Fatal pulmonary tumor embolization following peritoneovenous shunting for malignant ascites

Neoplastic embolization to systemic and pulmonary arteries

OBJECTIVE

Arterial neoplastic emboli are uncommon, accounting for <1% of thromboemboli in the current literature. Nonetheless, this event may be associated with significant morbidity and mortality. Herein, we report a series of 11 cases of arterial neoplastic emboli from a single tertiary care center along with a comprehensive review of the literature to date. The aim of this study was to document the incidence, clinical presentations, and complications of arterial neoplastic emboli as well as to highlight the importance of routine histologic examination of thrombectomy specimens.

METHODS

Pathology archives from a single tertiary care institution were queried to identify cases of surgically resected arterial emboli containing neoplasm (1998-2014). Histopathology was reviewed for confirmation of diagnosis. Patient demographics and oncologic history were abstracted from the medical record. Comprehensive literature review documented 332 patients in 275 reports (1930-2016).

RESULTS

Eleven patients (six men) with a median age of 63 years (interquartile range, 42-71 years) were identified through institutional archives. Embolism was the primary form of diagnosis in seven (64%) cases. Cardiac involvement (primary or metastasis) was present in more than half of the cohort. Comprehensive literature review revealed that pulmonary primaries were the most common anatomic origin of arterial neoplastic emboli, followed by gastrointestinal neoplasia. Cardiac involvement was present in 18% of patients, and sentinel identification of neoplasia occurred in 30% of cases. Postmortem evaluation was the primary means of diagnosis in 27%.

CONCLUSIONS

This study highlights the importance of routine histopathologic evaluation of embolectomy specimens in patients with and without documented neoplasia.

The current and future management of malignant ascites

Malignant ascites occurs in association with a variety of neoplasms. It is a frequent cause of morbidity and presents significant problems for which there are no clear management guidelines. In this article we discuss various modalities which are available including diuretic therapy, paracentesis, peritoneovenous shunts and intraperitoneal chemotherapy. There are no randomized trials of diuretic drugs to assess their efficacy in malignant ascites. Phase II data suggest that they are effective in approximately one-third of patients with malignancy, and their efficacy may be determined by plasma renin/aldosterone concentrations. Paracentesis provides relief in up to 90% of patients; because of varying reports of hypovolaemia, some advocate simultaneous intravenous fluid infusion. Permanent percutaneous drains may prevent the need for repeated paracentesis, although there is potential for infection. A peritoneovenous shunt also prevents the need for repeated paracenteses, whilst maintaining normal serum albumin concentrations. Blockage occurs in 25% of shunts, which are contraindicated in the presence of heavily bloodstained ascites because of the risk of occlusion. The preclinical and clinical experience with anti-angiogenic agents such as the matrix metalloproteinase inhibitors and the VEGF antagonists suggests that these agents may have a role in the treatment of malignant ascites.

Treatment of chronic pleural effusion with pleuroperitoneal shunts in dogs: 14 cases (1985-1999)

OBJECTIVE

To describe complications and outcome associated with chronic nonseptic pleural effusion treated with pleuroperitoneal shunts in dogs.

DESIGN

Retrospective study.

ANIMALS

14 dogs.

PROCEDURE

Medical records at 4 veterinary schools were examined to identify dogs with chronic nonseptic pleural effusion that were treated by use of a pleuroperitoneal shunt between 1985 and 1999. Signalment, history, physical examination and laboratory findings, cause and type of pleural effusion, medical and surgical treatments, complications, and outcome were reviewed.

RESULTS

10 of 14 dogs had idiopathic chylothorax, and 4 had an identified disease. All but 1 dog with idiopathic chylothorax and 1 dog with chylothorax from a heart base tumor had unsuccessful thoracic duct ligation prior to pump placement. No intraoperative complications developed during shunt placement. Short-term complications developed in 7 of 13 dogs, necessitating shunt removal in 2 dogs and euthanasia in 1. Eight of 11 dogs with long-term follow-up developed complications; the overall mean survival time and the interval in which dogs remained free of clinical signs of pleural effusion were 27 months (range, 1 to 108 months) and 20 months (range, 0.5 to 108 months), respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

Pleuroperitoneal shunts can effectively palliate clinical signs associated with intractable pleural effusion in dogs. Numerous short- and long-term complications related to the shunt should be expected. Most complications can be successfully managed, but even when shunts are functional some treatments fail because of severe abdominal distension or massive pleural fluid production that overwhelms the functional capacity of the shunt.

Management of symptomatic malignant ascites with diuretics: two case reports and a review of the literature

Malignant ascites is a common complication of advanced cancer. It is associated with distressing symptoms and poor prognosis. Treatment may be aimed at the underlying cancer but is rarely successful. Therapeutic success for the available symptomatic treatment options for ascites is often limited. Control of symptomatic malignant ascites is possible with the use of diuretics in selected patients, is well tolerated, and should be tried first.

Malignant ascites. A comparison of peritoneovenous shunting and nonoperative management

BACKGROUND

Effective palliation of malignant ascites remains a difficult management problem.

METHODS

Eighty-five patients with malignant ascites were studied. Forty-two patients had peritoneovenous shunts (PVS) inserted (16 LeVeen, 17 single-valve Denver, 9 double-valve Denver).

RESULTS

Shunt patency was not related to the type of shunt, type of cancer, or any characteristic of the ascitic fluid. Ascites was controlled in 64% of patients with shunts and serum albumin levels were preserved. Survival and quality of life were not significantly different in comparison with those of patients treated by abdominal paracentesis.

CONCLUSIONS

PVS allowed many patients to be treated successfully outside the hospital and are indicated in carefully selected cases.

Pseudomyxoma peritonei of appendiceal origin. The Memorial Sloan-Kettering Cancer Center experience

BACKGROUND

Pseudomyxoma peritonei is a rare clinical entity in which the peritoneal surfaces and omentum are involved with diffuse gelatinous mucinous implants. It originates from ruptured mucinous tumors of the appendix or ovary.

METHODS

The authors examined the experience with 34 patients with pseudomyxoma peritonei seen at Memorial Sloan-Kettering Cancer Center from 1952-1989. Of these, 17 cases were identified to be of appendiceal origin.

RESULTS

All patients underwent celiotomy and cytoreduction. The median survival time from diagnosis was 75 months. It was found that long-term survival can be achieved by operation alone. When conditions do recur, chemotherapy may be valuable.

CONCLUSIONS

Pseudomyxoma peritonei of appendiceal origin is a rare low-grade malignancy. Initial treatment consists of cytoreduction in an attempt to render the patient locally disease-free. Long-term survival can be obtained by operation alone, even if gross disease is present at the end of the procedure. Systemic chemotherapy should be reserved for patients with proven recurrence.

Intraoperative blood salvage: medical controversies

Although a great deal has been learned about the medical aspects of intraoperative blood salvage, several fundamental medical issues remain controversial. As pressure increases to maximize the use of IBS, more research will be needed on the application of salvage techniques in cancer surgery and in the presence of bacterial contamination. The reintroduction of the use of devices that do not wash salvaged blood have reopened investigations into the effects of reinfusion of partially hemolyzed and partially clotted salvaged blood on coagulation, renal function, and cardiopulmonary performance. More studies are also needed so that empirically based standards of practice for the collection and storage of salvaged blood can be established. No longer confined to a few pioneering surgical departments, IBS is now widely practiced and likely to continue to grow rapidly. Knowledge and research of the medical issues surrounding its use will become increasingly valuable in transfusion medicine.

Peritoneovenous shunts palliate malignant ascites

Fifty-five peritoneovenous shunts (PVS) were implanted in 45 patients (29 LeVeen and 26 Denver shunts). Seventy-five percent of patients experienced relief of symptoms referable to their ascites. The mean survival time post-shunt placement was 33 weeks; however, considerable variation was noted in survival times for the various tumor types (pancreas 7 weeks, ovary 71 weeks). Significant alterations in coagulation parameters consistent with subclinical disseminated intervascular coagulation (DIC) were present in all patients with functioning shunts. These coagulation changes have proven reliable indicators of shunt patency. Shunt revision was necessary in 18 percent of patients. No significant difference in shunt patency was detected when Denver and LeVeen shunts were compared. This experience indicates that PVS offers effective palliation without undue morbidity for malignant ascites. The best results can be expected in those patients with ovarian and breast primary tumors. Because of the short time from onset of disabling ascites until death, PVS is not indicated in the majority of patients with pancreatic cancer.

Protein leak from normal vasculature due to human malignant ascites

Malignant ascites is an accumulation of protein rich fluid (a filtrate of whole blood) in the peritoneal cavity of patients with abdominal malignancies. The normal peritoneal microvasculature of the cremaster muscle of rats, with the nerve and blood supply intact, was visualized before and after exposure of the tissue to human malignant ascites fluid and to human plasma. In vivo fluorescent microscopy was used to quantitate leakage of fluorescent-tagged albumin. Exposure of the abluminal side of the vasculature to malignant ascitic fluid and plasma causes significant protein leakage from the small veins to the interstitial space. This suggests that the continued production of malignant ascites may be caused by a positive feedback system, which is related to factors present in a normal plasma filtrate. These factors can induce leakage of protein by an effect on the abluminal side of the normal peritoneal microvasculature.

Pulmonary tumor embolization after peritoneovenous shunting for malignant ascites

An 85-year-old woman with intractable malignant ascites secondary to ovarian carcinoma underwent peritoneovenous shunting (Denver shunt) in an attempt to alleviate the ascites. Implantation of the shunt resulted in massive embolization of tumor cells to the pulmonary vasculature. Postoperatively, she developed increasing hypoxia with progressive rises in pulmonary artery pressure, and died 48 hours after surgery as a result of occlusion of the pulmonary vascular bed by tumor emboli. This is the sixth reported instance of massive tumor embolization to the pulmonary circulation in patients with peritoneovenous shunting for malignant ascites.

Denver peritoneovenous shunting for malignant or cirrhotic ascites. A prospective consecutive series

A Denver peritoneovenous (PV) shunt was inserted in 54 consecutive patients for relief of malignant (24 patients) or cirrhotic (30) refractory ascites. The median age of both groups was 58 years, and the most frequent diagnoses were gastrointestinal (15) or ovarian (7) cancers and alcoholic cirrhosis (25). Median survival time was 1.7 and 3.5 months (range, 0.1-15.5 and 0.1-50.5), and the 1-month mortality 42% and 27%, respectively. Postoperative 24-h urinary output increased by 2-31, and the 1-week weight reduction was 8 and 11 kg, respectively, compared with before shunting. Complete shunt failure was encountered early in two patients, due to catheter malposition and clotting. Four more patients experienced transient failure, for an early dysfunction rate of 11%. A shunt-related operative mortality of 6% was caused by pulmonary oedema (two patients) and sepsis (one patient). Shunt malfunction intervened in almost half (6 of 14) of the cancer patients surviving 1 month but was relieved in all but 1. In 3 of 22 cirrhotic 1-month survivors, the Denver shunt had to be removed owing to clotting or sepsis (2 patients) or revised because of blockage. Seven patients with cirrhosis are alive a median of 18 months (range, 2-51) after PV shunt surgery. Side effects were detected in 22 patients (41%): thromboembolism (9 patients), sepsis (7), initially bleeding oesophageal varices (3), DIC syndrome (2), postoperative hepatic coma (2), ascitic leakage (2), and pulmonary oedema (2). Patients with gastrointestinal cancers or severe cardiac disease did not benefit from the procedure. A history of hepatic encephalopathy or a serum bilirubin level above about 100 mumol/l was a bad prognostic sign. We could confirm the reported considerable morbidity and mortality after PV shunting, but also its efficiency in certain cases. Careful patient selection and follow-up study, timing of operation, and adherence to technical details are mandatory to improve the results.

Peritoneovenous shunts in malignant ascites

A 51-year-old woman with malignant ascites secondary to hepatocellular carcinoma had a peritoneovenous (LeVeen) shunt inserted with effective control of ascites and amelioration of symptoms. The results of 12 recent series evaluating the efficacy of peritoneovenous shunts in the treatment of 198 patients with malignant ascites were reviewed. Peritoneovenous shunts effectively controlled malignant ascites in 77% of patients. Complications occurred in 25%, although the majority of these were related to shunt occlusion and transient congestive heart failure.

Successful treatment of pseudomyxoma peritonei of ovarian origin with cis-platinum, doxorubicin, and cyclophosphamide

Pseudomyxoma peritonei is a rare disease characteristically secondary to mucin-producing adenocarcinomas of the ovary and appendix. Though, as a rule, not invasive or metastatic, death occurs secondary to gastrointestinal dysfunction. This is the first case of pseudomyxoma peritonei secondary to an ovarian primary possibly cured by systemic cis-platinum, doxorubicin, and cyclophosphamide.

Surgical and pathologic complications associated with peritoneovenous shunts in management of malignant ascites

Forty-three peritoneovenous shunts have been inserted to palliate malignant ascites in 33 patients. Ascites was controlled for a time in every patient, but 18 shunts eventually blocked. Further shunt revision successfully controlled ascites until death in five of these patients and for prolonged periods in another five. The authors observed a marked difference between the performances of the two available shunts, but emphasize that the two groups of patients were not selected at random and therefore may not be comparable. Twelve postmortem examinations have been performed in the 33 patients to ascertain causes of shunt malfunction and to identify possible evidence of abnormal or accelerated tumor spread. The postmortem findings highlight great variability in the capacity of iatrogenically introduced showers of tumor cells to seed. There was a spectrum of tumor growth in the lung from a complete absence of tumor cells through dormant tumor clumps to developing metastases. The authors found no evidence either clinically or at autopsy, that the procedure had adversely affected the prognosis, except in one patient who died from pulmonary edema immediately after the operation.

Control of malignant ascites by peritoneovenous shunting

Twenty peritoneovenous shunts were inserted in 17 patients with intractable malignant ascites. The ascites was controlled without the need for further paracentesis abdominis in 13 patients. Four shunts blocked and three patients had second shunts inserted, but other complications were minor. Patients who benefited from the procedure included those with macroscopically light blood staining of the ascites and those with malignant cells in the ascitic fluid. Unless the ascites is heavily blood-stained or the patient's anticipated survival is less than 1 month, peritoneovenous shunting is indicated for the treatment of uncontrollable malignant ascites.

Peritoneovenous shunt for intractable malignant ascites. A single case report of metastatic peritoneal mesothelioma implanted via LeVeen shunt

A patient with malignant ascites refractory to conservative and conventional therapy underwent peritoneovenous shunt. The shunt provided palliation for 7 months with relief of nausea, vomiting, and anorexia and with decrease of weight and abdominal girth. There was no need for repeated paracenteses, which had been required before shunting. The patient's strength increased. However, increasing shortness of breath developed approximately 6 to 7 months after insertion of the shunt. The shunt was associated with extensive metastatic dissemination of peritoneal mesothelioma to both lungs. It is suggested that peritoneal mesothelioma is a contraindication for peritoneovenous shunt.

Clinicopathological observations on metastasis in man studied in patients treated with peritoneovenous shunts

Fourteen patients with inoperable cancer treated with peritoneovenous shunts for malignant ascites were studied post mortem. Clinical observations and findings at necropsy indicated that peritoneovenous shunting does not result in the establishment of clinically important haematogenous metastases and that metastases do not necessarily develop even when large numbers of viable tumour cells regularly enter the blood. Peritoneovenous shunting provides a unique opportunity for collecting data on the spread of tumours in man.

Peritoneovenous shunts in the management of malignant ascites

Peritoneovenous shunts have been inserted into 26 patients to control malignant ascites. All benefitted and most required no further paracentesis until death from progressive malignancy. Shunt blockage, which is the major problem at present, occurred in 8 patients. Five patients suffering from far advanced malignancy died within a month of operation. There was no clinical evidence of enhanced tumour spread or disseminated intravascular coagulation. We do not consider that the procedure is the first line of management, neither has it much to offer the patient with viscous, bloodstained or loculated ascites. We suggest criteria which help to identify the patient most likely to benefit from a peritoneovenous shunt.

Selection of patients with malignant ascites for a peritoneovenous shunt

Twenty-two patients with intractable malignant ascites who received a peritoneovenous shunt were studied. We found that the peritoneovenous shunt functioned longer in patients whose ascitic fluid was negative for malignant cells. The median shunt survival in alive patients in the negative cytologic group was 140 days compared to 26 days in the positive cytologic group (P = 0.01). The overall survival of these patients was poor, with a median of 32 days. Median survival of patients with positive cytologic results (26 days) was significantly worse than for the cytologically negative group (80 days; P = 0.05). The incidence of tumor emboli, confirmed at autopsy, was estimated to be about 5%. Seventy-five percent of all complications occurred in the group of patients with a positive cytologic result. We conclude that a positive ascites fluid cytologic finding is a relative contraindication to placement of a peritoneovenous shunt since this is associated with early shunt failure, postoperative coagulopathy, infection, and tumor emboli. However, since the serious complication rate is only 4% and tumor emboli rate 5%, peritoneovenous shunting in symptomatic patients with cytologically negative malignant ascites is a useful palliative procedure.