation. IOeRT was administered using SIT LIAC HWL®.

RESULTS

A total of 28 patients were referred for breast conservation surgery and IOeRT between 8/2019 and 10/2020; 27/28 received IOeRT. In one patient, radiation was aborted due to anaphylactic shock in response to patent blue dye injected for sentinel node identification. Larger than usual seroma were reported on the first post-operative visit in all patients, and regressed spontaneously in 3-6 months. Infected seroma developed post-operatively in 5 patients, requiring surgical drainage in 2 patients. Final pathology matched the preoperative biopsy. There were no cases of pathology upstaging requiring additional adjuvant irradiation or chemotherapy. The patient who did not receive IOeRT was treated with adjuvant external radiotherapy.

CONCLUSIONS

IOeRT is a safe alternative to partial breast irradiation, with a slight increase of postoperative infection rate.

Impact of "critical lesions" on outcomes following cytoreductive surgery and hyperthermic intra-peritoneal chemotherapy

BACKGROUND

Peritoneal Cancer Index (PCI) and complete cytoreduction are the best outcome predictors following cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Lesions in critical areas, regardless of PCI, complicate surgery and impact oncological outcomes. We prospectively defined "Critical lesions" (CL) as penetrating the hepatic hilum, diaphragm at hepatic outflow, major blood vessels, pancreas, or urinary tract.

METHODS

Retrospective analysis of a prospective database of 352 CRS + HIPEC patients from 2015 to 2019. Excluded patients with aborted/redo operation (n = 112), or incomplete data (n = 19). Patients categorized by CL status and compared: operative time, estimated blood loss (EBL), PCI, transfusions, hospital stay, post-operative complications and mortality, overall survival (OS) and disease-free survival (DFS).

RESULTS

Included 221 patients (78 CL; 143 no-CL). No difference in patients' characteristics: age, BMI, gender or co-morbidities noted. Operative time longer (5.3 h vs 4.3 h, p < 0.01), EBL higher (769 ml vs 405 ml, p < 0.01), transfusions higher (1.9 vs 0.7 Units, p < 0.001) and PCI higher (15.5 vs 9.5, p < 0.01) in CL. No difference in major complications. Postoperative complications, CL, OR-time and transfusions were predictive of OS in univariate analysis, while only complications remained on multivariate analysis. Median follow up of 21.4 months, 3-year DFS/OS was 22% vs 30% (p < 0.037) and 73% vs 87% (p < 0.014) in CL and non-CL, respectively. Despite CL complete resection, 17/38 patients (44.7%) that recurred had recurrence at previous CL site.

CONCLUSIONS

Critical lesions complicate surgery and may be associated with poor oncological outcomes with high local recurrence rate, despite no significant difference in complications. Utilizing adjuvant or intra-operative radiation may be beneficial.

Post-mastectomy surveillance of BRCA1/BRCA2 mutation carriers: Outcomes from a specialized clinic for high-risk breast cancer patients

Female BRCA1/BRCA2 mutation carriers may elect bilateral risk-reducing mastectomy. There is a paucity of data on yield of imaging surveillance after risk-reducing mastectomy. This retrospective study focused on female BRCA1/BRCA2 mutation carriers who underwent bilateral mastectomy either as primary preventative, or as secondary preventative, after breast cancer diagnosis. All participants underwent breast imaging at 6- to 12-month intervals after mastectomy. Data on subsequent breast cancer diagnosis and timing were collected and compared between the groups. Overall, 184 female mutation carriers (134 BRCA1, 45 BRCA2, 5 both BRCA genes) underwent bilateral mastectomy after initial breast cancer diagnosis, between April 1, 2009 and August 31, 2018. During a mean follow-up of 6.2 ± 4.2 years, 13 (7.06%) were diagnosed with breast cancer; 12 ipsilateral (range: 0.4-28.8 years) and 1 contralateral breast cancer, 15.9 years after surgery. On the contrary, among asymptomatic BRCA1 (n = 40) and BRCA2 (n = 13) mutation carriers who underwent primary risk-reducing mastectomy (mean age at surgery 39.5 ± 8.4 years); none has developed breast cancer after a mean follow-up of 5.4 ± 3.4 years. BRCA1/BRCA2 mutation carriers with prior disease who underwent risk-reducing mastectomy after breast cancer diagnosis are still prone for developing ipsi or contralateral breast cancer, and therefore may benefit from continues clinical and imaging surveillance, unlike BRCA1/BRCA2 mutation carriers who undergo primary preventative bilateral mastectomy.

Time trends in uptake rates of risk-reducing mastectomy in Israeli asymptomatic BRCA1 and BRCA2 mutation carriers

BACKGROUND

The rate of risk-reducing bilateral mastectomy (RRBM) among cancer-free Israeli female BRCA1/BRCA2 mutation carriers was reportedly 13% in 2010. Current RRBM rates in Israel and factors seemingly associated with opting for RRBM were reevaluated.

METHODS

Israeli female cancer-free BRCA1/BRCA2 mutation carriers, who were followed at the high-risk clinic at Sheba Medical Center between January 2011 and April 2020 were eligible. Univariate Cox regression and log-rank test were used to study the crude association between potential predictors and performance of RRBM.

RESULTS

Overall, 427 cancer-free BRCA1 (n = 218) or BRCA2 (n = 209) mutation carriers were included. Median age at genotyping was 33.6 years (interquartile range 26.8-41.8 years), median follow-up 4.4 years (range 0.1-7.6 years). Overall, 41/427 (9.6%) participants underwent RRBM, all of them within 5 years of genotyping. Being married (HR-2.57, p = 0.017) and having a first degree relative with breast cancer (BC) (HR-2.19, p = 0.017) were positively associated with RRBM, whereas any previous benign breast biopsy was negatively associated (HR-0.48, p = 0.029) with performing RRBM.

CONCLUSIONS

RRBM is still infrequently elected by Israeli BRCA1/BRCA2 mutation carriers, with married women with one relative with BC who have not undergone previous breast biopsy more likely to opt for RRBM.

Abstract P2-12-07: Local recurrence of breast cancer: Salvage lumpectomy as a safe option for local treatment

Introduction: The best local management for breast cancer recurrence following conservative treatment for breast cancer (BC) continues to be an open question. In this study, we compared patients' outcome after salvage lumpectomy vs. patients who underwent mastectomy for ipsilateral breast tumor recurrence (IBTR).

Materials and methods: Between 1987 and 2014 we identified 121 patients with pT0-2, N0-3, M0 BC who had breast conserving surgery and radiation as their primary treatment, and subsequently had IBTR (unifocal). 47 patients underwent salvage lumpectomy (SL) and 74 salvage mastectomy (SM) as the local treatment for their 1st recurrence.

Results:

Median follow-up was 14 years (2-30) from first BC diagnosis. All consecutive identified patients, 121, were included in the study. At 1st recurrence, 47 patients (39%) chose to undergo SL for their IBTR, and 74 patients (61%) opted for SM.

The mean age at 1st diagnosis of BC for SL group and SM, was 52 and 47 years, respectively (p=0.006). With similar T in both groups, most patients had T1 (43%), and T2 (34%) at first diagnosis (p=0.722). The women who opted later for SM had more ALND surgery (58% vs. 33%, p=0.023) and received more neoadjuvant chemotherapy (20% vs. 4%, p=0.022) at their first BC diagnosis.

The median DFI at 1st recurrence for SL and SM group was 12 and 7 years, respectively (p=0.011). 51 local recurrences (41%) were true recurrences by location and histology. In the SL group, 78% had a documented discussion (consideration for SL vs. SM) with a surgeon/oncologist/radiation oncologist prior to surgical decision, and 70% underwent a breast MRI before final decision. Only 45% in the SM group had a discussion and 59% underwent MRI before the decision.

Following surgery for their recurrence, sixteen women (34%) of SL group underwent re-irradiation (partial breast RT) and 20 (27%, p=0.04) in the SM group (chest wall scar).

For the SL and SM cohorts, 8 and 10 patients (17%, 13.5%, p=0.22) respectively, developed subsequent local recurrence as a 3rd event. The median DFI between 2nd and 3rd recurrence for SL and SM was 6.5 and 15.5 years, respectively (p=0.081).

In a multivariate analysis, age at 1st diagnosis, T at 1st and 2nd recurrence, number of dissected/+ve LN, grade, type of axillary surgery as well as neo/adjuvant chemotherapy and HER2 status (both in primary and at recurrence), had no effect on 2nd recurrence occurrence for both groups; however, in MVA, undergoing SL had higher chances of having a 2nd recurrence (3rd event), p=0.020. Having re-irradiation following SL did not protect against 2nd recurrence (3rd event, p=0.42).

At a median follow-up of 14 years, 95.7% of SL patients are alive, NED, 85% are mastectomy free. 84% of patients who opted for SM are alive, NED.

Conclusions: Salvage lumpectomy following IBTR, while associated in MVA with higher second local recurrence rate than SL is not associated with inferior survival. With survival &gt;95% at 14 years in the SL cohort, salvage lumpectomy with or without re-radiation, in a selected population (unifocal T), represents an acceptable treatment option for patients in order to delay time to mastectomy and keep the original breast without reducing BC survival. Both options should be discussed prior to any surgical decision.

Citation Format: Sellam Y, Akiva Ben David M, Galper S, Dromi Shahadi I, Zippel D, Symon Z, Gelernter I. Local recurrence of breast cancer: Salvage lumpectomy as a safe option for local treatment [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-12-07.

Laparoscopic sleeve gastrectomy as a revisional option after gastric band failure

BACKGROUND

Laparoscopic adjustable gastric banding (LAGB) is an effective bariatric procedure with low morbidity and mortality. Unfortunately, it is fraught with high failure rates in long-term follow-up. Laparoscopic sleeve gastrectomy (LSG) is an emerging procedure, quickly gaining momentum in the arsenal of bariatric practice as a first step toward gastric bypass/biliopancreatic diversion or as a stand-alone operation. Recently, it has been described as a revisional option for previous bariatric surgery failures. We report our early experience with LSG as a revisional procedure for failed LAGB.

METHODS

From January 2007 to April 2010, 46 patients, who had undergone LAGB, underwent LSG. Patient demographics, reason for band removal, interval between removal and LSG, operative times, estimated blood loss, complications, length of hospital stay, and percent of excess weight loss were collected.

RESULTS

Of the 46 patients, 20 (43%) had their bands removed before LSG (median time interval, 2 years; range, 2 months to 9 years); the rest had concomitant band removal and LSG. Twelve patients were men (26%). Mean age and BMI were 40 (range, 20-60) years and 43.1 kg/m(2) (range, 33-57), respectively. In two cases, surgery was converted to an open procedure due to extensive adhesions related to previous surgeries. Median operative time, estimated blood loss, and length of hospital stay were 118 (range, 70-250) minutes, 41 (range, 5-600) ml, and 3 (range, 1-100) days, respectively. Major morbidity was encountered in three patients (6%; leak in 2 and bleeding in 1). There were no mortalities. Mean follow-up time for our cohort is 17 (range, 1-39) months. Percent of excess weight loss at 2, 6, 12, 24, and 36 months was 24, 37, 53, 51, and 48%, respectively.

CONCLUSIONS

Our results suggest that LSG is safe, feasible, and effective as a revisional procedure for failed LAGB and can be considered as an appealing option in these cases. Larger series and longer follow-up are needed to confirm this.

Clinical responses in a phase II study using adoptive transfer of short-term cultured tumor infiltration lymphocytes in metastatic melanoma patients

PURPOSE

Adoptive cell therapy with autologous tumor-infiltrating lymphocytes (TIL) has shown promising results in metastatic melanoma patients. Although objective response rates of over 50% have been reported, disadvantages of this approach are the labor-intensive TIL production and a very high drop-out rate of enrolled patients, limiting its widespread applicability. Previous studies showed a clear correlation between short TIL culture periods and clinical response. Therefore, we used a new TIL production technique using unselected, minimally cultured, bulk TIL (Young-TIL). The use of Young-TIL is not restricted to human leukocyte antigen (HLA)-A2 patients. The purpose of this study is to explore the efficacy and toxicity of adoptively transferred Young-TIL following lympho-depleting chemotherapy in metastatic melanoma patients, refractory to interleukin-2 and chemotherapy.

EXPERIMENTAL DESIGN

Young-TIL cultures for 90% of the patients were successfully generated, enabling the treatment of most enrolled patients. We report here the results of 20 evaluated patients.

RESULTS

Fifty percent of the patients achieved an objective clinical response according to the Response Evaluation Criteria in Solid Tumors, including two ongoing complete remissions (20+, 4+ months) and eight partial responses (progression-free survival: 18+, 13+, 10+, 9, 6+, 4, 3+, and 3 months). All responders are currently alive. Four additional patients showed disease stabilization. Side effects were transient and manageable.

CONCLUSION

We showed that lympho-depleting chemotherapy followed by transfer of short-term cultured TIL can mediate tumor regression in 50% of metastatic melanoma with manageable toxicity. The convincing clinical results combined with the simplification of the process may thus have a major effect on cell therapy of cancer.

Delayed breast cellulitis following breast conserving operation

A complication of breast conservation, which has been increasingly reported in the literature, is 'delayed cellulitis' in the treated breast. This is to be distinguished from wound infection in the breast following lumpectomy. This study reports 16 cases diagnosed with delayed cellulitis following breast conserving surgery, unresponsive to antibiotic therapy. Diagnostic criteria included: pain, erythema and edema in the operated breast. Symptoms appeared up to 10 months after surgery and time to resolution was seven and a half months. No patients had positive cytology and bacteriology tests were negative. Thirteen patients were observed, and three patients were treated with antibiotics with no apparent immediate effect. The appearance of breast cellulitis after surgery poses a problematic diagnostic and management dilemma. It is important to distinguish between this entity and infection, or inflammatory carcinoma. The picture may be attributed to impairment or occlusion of the lymphatic circulation in the breast. This seems to be a newly defined complication with an incidence of 3-5%.

Stromal extracellular matrix reduces chemotherapy-induced apoptosis in colon cancer cell lines

Several studies have shown that extracellular matrix reduces chemotherapeutic drugs-induced apoptosis in small cell lung cancer cells, myelomas and gliomas. We have investigated the protective effect of defined extracellular matrix components and of extracellular matrix from different cell types (fibroblasts, hepatocytes and intestinal epithelial cells) on the toxicity of three types of chemotherapeutic drugs on colon cancer cells. Human colon cancer cell lines LS174T and LiM6 were plated on plastic, on hepatocyte-derived ECM or on stromal ECM and in the presence of the antimetabolite 5-fluorouracil (5-FU). the topoisomerase I inhibitor camptothecin and the topoisomerase II inhibitor etoposide. We determined IC50 for the drugs for each of these culture conditions. We also determined the expression of the anti-apoptotic proteins bcl-2 and bcl-x (L) under these culture conditions. We found that stromal ECM protected LiM6 cells from the toxicity of etoposide and LS174T, but not LiM6 cells, from the toxicity of camptothecin. Collagen 1, fibronectin and fibroblast-derived ECM rendered LiM6 cells, but not LS174T, more sensitive to the harmful effect of 5-FU. Both colon cell lines had increased expression of anti-apoptotic proteins bcl-2 and bcl-x(L) when cultured on the various ECMs and with the drugs, but there was no correlation between a protective ECM effect and expression of the anti-apoptotic proteins. Stromal-derived ECM may protect colon cancer cells from etoposide and camptothecin-induced apotosis, through a mechanism that is not bcl-2 or bcl-x(L) dependant.

Positive margins of breast biopsy: is reexcision always necessary?

BACKGROUND AND OBJECTIVES

Breast-conserving surgery requires excision of all gross tumor and subsequent radiation therapy. It is generally accepted that the presence of microscopically positive margins requires reexcision. The goal of this study was to identify characteristics that distinguish breast biopsy specimens with positive margins that when reexcised are free from residual tumor. This population of patients may benefit from breast irradiation only, without the need for another surgical procedure.

METHODS

One hundred and fifteen of 395 cancer-proven biopsies had positive surgical margins and were treated with reexcision or mastectomy. Sixty-seven of these were negative for residual tumor and 48 were positive for residual tumor. Evaluation for tumor type, tumor size, grade, presence of vascular invasion, volume of the biopsy specimen, true positivity and the number of positive margins, multifocality of the tumor, and type of anesthesia was done by univariate and multivariate analysis.

RESULTS

Univariate and multivariate analysis revealed that factors associated with a positive reexcision included margin status, method of detection, histologic appearance, and type of anesthesia used.

CONCLUSION

These results suggest that small, clinically detectable unifocal tumors could be treated without the need for a further excision. Eradication of microscopic residual tumor could be done by irradiation only, sparing the patient an additional surgical procedure.

Revision hip arthroplasty in patients with a history of previous malignancy

BACKGROUND AND OBJECTIVES

The potential association between implants and malignancy has been discussed in the literature, but never as a cause of loosening of joint arthroplasty.

METHODS

The records of all patients who underwent revision arthroplasty at our institution between 1992 and 1995 were reviewed.

RESULTS

Among 93 patients who underwent revision hip arthroplasties, 11 (11.8%) had a history of previous malignancy. At surgery, in 2 of these patients, metastasis was found to be the cause of loosening in the affected hip.

CONCLUSIONS

When revision hip arthroplasty is considered, patients with a history of malignancy require attenuated pre-, intra-, and postoperative workup. Management algorithm in such cases is proposed.

Sentinel lymph node involvement--a predictor for axillary node status with breast cancer--has the time come?

AIMS

Axillary node dissection for breast cancer is important for staging and its prognostic value. Sentinel nodes are defined as the first nodes into which the primary cancer drains. This study investigates whether identification, removal and pathological examination of these nodes indicates whether the completion of axillary lymphadenectomy is required.

METHODS

Using a vital dye injected at the primary tumour site, we were able to identify sentinel nodes in 96 out of 98 women examined.

RESULTS

An average number of 2.7 +/- 1.2 nodes per patient were identified as sentinel nodes. In 83% of cases there was a correlation between the involvement of the sentinel nodes and the rest of the axillary nodes. In 14% of patients the sentinel nodes were the only nodes involved with tumour. In three cases the sentinel nodes were negative, but other axillary nodes were tumour-positive.

CONCLUSION

The major problem in routine application of this method to the decision to perform axillary lymph node dissection (ALND) is the time needed for pathological identification of lymph node involvement by tumor.

Aprotinin improves hemostasis after cardiopulmonary bypass better than single-donor platelet concentrate

Platelet transfusion and aprotinin administration improve platelet function and clinical hemostasis after extracorporeal circulation. To compare two methods of improving postoperative hemostasis, we preoperatively randomized 40 patients undergoing various open heart procedures into two groups. Group A included 20 patients who, immediately after bypass, received single-donor plateletpheresis concentrates collected from ABO-compatible donors (Baxter Autopheresis-C System). They were compared with 20 patients who received high-dose aprotinin (6 x 10(6) KIU) before and during cardiopulmonary bypass (group B). Group A patients showed significantly higher platelet count after single-donor plateletpheresis concentrate transfusion (157 +/- 36 x 10(9)/L compared with 118 +/- 42 x 10(9)/L (p < 0.05). However, platelet aggregation on extracellular matrix was better in group B (3.4 +/- 0.7 versus 2.8 +/- 0.9; p < 0.05). Total 24-hour blood loss and exposure to homologous blood products were significantly less in group B (396 +/- 125 mL and 1.1 +/- 1.6 units compared with 617 +/- 233 mL and 5.4 +/- 3.4 units; p < 0.01). Despite higher platelet count in patients after single-donor plateletpheresis concentrates transfusion, hemostasis in patients receiving aprotinin is better due to improved platelet function.

Abnormal macrophages and NK cell cytotoxicity in human systemic lupus erythematosus and the role of interferon and serum factors

Macrophage (MO) and natural killer (NK) cell mediated cytotoxicity to K562 target cells were strikingly decreased in patients with systemic lupus erythematosus (SLE). SLE NK cells failed to release soluble factor(s) for lysing the targets. IFN-induced enhancement of both types of cytotoxicity was impaired. NK cells from healthy subjects kept their activity in culture with or without IFN for more than six days whereas SLE NK cell activity declined to zero at day 3. So, the increased IFN level of many SLE patients and a possible prior IFN priming effect seemed unrelated to the insensitivity to exogenous IFN in vitro. Inhibition factor(s) of SLE serum suppressed NK cytotoxicity in the presence of IFN whereas IFN sensitivity of MO remained unaffected indicating the complex regulation by serum components of immune reactions.

Studies on the mechanism of macrophage cytotoxicity

The interactions with tumor target cells of resident and BCG-activated murine peritoneal macrophages (M phi) as well as of BCG-activated M phi additionally stimulated by a lymphokine-like factor were investigated in order to get some insight into the cytolytic process mediated by activated M phi. The lymphokine-like factor enhancing the cytotoxicity of BCG-activated M phi (MCF) was isolated and partially purified from cell-free fluid of rat Zajdela ascites hepatoma. M phi cytotoxicity was determined by a modified 51Cr release assay. Scanning and transmission electron microscopic findings suggested a two-step mechanism of target cell lysis: a first step of specific attachment of processes of M phi on the target cell surface and a second step with transport of lysosome-like vesicles to the target cells obviously with liberation of these vesicles in the immediate vicinity of target cells resulting in a local accumulation of cytolytic substances. This interpretation was supported by findings after treatment of interacting effector and target cells with amphotericin B and bestatin which substances were modifying M phi cytotoxicity. MCF caused only an augmentation of M phi cytotoxicity without qualitative differences to the cytolytic action of merely BCG-activated M phi.