Functional hyposplenia after splenic irradiation for Hodgkin's disease

Spleen as an organ at risk in adjuvant chemoradiotherapy for gastric cancer: a retrospective dosimetric study

Introduction:

This study aimed to determine the radiation dose to the spleen in adjuvant chemoradiotherapy for gastric cancer, resulting in haematological toxicities.

Methods:

This retrospective analysis of a prospectively maintained database was conducted at a tertiary referral cancer centre. All patients with biopsy-proven non-metastatic gastric adenocarcinoma planned for adjuvant chemoradiotherapy from January 2017 to December 2021 were included. The mean dose to the spleen (Dmean) was estimated and correlated with the development of haematological toxicities.

Results:

The mean spleen volume was 186·65 cc. The Dmean to the spleen was 35·35 Gy (20–42 Gy). Grade 3 leukopenia was observed in 67%, grade 4 in 15%, and grade 3 thrombocytopenia was noted in 41% of patients. Radiotherapy (RT) dose > 35·5 Gy to the spleen resulted in ≥ grade 3 leukopenia. RT dose ≥ 36·5 Gy resulted in grade 3 thrombocytopenia. The occurrence of leukopenia and thrombocytopenia was also affected by the location of the primary gastric cancer (higher incidence in distal than in proximal tumours).

Conclusion:

The spleen should be considered as an important organs at risk during adjuvant RT for gastric cancer. Dmean to the spleen should be < 35·5 Gy to prevent major haematological toxicities.

Splenic irradiation contributes to grade ≥ 3 lymphopenia after adjuvant chemoradiation for stomach cancer

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Severe lymphopenia occurs commonly after adjuvant chemoradiation for gastric cancer.

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High splenic radiation doses increase the chances of severe lymphopenia.

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Severe lymphopenia predicts a poorer overall survival and higher risk of infections.

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The spleen is not routinely considered an organ-at-risk with dosimetric constraint.

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Applying dose constraints to the spleen might lower the risk of severe lymphopenia.

Introduction

Adjuvant chemoradiation therapy (CRT) in gastric cancer inevitably results in an unintentional spleen radiation dose. We aimed to determine the association between the spleen radiation dose and the observed severity of lymphopenia which may affect the clinical outcomes (survival time and infection risk).

Methods

Patients who received adjuvant CRT for gastric cancer between January 2015 and December 2020 were analyzed. The splenic dose-volume histogram (DVH) parameters were reported as mean splenic dose (MSD) and percentage of splenic volume receiving at least × Gray (Gy). Peripheral blood counts were recorded pre- and post-CRT. The development of severe (Common Terminology Criteria for Adverse Events, version 5.0, grade ≥ 3) post-CRT lymphopenia (absolute lymphocyte count [ALC] < 0.5 K/μL) was assessed by multivariable logistic regression using patient and dosimetric factors. Overall survival (OS), recurrence-free survival (RFS), and cumulative incidence of infectious events were estimated and analyzed using the Cox model or competing risk analysis.

Results

Eighty-four patients with a median follow-up duration of 42 months were analyzed. Pre- and post-CRT median ALC values were 1.8 K/μL (0.9–3.1 K/μL) and 0.9 K/μL (0.0–4.9 K/μL), respectively (P < 0.001). MSD > 40 Gy (odds ratio [OR], 1.13; 95 % confidence interval [CI], 1.01–1.26; P = 0.041), sex (OR for male to female, 0.25; 95 % CI, 0.09–0.70; P = 0.008), and baseline absolute neutrophil count (OR per 1 unit increase, 1.61; 95 % CI, 1.02–2.58; P = 0.040) were associated with the development of severe post-CRT lymphopenia, which was a risk factor for poorer OS (hazard ratio [HR] = 2.47; 95 % CI, 1.24–4.92; P = 0.010) and RFS (HR = 2.27; 95 % CI, 1.16–4.46; P = 0.017). The cumulative incidence of infections was higher among severe post-CRT lymphopenia patients (2.53, 95 % CI, 1.03–6.23, P = 0.043).

Conclusion

High splenic radiation doses increase the odds of severe post-CRT lymphopenia, an independent predictor of lower OS and higher risks of recurrence and infections in gastric cancer patients receiving adjuvant CRT. Therefore, optimizing the splenic DVH parameters may decrease the risk of severe post-CRT lymphopenia.

Coincidental splenic irradiation and risk of functional hyposplenism in oesophageal cancer treatment

INTRODUCTION

Definitive chemoradiotherapy (dCRT) and radical radiotherapy are central to the management of distal oesophageal carcinoma. This study sought to establish whether the spleen receives a significant incidental radiation dose when treating distal oesophageal carcinoma with the standardised dCRT or radical radiotherapy doses.

METHODS

In this single-centre retrospective study, all patients (n = 34) with distal oesophageal cancer, treated with either dCRT or radical radiotherapy over an 18-month period using a volumetric modulated arc therapy (VMAT) planning technique, were included. The median age was 74 years old: 56% were male; 50% (n = 17) had adenocarcinoma and 41% (n = 14) had squamous carcinoma. The majority (79%) received dCRT with a prescribed dose of 50 Gy in 25 fractions while the other 21% of patients were treated with radical radiotherapy alone (55 Gy in 20 fractions). The spleen was retrospectively contoured by one physician, and the V_{10 Gy} and mean splenic dose (MSD) were calculated using Eclipse planning software.

RESULTS

The median MSD was 14.4 Gy with a range of 0.75-28.3 Gy. The median V_{10 Gy} was 62.7%. Of the cohort, 67.6% received an MSD of more than 10 Gy.

CONCLUSIONS

Two-thirds of the patients received a dose of more than the 10 Gy. A review of the literature suggests that higher splenic radiation doses may increase the long-term risk of infection and impact on other outcomes. This study provides important evidence that the spleen receives a significant dose of radiation when treating distal oesophageal cancer and should be considered as an organ at risk.

Late Infection-Related Mortality in Asplenic Survivors of Childhood Cancer: A Report From the Childhood Cancer Survivor Study

Purpose Infection-related outcomes associated with asplenia or impaired splenic function in survivors of childhood cancer remains understudied. Methods Late infection-related mortality was evaluated in 20,026 5-year survivors of childhood cancer (diagnosed < 21 years of age from 1970 to 1999; median age at diagnosis, 7.0 years [range, 0 to 20 years]; median follow-up, 26 years [range, 5 to 44 years]) using cumulative incidence and piecewise-exponential regression models to estimate adjusted relative rates (RRs). Splenic radiation was approximated using average dose (direct and/or indirect) to the left upper quadrant of the abdomen (hereafter, referred to as splenic radiation). Results Within 5 years of diagnosis, 1,354 survivors (6.8%) had a splenectomy and 9,442 (46%) had splenic radiation without splenectomy. With 62 deaths, the cumulative incidence of infection-related late mortality was 1.5% (95% CI, 0.7% to 2.2%) at 35 years after splenectomy and 0.6% (95% CI, 0.4% to 0.8%) after splenic radiation. Splenectomy (RR, 7.7; 95% CI, 3.1 to 19.1) was independently associated with late infection-related mortality. Splenic radiation was associated with increasing risk for late infection-related mortality in a dose-response relationship (0.1 to 9.9 Gy: RR, 2.0; 95% CI, 0.9 to 4.5; 10 to 19.9 Gy: RR, 5.5; 95% CI, 1.9 to 15.4; ≥ 20 Gy: RR, 6.0; 95% CI, 1.8 to 20.2). High-dose alkylator chemotherapy exposure was also independently associated with an increased risk of infection-related mortality (RR, 1.9; 95% CI, 1.1 to 3.4). Conclusion Splenectomy and splenic radiation significantly increase risk for late infection-related mortality. Even low- to intermediate-dose radiation exposure confers increased risk, suggesting that the spleen is highly radiosensitive. These findings should inform long-term follow-up guidelines for survivors of childhood cancer and should lead clinicians to avoid or reduce radiation exposure involving the spleen whenever possible.

Radiation-induced dose-dependent changes of the spleen following postoperative chemoradiotherapy for gastric cancer

BACKGROUND AND PURPOSE

Abdominal (chemo-)radiotherapy is associated with dose-limiting toxicity of various normal structures. The purpose of this retrospective study was to investigate radiation-induced changes of the spleen and their clinical consequences.

PATIENTS AND METHODS

In gastric cancer patients treated with postoperative chemoradiotherapy, the spleen size and its functions were assessed at follow-up by spleen volume on CT-scan, serum leucocytes/thrombocytes, and the occurrence of infectious events consisting of pneumonia and fatal sepsis. To evaluate the effect of radiation dose, mixed effects and Cox regression models were used.

RESULTS

Forty-six out of 90 consecutive patients treated from 2006 to 2011 were evaluable. All patients received 45 Gy in 25 fractions with concurrent capecitabine (n=8), and capecitabine/cisplatin (n=38). Median Dmean to the spleen was 40 Gy (range 32-46). Mean relative spleen volume reduced to 37% (95% CI 32-42%) at 4-year follow-up, which was most strongly associated to the V44 (p<0.001). Median follow-up time was 67 (95% CI 57-78) months. Eleven patients had 13 pneumonias and 3 fatal sepsis. No association with dosimetric parameters was observed.

CONCLUSIONS

In postoperative chemoradiotherapy for gastric cancer, the spleen received a high radiation dose. This resulted in a progressive, radiation dose-dependent reduction of spleen volume. Pneumonia and fatal sepsis occurred frequently, possibly as a result of functional hyposplenia.

Practical review of immunizations in adult patients with cancer

Compared with the general population, patients with cancer in general are more susceptible to vaccine-preventable infections, either by an increased risk due to the malignancy itself or immunosuppressive treatment. The goal of immunizations in these patients is therefore to provide protection against these infections, and to decrease the number of vulnerable patients who can disseminate these organisms. The proper timing of immunization with cancer treatment is key to achieving better vaccine protection. As the oncology field continues to advance, leading to better quality of life and longer survival, immunization and other aspects of preventive medicine ought to move to the frontline in the care of these patients. Herein, we review the vaccines most clinically relevant to patients with cancer, as well as special cases including vaccines after splenectomy, travel immunization and recommendations for family members.

Hyposplenism: A comprehensive review. Part I: Basic concepts and causes

Hyposplenism is not a rare condition and can complicate a remarkable number of illnesses. The two most time-honored diseases associated with the development of hyposplenism are sickle cell anemia and celiac disease. Hyposplenism is relatively easy to recognize by typical changes observed on the peripheral blood smear; including Howell-Jolly bodies, monocytosis, lymphocytosis, and increased platelet counts. Diagnosis can be confirmed by pitted RBC counts or 99Tc-labelled radiocolloid scan of the spleen; wherever available. Diagnosis needs to be made promptly to institute pneumococcal vaccination in a timely fashion and to recognize and treat bacterial infections promptly and aggressively because of the tendency of hyposplenic subject to develop fatal invasive disease. Overwhelming pneumococcal sepsis accounts for the major mortality cases in hyposplenic subjects; however severe infections with other encapsulated bacteria and protozoa have been reported. Hyposplenic individuals may also be at a higher risk for vascular, autoimmune and thrombotic diseases and they may have a higher risk of developing solid tumors. The commonly used pneumococcal polysaccharide vaccine is ineffective in asplenic subjects, because it requires the presence of IgM memory B cells, and should be given before splenectomy. In splenectomized, and functionally hyposplenic subjects, the pneumococcal conjugate vaccine is more effective, because it utilizes a T cell dependent mechanism, and should be the preferred vaccine in these circumstances.

Splenocolonic fistula following non-operative management of splenic rupture

Non-operative management has become the preferred treatment for splenic trauma in the absence of haemodynamic instability. The reported complications of non-operative management of splenic trauma may include pseudoaneurysm formation, delayed splenic rupture and splenic abscess formation. Splenocolonic fistula is a finding that has only previously been described in association with Crohn’s disease, pancreatitis, malignancy and haematological disorders. We present the case of a 16-year-old male who suffered a blunt traumatic injury to the spleen, was haemodynamically stable and successfully managed non-operatively. He represented 1 month later following a single episode of per-rectum bleeding. A CT scan of his abdomen revealed a pseudoaneurysm within the spleen, a splenic abscess and a splenocolonic fistula. He proceeded to emergency laparotomy for splenectomy and colonic resection and had an uneventful recovery. The history of management of blunt traumatic splenic injury is discussed, along with the associated risks of operative and conservative management. Methods predicting the success of non-operative management are explored, along with their application and relevance to this particular case.

Survivorship: childhood cancer survivors

Late effects of therapy for childhood cancer are frequent and serious. Fortunately, many late effects are also modifiable. Proactive and anticipatory risk-based care can reduce the frequency and severity of treatment-related morbidity. The primary care clinician should be an integral component in risk-based care of survivors. Continued communication between the "late effects" staff at the cancer center and the primary care clinician is essential for optimum care of this high-risk population.

Howell-Jolly body counting as a measure of splenic function. A reassessment

Non-surgical and surgical asplenia predisposes to fatal infections; therefore, simple, non-invasive and repeatable tests for assessing splenic function are required, even in non-specialized medical institutions. Howell-Jolly bodies are the most characteristic peripheral blood abnormality after splenectomy, but their counting is not considered a reliable measure of splenic function. In this study, in a group of splenectomized subjects and of patients with non-surgical hyposplenism, we have compared counting of Howell-Jolly bodies, stained by both the May-Grünwald/Giemsa method and the Feulgen reaction, with pitted cell counting which is considered a reliable technique for the assessment of splenic hypofunction. A significant correlation has been found between Howell-Jolly body counts, stained by either technique, and pitted cell counts (P less than 0.0001). Through Howell-Jolly bodies were never detectable when pitted cell counts fell between 4 and 8%, values consistent with a very mild splenic hypofunction, for pitted cell counts above 8% their increase was always associated with increasing Howell-Jolly body counts. These data suggest that, although pitted cell counting represents a more sensitive method for evaluating splenic function, Howell-Jolly body counting may still be regarded as a simple and reliable technique for identifying and monitoring those cases associated with a real risk of overwhelming infections.

[Immunization for children treated for solid tumors: what are the guidelines?]

There is no agreement on immunization of children treated with chemotherapy (CT) for solid tumors. Based on a review of the literature, we have attempted to establish guidelines on this subject. Except for hepatitis B vaccine, there is no argument to support the use of vaccine during CT. After a standard CT, a 3-month washout period appears to be necessary before starting an immunization program for a child not previously vaccinated, or to proceed with the recommended booster injections for diphteria anatoxin, tetanus vaccine, poliomyelitis inactivated vaccine, pertussis vaccine, and haemophilus influenza type b vaccine if the child is less than 5 years old. For mumps, measles, and rubella live vaccines, a longer post-CT washout of 6 months is suggested for the initial immunization, or for a revaccination of a child proved to be negative for all three serologies. Following high-dose CT a minimal 12-months term and a normalization of the blood lymphocytes count is necessary before planning booster injections once having checked for antidiphteria, tetanic, polio, measles, mumps, rubella and +/- haemophilus antibody titles. We don't find any reason to recommend a systematic varicella immunization in pediatric oncology. Pneumococcal vaccine is recommended in case of asplenia. Any other vaccination (BCG, influenza, yellow fever) must be evaluated individually.

Decision analysis on alternative treatment strategies for favorable-prognosis, early-stage Hodgkin's disease

PURPOSE

To compare the therapeutic outcomes of various treatment strategies in early-stage, favorable-prognosis Hodgkin's disease (HD) using methods of decision analysis.

METHODS

We constructed a decision-analytic model to determine the life expectancy and quality-adjusted life expectancy for a hypothetical cohort of clinically or pathologically staged 25-year-old patients with early-stage, favorable-prognosis HD treated with varying degrees of initial therapy. Markov models were used to simulate the lifetime clinical course of patients, and baseline probability estimates were derived from published study results.

RESULTS

Among patients with pathologic stage (PS) I to II, mantle and para-aortic (MPA) radiotherapy was favored over combined-modality therapy (CMT), mantle radiotherapy, and chemotherapy by 1.18, 1.33, and 1.55 years, respectively. For patients with clinical stage (CS) I to II, the treatment options of MPA-splenic radiotherapy, CMT, and chemotherapy yielded similar survival outcomes. Sensitivity analysis showed that the decision between CMT and MPA-splenic radiotherapy was highly influenced by the precise values of the estimates of treatment efficacy and long-term morbidity, the quality-of-life value assigned to the postsplenic irradiation state, and the time discount value used in the model. Probabilistic sensitivity analysis demonstrated that even if future studies doubled the precision of the estimates of the treatment-related variables, it would be impossible to demonstrate the superiority of one treatment over the other.

CONCLUSION

Our model predicted that on average, MPA radiotherapy was clearly the preferred treatment for PS I to II patients. For CS I to II patients the treatment decision is a toss-up between MPA-splenic radiotherapy and CMT, emphasizing the importance of patient preference exploration and shared decision making between patient and physician when choosing between treatments.

Long-term decrease of CD4+CD45RA+ T cells and impaired primary immune response after post-traumatic splenectomy

Congenital or acquired absence of the spleen and functional hyposplenism are associated with abnormalities of host defence such as an increased susceptibility to infection with encapsulated bacteria. The effects of the lack of the spleen on cell-mediated immunity are largely unknown. In the present study we have investigated peripheral blood lymphocyte subpopulations in healthy adults who had undergone splenectomy because of severe abdominal trauma > 4 years before the study. The results show a significant reduction in the percentage of CD4+ T cells due to a selective and long-term decrease in the percentage of CD4+CD45RA+ lymphocytes, the CD4+ T-cell subset mainly involved in primary immune responses to newly encountered antigens. Levels of the reciprocal CD45RO+CD4+ T-cell subset were comparable between splenectomized and control individuals, as were lymphoproliferative responses and IFN-gamma production to recall antigens. Decreased levels of CD4+CD45RA+ cells were accompanied by an impairment in primary immune responsiveness, as assessed by investigating T-cell proliferation to stimulation with keyhole limpet haemocyanin and by measuring antibody responses following primary immunization with a clinically relevant T-dependent antigen, hepatitis A vaccine, in vivo. These findings suggest a possible role of the spleen in the generation, maintenance and/or differentiation of naive, unprimed T cells or their precursors, which might have a possible functional relevance for primary immune responses following splenectomy.

Prevention and management of overwhelming postsplenectomy infection--an update

OBJECTIVES

To review the diagnosis and management of overwhelming postsplenectomy infection and to discuss various preventative measures.

DATA SOURCES

Data used to prepare this article were drawn from published articles and work in progress.

STUDY SELECTION

Articles were selected for relevance to the subject after location by a MEDLINE key word search.

DATA EXTRACTION

The literature was reviewed to summarize the etiology and pathophysiology of postsplenectomy sepsis. Preventative strategies were outlined with a particular emphasis on education, immunoprophylaxis, and chemoprophylaxis.

DATA SYNTHESIS

Although physicians have become increasingly aware of overwhelming postsplenectomy infection in children, many remain unaware of the risk to asplenic or hyposplenic adults who may have no underlying medical problems. Recent studies have shown that many patients who have had splenectomies have had neither appropriate vaccinations nor teaching that would explain the lifelong nature of their risk. The increasing incidence of penicillin-resistant pneumococci represents a major area of therapeutic and prophylactic concern. The identification of Howell-Jolly bodies on a peripheral blood smear should alert physicians to the need for follow-up to document possible hyposplenism. Attention has focused on a three-pronged attack to this problem, including education, immunoprophylaxis, and chemoprophylaxis.

CONCLUSIONS

Overwhelming postsplenectomy infection should be largely preventable if appropriate precautions are taken. Physicians need to know of the spectrum of diseases associated with hyposplenism and how patients noted to have Howell-Jolly bodies should be investigated. They should also be aware of appropriate guidelines for management of patients with asplenia or hyposplenism.

Laparotomy versus no laparotomy in the management of early-stage, favorable-prognosis Hodgkin's disease: a decision analysis

PURPOSE

To perform a decision analysis that compared the life expectancy and quality-adjusted life expectancy of early-stage, favorable-prognosis Hodgkin's disease (HD) managed with and without staging laparotomy, incorporating data on treatment outcomes of HD in the modern era.

METHODS

We constructed a decision-analytic model to compare laparotomy versus no laparotomy staging for a hypothetical cohort of 25-year-old patients with clinical stages I and II, favorable-prognosis HD. Markov models were used to simulate the lifetime clinical course of patients, whose prognosis depended on the true pathologic stage and initial treatment. The baseline probability estimates used in the model were derived from results of published studies. Quality-of-life adjustments for procedures and treatments, as well as the various long-term health states, were incorporated.

RESULTS

The life expectancy was 36.67 years for the laparotomy strategy and 35.92 years for no laparotomy, yielding a net expected benefit of 0.75 years for laparotomy staging. The corresponding quality-adjusted life expectancies for the two strategies were 35.97 and 35.38 quality-adjusted life years (QALYs), respectively, resulting in a net expected benefit of laparotomy staging of 0.59 QALYs. Sensitivity analysis showed that the decision of laparotomy versus no laparotomy was most heavily influenced by the quality-of-life weight assigned to the postlaparotomy state.

CONCLUSION

Our model predicted that on average, for a 25-year-old patient, proceeding with staging laparotomy resulted in a gain in life expectancy of 9 months, or 7 quality-adjusted months. These results suggest that a role remains for surgical staging in the management of early-stage HD.

Risk of acute myelogenous leukaemia and myelodysplasia following cancer treatment

Now that a substantial group of cancer patients has such a favourable prognosis, it has become increasingly important to evaluate the long-term complications of treatment. Of all late effects of treatment, secondary leukaemia is one of the most serious. Increased risk of AML has been observed both after RT and after CT; however, several types of CT have much stronger leukaemogenic properties than RT. Limited field radiation in the therapeutic dose range is associated with very little or no increased risk of leukaemia, which has been attributed to cell killing at the higher radiation doses. With respect to CT, two different syndromes of treatment-related AML have been recognized. Risk of alkylating agent-related AML is highest in the 5-10 year follow-up period and seems to decrease afterwards. This type of leukaemia is often preceded by MDS, and is characterized by deletions of chromosomes 5 and 7. Leukaemias related to treatment with the topoisomerase II inhibitors are characterized by a short induction period, presentation as myelomonocytic or monocytic leukaemia (rather than MDS) and balanced chromosomal translocations involving bands 11q23 and 21q22. This review addresses the risk of secondary AML and MDS following treatment of HD, NHL, testicular cancer, ovarian cancer, breast cancer and paediatric malignancies. In patients with HD, the risk of AML is higher with an increasing number of mechlorethamine-procarbazine-containing cycles, a greater number of CT episodes, and after splenectomy. The majority of data shows that RT does not add to the leukaemia risk from CT, but this issue is still surrounded by some controversy. ABV(D)-treated patients have a very low risk of AML. Generally, patients with NHL, testicular cancer and breast cancer experience much lower risk of AML than patients with HD. NHL and breast cancer treatment regimens with cumulative cyclophosphamide doses of 20 g or less do not confer an appreciable increase of AML. Recently, strongly increased AML risk has been observed following autologous bone marrow transplantation and other dose intensification strategies. Risk factors for this excess remain to be defined. PVB treatment for testicular cancer is not followed by increased leukaemia risk, but modern etoposide-containing regimens do confer excess risk, of which the magnitude at conventional drug doses is not yet well known. High risk of leukaemia has been reported in children treated with epipodophyllotoxins. The leukaemogenic hazards of cancer treatment should be weighed against their therapeutic benefits.

Partial splenectomy in children: an alternative for splenectomy in the pathological staging of Hodgkin's disease

BACKGROUND

The more accurate staging of Hodgkin's disease in children is achieved with a staging laparotomy and splenectomy. A disadvantage of the splenectomy is the high risk for an overwhelming postsplenectomy sepsis (OPSI). Therefore, the partial splenectomy was introduced as an alternative to splenectomy in the staging of Hodgkin's diseases in children.

METHODS

During the period 1982-1988, 12 children with Hodgkin's disease underwent a staging laparotomy with partial splenectomy. All patients were preoperatively vaccinated with Pneumococcus vaccine. The first three patients received 44 Gy locoregional radiotherapy, whereas nine patients received 25 Gy locoregional radiotherapy and two courses of MOPP/ABVD (mitoxin, oncovin [vincristine], procarbazine, prednisone/adriamycin, bleomycin, vinblastine, decarbazine).

RESULTS

The morbidity was negligible. The pathological stage changed in three patients (25%). During a median follow-up of 6 years (range 4-10), no OPSI was diagnosed. One patient developed a secondary leukaemia.

CONCLUSIONS

Staging laparotomy for Hodgkin's disease is being performed with less frequency because the majority of patients are treated with chemotherapy and low-dose radiation therapy. After splenectomy and chemotherapy regimens with alkylating agents, there is an increased risk for secondary acute leukemia. With partial splenectomy an adequate staging of the disease can be achieved, allowing a more tailored therapy so that systemic chemotherapy will not be used as frequently, resulting in a lower treatment morbidity without decreasing survival.

Second cancer after the treatment for Hodgkin's disease: a report from the International Database on Hodgkin's Disease

Twenty institutions/cooperative groups tabulated second cancers among 12,411 patients diagnosed with Hodgkin's disease between 1960 and 1987, giving 82,850 person-years of observation. Overall, 631 second cancers were observed, as compared with 223.25 expected (observed (O) to expected (E) ratio 2.83, p < 0.001) at least one year after the diagnosis of Hodgkin's disease. Second cancers were acute leukaemias (AL) in 158 cases as compared with 5.75 expected (O/E = 27.48, p < 0.001), non-Hodgkin's lymphomas (NHL) in 106 cases as compared with 3.34 expected (O/E = 31.77, p < 0.001), and solid tumors (ST) in 367 cases as compared with 214.16 expected (O/E = 1.71, p < 0.001), with no differences between males and females. Excess of ST was observed for the following anatomic sites: salivary gland, small intestine, colon, bronchus, pleura, bone, skin other than melanoma and thyroid in males; salivary gland, bronchus, pleura, skin other than melanoma and breast in females. While the excess of second AL and NHL was significant over the 1-14 year period after the start of initial therapy, that of second ST became apparent after the fifth year, increasing with time. Overall, the 15-year cumulative incidence rate of second cancer was 11.2%. It was 2.2%, 1.8% and 7.5% for second AL, NHL and ST, respectively. While the cumulative incidence of AL and NHL plateaued after 17 years, that of ST was still increasing. To analyse whether a particular treatment category was associated with an increased risk of second cancer, a prognostic study was performed on the 11,241 patients who achieved a complete remission and were continuously disease-free. Overall, 87 patients developed an AL, 68 a NHL, and 231 a ST. Combined modality treatments including MOPP or MOPP-like chemotherapy were associated with the higher risk of second AL (Relative risk (RR) = 17.11; p < 0.001) followed by age above 50 (RR > 4.50; p < 0.001), advanced clinical stage (RR > 2.50; p < 0.001), splenectomy (RR = 1.65; p < 0.05) and MOPP or MOPP-like chemotherapy used alone (RR = 2.20; p < 0.05). Factors associated with an increased risk of second NHL were age above 30 (RR > 3.5; p < 0.001), male gender (RR = 1.82; p < 0.05) and clinical stage III (RR = 1.70; p < 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)

Vacuoles in red cells from splenectomized subjects originate during cell life: association with glycosylated haemoglobin?

Whole blood from splenectomized subjects (n = 8) contained a substantial percentage of vacuolated ('pitted') red cells (34.7 +/- 8.3%), while blood from controls revealed none. The percentage of haemoglobin A1 (HbA1) had increased significantly compared with controls (p less than 0.01). Fractionation on cell density revealed that the number of 'pitted' cells and the HbA1 percentage were associated with increased cell density. Fractionation on cell volume showed that 'pitted' cells are equally distributed in fractions with varying mean cell volume (MCV) and that decreasing MCV was associated with a linear rise of HbA1. It appeared that, shortly after splenectomy (n = 4), 'pits' develop early in cell life and that also older cells, after previous splenic contact, are capable of pit formation. A positive correlation found between the number of 'pitted' cells and the percentage of HbA1 might point to an impaired release of HbA1, manifest in the presence of 'pits'. The increased percentage of HbA1 in whole blood from splenectomized subjects may thus be explained.

Initial chemotherapy and low-dose radiation in limited fields in childhood Hodgkin's disease: results of a joint cooperative study by the French Society of Pediatric Oncology (SFOP) and Hôpital Saint-Louis, Paris

To minimize the drawbacks of treatment we had shown in a previous study that it was possible after chemotherapy to limit the radiation fields to the involved areas only. Pursuing our policy of deescalation, we started in January 1982 a study in 29 French pediatric and hematologic centers, with two aims: (1) To compare the efficacy of 4 cycles of two different chemotherapeutic regimens (4 ABVD vs 2 MOPP + ABVD) in early stages (CSIA and II A) while other stages would receive 6 cycles of the same regimen (3 MOPP + 3 ABVD); (2) To evaluate the efficacy of irradiation given at a low dose (20 Gy) in the patients who had a minimum 70% reduction of the size of their nodes (good responders). From January 1982 to March 1987, 174 patients were entered in this study, of whom 157 completed their treatment program at the time of analysis. On completion of chemotherapy, 94% were considered as good responders and were irradiated to 20 Gy. Only 6 patients received a mediastinal boost (up to 40 Gy). Of the 6% (10/157) poor responders a complete remission was obtained in 6 after 40 Gy. Among the good responders, 5 patients relapsed, with only 3 within an area irradiated to 20 Gy. So that 4 nodal relapses occurred among 364 involved lymph areas. The actuarial survival at 42 months (median 30 months) is 95% (IA + IIA = 100%, IB + IIB + III = 94% and IV = 80%) and the disease-free survival 88% (respectively 94, 93 and 54). Until now there is no statistically significant difference between the 2 randomized arms. This study shows that it is possible to achieve a durable remission in most children treated with a less toxic protocol eliminating or reducing Nitrogen Mustard and reducing the dose of irradiation. Less late complications and sequelae are expected with a longer follow-up.

Red cell vacuoles: their size and distribution under normal conditions and after splenectomy

The frequency of occurrence of vacuoles in red blood cells was studied by transmission electron microscopy. Small vacuoles were found in about 13% of the cell sections, and they had a mean diameter of 130 +/- 72 nm (mean +/- SD). It can be estimated that there were about 20 small vacuoles per erythrocyte. The frequency of vacuoles was similar in density-separated cell fractions. In splenectomized patients, the small vacuoles were 4 times more frequent; there was again no difference in vacuole density between top and bottom fractions of density-separated red blood cells. The bottom fraction of red blood cells from splenectomized patients, however, had a high incidence of large vacuoles (greater than 300 nm in diameter) and clustering of small vacuoles. These large vacuoles were probably the result of aggregation and fusion of small vacuoles, and their size allowed detection by light microscopy. Hence, the well-known "pocked" or "pitted" red blood cells of splenectomized individuals were more frequent in the bottom fraction. We conclude that small vacuoles occur normally in erythrocytes, that they tend to cluster and fuse during cell aging, and that the spleen is capable of removing these structures when they reach a certain size.

Splenic function: physiology and splenic hypofunction

A wide variety of disorders can result in diminished splenic function. The pathophysiology appears to be clearly defined in some instances, such as congenital asplenia and disorders of splenic vascular obstruction or congestion. In others, such as the autoimmune and GI disorders, the mechanism remains poorly defined. Further research is needed. The hyposplenia which occurs in many of these disorders has been associated with an increased risk of life-threatening, overwhelming bacterial sepsis. In other instances, this complication has not been reported. This certainly should not be interpreted to mean that it cannot occur. The risk of septicemia in hyposplenic disorders is rarely above 10 to 15%. In disorders with minimal inhibition of splenic function, the incidence of sepsis would presumably be less than the 1.5% incidence following surgical splenectomy for trauma. Considering these data, a very large number of patients would have to become asplenic before it would be likely that one would develop sepsis. Furthermore, the lack of awareness of the possibility of hyposplenia-related sepsis in many of these disorders may cause such occurrences to go unrecognized. Finally, since the risk of sepsis is probably less in hyposplenic adults as compared to children, studies on adults may underestimate the incidence of this complication in children. Many of the disorders reported to cause hyposplenia in adults have not been noted to do so in children. In instances such as celiac disease, it may take many years for the complication to manifest so that it would be unlikely for a child to manifest hyposplenia during childhood. However, in other instances, not enough children have been studied to be confident that the hyposplenia and its associated risk of sepsis are not complications that occur in children. Hyposplenia-related bacterial septicemia is a catastrophic complication. If a patient develops a disorder that is potentially associated with hyposplenia, the patient should be observed for signs of asplenia in the peripheral blood. If the technique is available, quantitation of red cell pits should be performed. If not, other studies of splenic function such as radionuclide scans should be considered, depending on the incidence of hyposplenia in that particular disorder. If evidence of asplenia develops, pneumococcal vaccine should be administered, penicillin prophylaxis should be considered, significant febrile episodes should be managed aggressively, and probably most importantly, the patient and family should be carefully educated about this complication. Most deaths from hyposplenia-related septicemia are preventable.

The effect of abdominal radiation on spleen function: a study in children with Wilms' tumor

Reports of splenic dysfunction in patients with Hodgkin's disease who received radiation therapy to the spleen raise questions concerning impairment of splenic function and the long-term risk of bacterial sepsis in children who receive abdominal radiation for other diseases. Splenic function was studied in 20 children with Wilms' tumor using a quantitative assessment of vacuolated ("pitted") red cells as a measure of reticuloendothelial function. Fourteen children had received abdominal radiation to a field involving the spleen at a median dose of 2000 rads. Their pitted red cells counts were no different from those of 6 children who received therapy without radiation to the spleen or to those of a group of normal children and adults. We conclude that there is no demonstrable long-term impairment of spleen function with radiation doses at or below 2200 rads.

Aspects of splenic hypofunction in old age

The weight of the human spleen decreases in old age. The percentage of erythrocytes with pits observed by interference contrast microscopy was significantly higher in 39 elderly subjects (median 4.2%, range 1.2%-14.6%) than in 34 younger controls (median 1.4%, range 0.6%-6.2%). Further evidence of splenic hypofunction was obtained from 7 elderly people with increased pit counts: the removal from circulation and accumulation into the spleen of heat-damaged autologous erythrocytes was abnormally slow. However, no difference in the spleen area of the same subjects measured by scintillation scanning was observed in comparison with normals. Thus, the weight reduction of spleen in old age is accompanied by a decrease in splenic function.

Postsplenectomy sepsis syndrome. How to identify and manage patients at risk

Established postsplenectomy sepsis syndrome, although infrequent, may carry a mortality rate of over 90%. Pneumococcus (Streptococcus pneumoniae) has been the infective organism in more than 50% of published cases. Certain groups, such as infants, patients with hematologic malignancy, and those with compromised humoral immunity, may be especially susceptible. However, even healthy individuals who have been splenectomized because of trauma may be affected. Within the general population there is a significant pool of asplenic or functionally hyposplenic patients who are not aware of their condition. Efforts must be made to identify any such individual at risk for the postsplenectomy sepsis syndrome. The new 23-valent polysaccharide pneumococcal vaccine should be made available to any asplenic or functionally hyposplenic individual. A high index of suspicion must be maintained for febrile illness in asplenic patients, and if such an illness occurs, a vigorous investigation is mandatory.

Splenic reticuloendothelial function in children with cancer

We studied splenic function in children with cancer by quantitation of pitted, or pocked, erythrocytes (pocked RBC count), that is, the percentage of erythrocytes containing one or more membrane-bound vesicles, as determined by phase interference microscopy. The mean pocked RBC count in 93 normal children and adults was 0.49% (range 0% to 2.0%), with only 2.4% of normal subjects having values greater than 1.5%. Mean pocked RBC count in 28 children after splenectomy was 37% (range 3.2% to 81%). Among 181 children with cancer (525 specimens), the mean pocked RBC count was 1.06% (range 0% to 12.6%). Fifty-nine (32%) patients had one or more values greater than 1.5%, and 25 (13.8%) children had measurements greater than 3.0%, a level previously suggested to have clinical significance. Elevated pocked RBC counts (greater than 1.5%) occurred in more than one third of children with Wilms tumor and acute lymphoblastic leukemia, and in both patients with juvenile chronic myelogenous leukemia. Elevations in pocked RBC counts were not related to specific chemotherapy regimens or to disease activity. Mild splenic reticuloendothelial hypofunction occurs in many children with cancer and may contribute to the risk of infection in these patients.

The evolution and summary results of the Stanford randomized clinical trials of the management of Hodgkin's disease: 1962-1984

This is a summary report of the Stanford randomized clinical trials of the management of Hodgkin's disease, initiated in 1962. There have been four major changes in the treatment protocols during this 22 year period. Between 1962-67, 132 patients with CS I, II and III disease were enrolled on various radiation trials. Between 1968-74, 367 patients were enrolled on studies primarily evaluating the role of adjuvant MOPP chemotherapy. Between 1974-80, variations in the chemotherapy regimen and the sequences of the combined modality programs were studied. The current studies, initiated in 1980, have enrolled 102 patients, and test a new mild adjuvant chemotherapy, VBM, (vinblastine, bleomycin and methotrexate) and utilizes ABVD in combined modality and alternating regimens. During the two decades of these studies, involving more than 800 patients, the initial remission rate and duration and the survival of all patients treated have progressively improved.

Selective hemisplenectomy for Hodgkin's disease

Schellong's recommendation to do a selective splenectomy in Hodgkin's disease supported by our retrospective histological findings in biopsies of lymph nodes and spleens of 25 patients. In addition, we recommend a hemisplenectomy instead of a splenectomy in cases of involvement of the lymph nodes at the pancreatic tail and at the hilus of the spleen. Hemisplenectomy, which is not a more difficult or more time-consuming operation, provides more security in judging an invasion of the spleen.

Return of splenic function after splenectomy: how much tissue is needed?

Ninety patients whose spleen had been removed either because of trauma (41 cases) or as an elective procedure (49) were investigated for return of splenic function by counting pitted red cells and examining spleen scans made after injection of heat damaged 99mTc labelled red cells. There was no significant difference in the proportion of pitted red cells between the two groups of patients. Evidence of splenic tissue in scintiscans was not invariably associated with low pitted red cell values, suggesting that the presence of splenic tissue did not necessarily mean return of splenic function. In every patient whose proportion of pitted red cells was less than 16.2% the scintiscan showed splenic uptake. The proportion of patients with pitted red cell values below 16.2% was significantly higher in the group operated on for trauma, and it is concluded that this was due to splenosis. A high inverse correlation between pitted red cell counts and computed splenic volumes was found. Patients with pitted red cell values of less than 16.2% had computed volumes of 22-133 cm3; below this range the proportion of pitted red cells rose very sharply. These results confirm that splenosis occurs in adults, though less often than in children, and suggest that when splenic tissue is to be implanted a graft of at least 20-30 cm3 is needed to ensure satisfactory return of splenic function.

'Pitted' erythrocytes: impaired formation in splenectomized subjects with congenital spherocytosis

'Pitted' erythrocyte counts are widely used in the quantitative assessment of functional hyposplenism and in the prediction of recurrence of splenic function in splenectomized subjects. Both of these functions require counts from electively splenectomized controls for comparison. The 'pitted' erythrocyte counts in patients splenectomized for congenital spherocytosis are lower than those found in subjects whose spleens were removed electively for other reasons. This appears to be due to the specific membrane defect which impairs the formation of the vacuoles which are responsible for the appearance of 'pitted' erythrocytes under the interference-phase microscope.

Overwhelming post-splenectomy infection in Hodgkin's disease: pathogenesis and prevention

After staging splenectomy, the risk of overwhelming sepsis in patients with Hodgkin's disease reaches 21% in certain subgroups. Youth, recent splenectomy and vigorous chemoradiotherapy predispose patients to this complication. Because of its explosive course and its known microbiology, post-splenectomy sepsis is better suited to prevention than to treatment. Since immunisation prior to treatment produces good antibody responses, all patients with Hodgkin's disease should probably be vaccinated against encapsulated bacteria at least 10 days prior to the onset of therapy.