Intralesional immunotherapy of melanoma with BCG

Pathogenic mechanisms and etiologic aspects of Mycobacterium avium subspecies paratuberculosis as an infectious cause of cutaneous melanoma

Infectious etiologies have previously been proposed as causes of both melanoma and non-melanoma skin cancer. This exploratory overview explains and presents the evidence for the hypothesis that a microorganism excreted in infected ruminant animal feces, Mycobacterium avium subspecies paratuberculosis (MAP), is the cause of some cases of cutaneous melanoma (CM). Occupational, residential, and recreational contact with MAP-contaminated feces, soil, sand, and natural bodies of water may confer a higher rate of CM. Included in our hypothesis are possible reasons for the differing rates and locations of CM in persons with white versus nonwhite skin, why CM develops underneath nails and in vulvar skin, why canine melanoma is an excellent model for human melanoma, and why the Bacille Calmette-Guérin (BCG) vaccine has demonstrated efficacy in the prevention and treatment of CM. The pathogenic mechanisms and etiologic aspects of MAP, as a transmittable agent underlying CM risk, are carefully deliberated in this paper. Imbalances in gut and skin bacteria, genetic risk factors, and vaccine prevention/therapy are also discussed, while acknowledging that the evidence for a causal association between MAP exposure and CM remains circumstantial.

Imiquimod as Local Immunotherapy in the Management of Premalignant Cutaneous Conditions and Skin Cancer

Cutaneous cancers are, by far, the most common malignant neoplasms of the human being. Due to the great array of clinical conditions, their worldwide increasing incidence and the steady ageing of the population, non-invasive treatments modalities that show a good clinical response, a proper benefit-risk ratio and cosmetic results are becoming increasingly important in the clinical setting. Imiquimod is a topically applied immunomodulator which is often used in the management of several premalignant and malignant cutaneous disorders. This article is a review of the current literature on its mechanism of action, pharmacokinetics, and therapeutical effects.

Activated melanoma vessels: A sticky point for successful immunotherapy

Metastatic melanoma is a devastating disease with a marginal-albeit increasing-hope for cure. Melanoma has a high mutation rate which correlates to the expression of numerous neo-antigens and thus is associated with the potential to induce and strengthen effective antitumoral immunity. However, the incomplete and potentially insufficient response to established immunotherapies (response rates usually do not markedly exceed 60%) already points to the need of further studies to improve treatment strategies. Multiple tumor escape mechanisms that allow melanoma to evade from antitumoral immune responses have been characterized and must be overcome to achieve a better clinical efficacy of immunotherapies. Recently, promising progress has been made in targeting tumor vasculature to control and increase the infiltration of tumors with effector lymphocytes. It has been hypothesized that amplified lymphocytic infiltrates in melanoma metastases result in a switch of the tumor microenvironment from a non-inflammatory to an inflammatory state. In this view point essay, we discuss the requirements for successful homing of lymphocytes to melanoma tissue and we present a mouse melanoma xenograft model that allows the investigation of human tumor vessels in vivo. Furthermore, current clinical studies dealing with the activation of melanoma vasculature for enhanced effectiveness of immunotherapy protocols are presented and open questions for routine clinical application are addressed.

Proposing BCG Vaccination for Mycobacterium avium ss. paratuberculosis (MAP) Associated Autoimmune Diseases

Bacille Calmette-Guerin (BCG) vaccination is widely practiced around the world to protect against the mycobacterial infection tuberculosis. BCG is also effective against the pathogenic mycobacteria that cause leprosy and Buruli's ulcer. BCG is part of the standard of care for bladder cancer where, when given as an intravesicular irrigant, BCG acts as an immunomodulating agent and lessens the risk of recurrence. Mycobacterium avium ss. paratuberculosis (MAP) causes a fatal enteritis of ruminant animals and is the putative cause of Crohn's disease of humans. MAP has been associated with an increasingly long list of inflammatory/autoimmune diseases: Crohn's, sarcoidosis, Blau syndrome, Hashimoto's thyroiditis, autoimmune diabetes (T1D), multiple sclerosis (MS), rheumatoid arthritis, lupus and Parkinson's disease. Epidemiologic evidence points to BCG providing a "heterologous" protective effect on assorted autoimmune diseases; studies using BCG vaccination for T1D and MS have shown benefit in these diseases. This article proposes that the positive response to BCG in T1D and MS is due to a mitigating action of BCG upon MAP. Other autoimmune diseases, having a concomitant genetic risk for mycobacterial infection as well as cross-reacting antibodies against mycobacterial heat shock protein 65 (HSP65), could reasonably be considered to respond to BCG vaccination. The rare autoimmune disease, relapsing polychondritis, is one such disease and is offered as an example. Recent studies suggesting a protective role for BCG in Alzheimer's disease are also explored. BCG-induced energy shift from oxidative phosphorylation to aerobic glycolysis provides the immunomodulating boost to the immune response and also mitigates mycobacterial infection-this cellular mechanism unifies the impact of BCG on the disparate diseases of this article.

Smallpox and BCG vaccination in childhood and cutaneous malignant melanoma in Danish adults followed from 18 to 49 years

BACKGROUND

Early smallpox and Bacillus Calmette-Guérin (BCG) vaccinations have been associated with reduced risk of cutaneous malignant melanoma (CMM). We assessed the association between pre-school smallpox vaccination and early-school BCG vaccination and CMM in a young Danish population.

METHODS

We conducted a register-based case-cohort study of individuals growing up during the phase-out period of smallpox and BCG vaccination in Denmark (born 1965-1976) utilising the decrease in vaccination during this period. Information on childhood vaccinations and potential confounders from Copenhagen school health records were linked with nationwide registers on cancer (CMM diagnoses), migrations and deaths by personal identification numbers.

RESULTS

The individuals were followed from age 18 until 31/12/2014 (maximum age at end of follow-up, 49 years). 188 cases of CMM occurred in the background population of 46,239 individuals; 172 CMM cases (91%) had full information and were analysed. The adjusted hazard ratio (HR) for CMM by BCG and/or smallpox vaccination compared with neither vaccine was 1.29 (95% confidence interval (CI) 0.72-2.31). For smallpox vaccination only, HR = 1.23 (95% CI 0.53-2.86) for BCG vaccination only, HR = 1.13 (95% CI 0.61-2.09) and for both smallpox and BCG vaccination, HR = 1.75 (95% CI 0.87-3.48) compared with none of these. Vaccination below the age of one year gave similar results.

CONCLUSIONS

We found no strong beneficial effect of smallpox and BCG vaccination against CMM among young adult Danes and with broad confidence intervals our data alone could be compatible with both modest preventive effects, no effects, and modest harmful effects. Our estimates do not contradict a potential modest beneficial effect of neonatal vaccination.

Diagnosis and treatment of in-transit melanoma metastases

In transit metastases (ITM) from extremity or trunk melanomas are subcutaneous or cutaneous lymphatic deposits of melanoma cells, distant from the primary site but not reaching the draining nodal basin. Superficial ITM metastases develop in 5-10% of melanoma patients and are thought to be caused by cells spreading along lymphatics; ITM appear biologically different from distant cutaneous metastases, these probably due to a haematogenous dissemination. The diagnosis is usually clinical and by patients, but patients need to be adequately educated in the recognition of this clinical situation. Ultrasound or more sophisticated instrumental devices may be required if the disease develops more deeply in the soft tissues. According to AJCC 2009 staging classification, ITM are included in stages IIIb and IIIc, which are considered local advanced disease with quite poor 5-year survival rates and outcomes of 24-54% at 5 years.² Loco-regional recurrence is in fact an important risk factor for distant metastatic disease, either synchronous or metachronous. Therapy for this pattern of recurrence is less standardised then in most other clinical situations and options vary based on the volume and site of the disease. Definitive surgical resection remains the preferred therapeutic approach. However, when surgery cannot be performed with a reasonable cosmetic and functional outcome, other options must be utilized.^3-6 Treatment options are classified as local, regional or systemic. The choice of therapy depends on the number of lesions, their anatomic location, whether or not these are dermal or subcutaneous, the size and the presence or absence of extra-regional disease.

Intralesional Immunotherapy for Metastatic Melanoma: The Oldest and Newest Treatment in Oncology

The last few years have yielded exciting developments in immunotherapy for cancer. The promise of cancer immunotherapy has been well known for many years, but had generally produced limited or inconsistent benefit to patients. Intralesional therapies, which are in fact one of the oldest forms of immunotherapy, are also demonstrating benefits in the modern age. This review discusses the origins of intralesional immunotherapy and its underlying rationale. It also discusses the reemergence of this mode of therapy into the modern era, which is where Donald L. Morton, subject of this edition of the journal, plays a major role. The review also discusses current areas of investigation. Given the intuitive advantages of this strategy and the demonstrated, expanding areas of clinical responses, it is likely that intralesional immunotherapy will remain a useful component of cancer treatment into the future.

Is sentinel node susceptibility to metastases related to nodal immune modulation?

Sentinel lymph nodes (SLNs), the initial site of regional metastases, directly receive lymph containing immune-modulatory cytokines and tumor cells from primary melanomas. Immune-suppressed SLNs are ideal for studies of tissue susceptibility to metastases. They show reduced antigen-presenting dendritic cells, activated T cells, high endothelial venules, and transvenular immigration of T cells. Tumor-induced immune suppression contributes to establishment of nodal metastases. SLNs may serve as an effective model to study reversal of tumor-induced immune suppression. We reviewed this topic in Nature Reviews of Immunology in 2006. We here summarize the Nature paper and provide additional results from ongoing studies and the recent literature.

Intralesional therapy for in-transit and satellite metastases in melanoma

Intratumoral therapy with bacteria/bacterial products dates to at least the 1890s. Over the decades this has expanded beyond the use of microbes and microbial products to include chemicals, cancer chemotherapeutic agents, cytokines, recombinant organisms, and hybrid molecules. The appeal of this method of delivery is the ability to deliver high concentrations of the therapeutic agent directly to the tumor, often with minimal side effects. This article summarizes the use and efficacy of the various agents used in the past and present in the treatment of in-transit and satellite metastases in melanoma.

Evolving role of tumor antigens for future melanoma therapies

ABSTRACT: 

Human tumor rejection antigens recognized by T lymphocytes were first defined in the early 1990s and the identification of shared tumor-restricted antigens sparked hopes for the development of a therapeutic vaccination to treat cancer, including melanoma. Despite decades of intense preclinical and clinical research, the success of anticancer vaccines based on these antigens has been limited. While melanoma is a highly immunogenic tumor, the ability to prime immunity with vaccines has not generally translated into objective disease regression. However, with the development of small molecules targeting oncogenic proteins, such as V600-mutated BRAF, and immune checkpoint inhibitors with demonstrable long-lasting clinical benefit, new opportunities for antigen-targeted directed therapies are emerging.

Intralesional injection of rose bengal induces a systemic tumor-specific immune response in murine models of melanoma and breast cancer

Intralesional (IL) injection of PV-10 has shown to induce regression of both injected and non-injected lesions in patients with melanoma. To determine an underlying immune mechanism, the murine B16 melanoma model and the MT-901 breast cancer model were utilized. In BALB/c mice bearing MT-901 breast cancer, injection of PV-10 led to regression of injected and untreated contralateral subcutaneous lesions. In a murine model of melanoma, B16 cells were injected into C57BL/6 mice to establish one subcutaneous tumor and multiple lung lesions. Treatment of the subcutaneous lesion with a single injection of IL PV-10 led to regression of the injected lesion as well as the distant B16 melanoma lung metastases. Anti-tumor immune responses were measured in splenocytes collected from mice treated with IL PBS or PV-10. Splenocytes isolated from tumor bearing mice treated with IL PV-10 demonstrated enhanced tumor-specific IFN-gamma production compared to splenocytes from PBS-treated mice in both models. In addition, a significant increase in lysis of B16 cells by T cells isolated after PV-10 treatment was observed. Transfer of T cells isolated from tumor-bearing mice treated with IL PV-10 led to tumor regression in mice bearing B16 melanoma. These studies establish that IL PV-10 therapy induces tumor-specific T cell-mediated immunity in multiple histologic subtypes and support the concept of combining IL PV10 with immunotherapy for advanced malignancies.

Role of bacillus Calmette-Guérin in the treatment of advanced melanoma

Early trials of Bacillus Calmette-Guérin (BCG)-based immunotherapy for melanoma consistently show a trend toward improved clinical outcomes in patients treated with BCG compared with observation alone. As an extension of these findings, investigators have initiated the Malignant Melanoma Active Immunotherapy (MMAIT) trials in patients with stage III (MMAIT-III) and stage IV (MMAIT-IV) disease. The overall survival of the patients receiving BCG plus placebo was much better than expected in both studies, thus suggesting a potential for BCG as an adjuvant after the resection of advanced disease. The work contained herein will explore the clinical rationale for adjuvant BCG in future trials focused on the treatment of patients with advanced malignant melanoma.

Immunotherapy for malignant melanoma--tracing Ariadne's thread through the labyrinth

A working group (FEBIM) within the European Organisation for Research and Treatment of Cancer undertook extensive studies on the possible association of infectious diseases and the risk of malignant melanoma. These studies provided evidence that several infectious diseases and also some vaccines including the anti-tuberculosis vaccine, BCG, derived from Mycobacterium bovis, confer a significant level of protection against this form of cancer. In recent years, the importance of immunoregulatory networks in the establishment of tolerance to tumour antigens and the key role of the innate immune system in the development of such networks have been recognised. The molecular patterns of micro-organisms activate pattern recognition receptors on antigen presenting cells and determine the qualitative nature of the ensuing immune response. Bacteria in the actinomycetales family, notably members of the genus Mycobacterium, exhibit particularly powerful adjuvant activity and profoundly affect underlying patterns of immune reactivity. In particular, there is growing evidence that a heat-killed preparation of a strain of Mycobacterium vaccae is able to down-regulate patterns of immune reactivity that favour the tumour and to induce those that lead to anti-cancer immune responses. The results of preliminary clinical observations with melanoma patients, and published studies on other cancers, point to the need for more formal clinical trials.

Phase I/II study of topical imiquimod and intralesional interleukin-2 in the treatment of accessible metastases in malignant melanoma

BACKGROUND

Patients with metastatic skin disease in malignant melanoma can be difficult to treat effectively, often requiring repeated treatments with different modalities in an attempt to control their disease. Treatment of nonsurgically resectable melanoma deposits is unsatisfactory, as they are often multiple and recurring. Anecdotal evidence from individual use of imiquimod in superficial metastases and intralesional interleukin (IL)-2 in subcutaneous deposits suggests that the combination may be more effective in bulky subcutaneous disease.

OBJECTIVES

To investigate the combination of topical imiquimod and, for selected lesions, intralesional IL-2, to treat a small cohort of patients with accessible melanoma metastases resistant to other treatments.

METHODS

Thirteen patients were recruited: all had evidence of multiple cutaneous and/or subcutaneous metastases. Imiquimod was applied to the metastases on a daily basis for 4 weeks, before the introduction of intralesional IL-2. This was injected up to three times a week, into selected lesions, with 0.1 mL injected per lesion at a concentration of 3.6 MIU mL(-1), a total of 1 mL being given at each session. The treated lesions were assessed individually at intervals of 3 months.

RESULTS

Thirteen patients were treated, with 10 being eligible for assessment. In total, 182 lesions were treated: 137 purely cutaneous lesions and 41 subcutaneous lesions. Overall, a clinical response was seen in 92 lesions (50.5%) with 74 (40.7%) of these being a complete response (CR) with 91% of the CRs being in the cutaneous lesions. New lesions did appear during the treatment course; however, patients with cutaneous disease experienced a marked slowing of the appearance of new cutaneous lesions. No cutaneous lesions that responded reappeared on cessation of treatment.

CONCLUSIONS

The combination of imiquimod and IL-2 is effective in controlling this mixed cutaneous and subcutaneous disease, and is well tolerated. Imiquimod alone is often enough to elicit a response in purely cutaneous lesions. The addition of intralesional IL-2 increases the response rates in subcutaneous lesions, and in otherwise refractory cutaneous lesions.

Tumour-induced immune modulation of sentinel lymph nodes

Sentinel lymph nodes (SLNs), being the first nodes to receive lymph from a primary tumour and the preferential site of initial tumour metastases, are intensively exposed to the bioactive products of tumour cells and other associated cells. This makes them ideal for studies of the factors that determine selective tissue susceptibility to metastases. We postulate that tumour-induced immune modulation of SLNs facilitates lymph-node metastases by inhibiting the generation of tumour-specific cytotoxic T cells that are active against tumour cells of primary and metastatic melanomas. Immune modulation of the lymph nodes can be reversed by granulocyte/macrophage colony-stimulating factor (GM-CSF), a finding that has implications for the future therapy of lymph-node metastases.

Experimental frontiers for clinical applications: Novel approaches to understanding mechanisms of lymph Node metastases in melanoma

Sentinel lymph nodes are the first nodes to receive lymph from primary tumors and are the preferential site of initial metastases. Sentinel nodes show morphology changes that suggests immune modulation with reduced antigen-presenting dendritic cells, activated T lymphocytes, high endothelial venules and transvenular migration of T lymphocytes. Tumor cells generate down-regulatory molecules. We postulate that tumor-induced immune dysfunction facilitates establishment of nodal metastases. Nodal immune modulation can be reversed by granulocyte macrophage colony-stimulating factor (GMCSF), a finding with implications for future therapy to prevent or reverse these nodal metastases.

Evaluation of Immunotherapy in the Treatment of Melanoma

These data show that the extraordinary potency of the immune system can be harnessed to control or destroy melanoma. The proven impact has been limited for patients who have melanoma, but has been dramatic and lasting in selected groups. Recent improvements in understanding of immunology, including mechanisms regulating immune responses and methods of tumor cell escape, are already yielding improved clinical outcomes and potential avenues for extending benefits to more patients. Thus, although the full potential of this treatment modality has yet to be realized, the vanguard of the "treatment of tomorrow" has clearly arrived.

Immunological aspects of head and neck cancer: biology, pathophysiology and therapeutic mechanisms

Advanced cancer and head and neck cancer, in particular, remains a major clinical challenge with its associated morbidity and inevitable mortality. Local control of early disease is achievable in many solid tumours with current surgical and radiotherapeutic techniques but metastatic disease is associated with poor outcome and prognosis. It is known that, by the time of presentation, many patients will already have occult microscopic metastatic disease, and surgery and radiotherapy will not result in long-term survival. What little effect modern chemotherapeutic agents have on microscopic disease is, however, limited by systemic toxicity and multi-drug resistance. Immune surveillance is postulated to be operative in man. There is evidence, however, that patients with progressive tumour growth have failure of host defences both locally and systemically. Various possible defects and tumour escape mechanisms are discussed in the review. Immunotherapy and, in particular adoptive T cell therapy and DC therapy, show promise as putative tumour-specific therapy with clinical benefits. These techniques are undergoing development and evaluation in phase 1 clinical trials. Preliminary data suggest that the treatments are well tolerated. Unfortunately, there is limited evidence of significant and prolonged improvements in clinical outcome. Further developments of beneficial protocols (adjuvants, mode and frequency of vaccination etc) and multicentre studies of the use of immunotherapy in cancer are now required.

Making use of the primary tumour

Surgical resection of a primary tumour is often not sufficient to cure a patient. Even when no residual cancer can be detected at time of surgery, metastases may appear in the following years, which indicates that the primary tumour had apparently spread before surgery. Following surgery, systemic chemotherapy may be used to eradicate micro-metastatic disease. Here we present two unconventional strategies that implement new insights into tumour biology and tumour immunology in the treatment of patients with cancer. Both experimental strategies use the individual characteristics of the patient's primary tumour to optimise the control of life-threatening micro-metastases. We aim to modulate the patient's adaptive immune system, targeting it towards the patient's own tumour cells to eradicate residual disease following local treatment. In one approach, this is done by autologous tumour cell vaccinations as adjuvant treatment for colon cancer patients and, in a second approach, by giving chemo-immunotherapy before local treatment to women with locally advanced breast cancer.

Does bacillus Calmette-Guérin immunotherapy accelerate growth and cause metastatic spread of second primary malignancy?

In our study, 29 of 150 patients with bladder cancer also had other associated primary malignancies, 10 of which were manifested after intravesical treatment with bacillus Calmette-Guérin (BCG). Second primary malignancies developed in 5 of these patients within three months of the start of BCG therapy. All 5 showed acceleration of the second primary tumor, and distant metastatic lesions developed in 4. In the other 5 patients nonbladder primary malignancies developed eight months or more after intravesical BCG therapy started, but did not show acceleration or spread. Twenty patients with other primary malignancies that had developed months to years before intravesical therapy did not show acceleration or spread of those tumors. We have seen enough cases of patients who received intravesical BCG at the time of growth and spread of second primary malignancies to warrant concern. Animal and human studies of BCG use for treatment of malignancy indicate that the temporal relationship between the starting point of tumor development and the starting point of BCG treatment is crucial in determining whether BCG will eradicate or exacerbate the tumor. We have therefore instituted a change in our treatment until the question of whether or not BCG causes the appearance and spread of these second malignancies is answered.

[Intratumor immunotherapy with BCG cell wall preparations: development of a new therapy approach for head-neck tumors]

The present study deals with the influence of intratumoral injections of BCG cell-wall preparations (CWP) on the development of malignant tumors in the head-neck region. Line 10 tumor cells in strain 2 guinea pigs were used in a first assay. It became evident that intratumoral BCG-CWP injection leads to total tumor regression, a situation which can also be achieved by radical surgery. In contrast to the radically operated animals, those injected intratumorally with BCG-CWP develop a tumor-specific immunity. A second animal system was used to examine the effect of intratumoral BCG-CWP treatment on the development of autochthonous squamous cell carcinomas in cows. In this model, radical surgery leads to a clinical cure in all cases, while intratumoral BCG-CWP therapy leads to a complete clinical cure in 50% of the animals (observation period: 1 year). On the basis of experiments performed with animals systems, a clinical study was initiated to examine the effect of preoperative BCG-CWP injection in patients with squamous cell carcinomas in the head-neck region. At present, the case study involves 24 patients. The cumulative percentage of patients in complete tumor remission is now 69% for BCG-CWP pretreated tumor patients and 39% for patients who underwent surgery only. The hitherto existing life-table analyses of both therapy groups and the small degree of side effects resulting from BCG-CWP seem to justify a continuation of the study until a statistically confirmed statement can be made about the curative effect of BCG-CWP within the framework of a combination therapy in patients with squamous cell carcinomas in the head-neck region.

Combined BCG and irradiation treatment of skin metastases originating from malignant melanoma

Treatment with BCG (Bacillus Calmette-Guérin) followed by irradiation was attempted to improve response to therapy by cutaneous metastases from malignant skin melanomas. Both agents were applied in low doses, known to cause minimal side effects. Nineteen patients, divided into three groups, entered the clinical trial. The first group consisted of five patients with relatively large metastases that usually appeared as a residual disease in the surgically treated area. Five patients with numerous, large metastases were included in the third group. The treatment sequence consisted of applying BCG intralesionally in doses from 4 x 10(5) to 1.17 x 10(7) viable units. After a free interval, the affected area was irradiated with doses from 1500--2500 ret. Patients with numerous small metastases and those with a small number of larger metastases, i.e., patients of the first and second group, showed a complete response and in these cases regression affected all the noninjected nodules and was also effective when regression could not have been achieved by BCG alone.

Treatment of disseminated malignant melanoma with high-dose oral BCG

Thirty patients with unresectable disseminated melanoma (Stage IV) were treated with Bacillus Calmette-Guerin (BCG) (Moreau strain--Rio de Janeiro) by mouth, with weekly doses ranging between 200 mg and 28,000 mg. Five patients died in the first two months of treatment. Of the remaining 25 patients, two (8%) showed complete regression, and one (4%) partial regression. Seven patients (28%) had stabilization of the disease for a six-month period, and 15 (60%) had progression of the disease. Complete and partial regressions were seen only in patients with extravisceral (subcutaneous) metastases, and were associated with a longer survival time. Regression of the subcutaneous metastatic nodules was always accompanied by the following local phenomena: increased temperature; local inflammation; softening, pain and pruritus at the nodule site; and a gradual decrease in size. At the site of the tumor mass, a hypochromic halo appeared. This halo remained permanently and was pathognomonic of the metastatic nodule rejection. When the halo was fully established, the inflammatory infiltrate was minimal and the malignant cells disappeared. If the area contained hairs, they underwent complete albinization. Serial biopsies of the nodules undergoing inflammatory changes and decreased consistency exhibited an intense cellular infiltration of lymphocytes, macrophages, and plasma cells around the malignant cells. This sometimes simulated lymphoid follicle formation involving the melanoma cells associated with necrosis in a centripetal way. Some patients with visceral metastases (particularly pulmonary) had an unexpectedly long survival, apparently associated with interruption of the growth rate of the masses. Eleven out of 20 deaths were due to cerebral metastases. When cerebral disease was diagnosed, BCG was discontinued and the administration of corticoids was usually associated with a disappearance of the inflammatory signs at the nodule sites, but with progression of the disease. Toxicity was minimal.

Pott's disease following BCG therapy of melanoma

The first reported case of a patient with BCG-induced Pott's disease following immunotherapy for melanoma is presented. No signs or symptoms of the disease were detected for 2 1/2 years after therapy. The diagnosis and treatment of this complication of melanoma therapy are discussed.

Histopathological modifications following immunotherapy with P 40 in rats bearing DMBA-induced mammary carcinoma

Female Sprague-Dawley rats bearing primarily-induced mammary carcinomas were treated with a new immunostimulating agent (P 40). The histopathological modifications encountered in tumors, lymph nodes, liver and spleen are described. Intratumoral injections provoke a more widespread response of the RES, and particularly a more intense reaction in the draining lymph nodes, than systemic treatment.

Regression of tumors in guinea pigs after treatment with synthetic muramyl dipeptides and trehalose dimycolate

A high incidence of tumor regression was observed in guinea pigs bearing transplantable, line-10 hepatocellular carcinomas when synthetic muramyl dipeptides combined with trehalose dimycolate in oil-in-water emulsions were injected directly into the tumors. These compounds are promising candidates to replace viable bacillus Calmette-Guérin in cancer immunotherapy in humans and animals.

Regression of established oral tumors after intralesional injection of living BCG or BCG cell walls

Oral tumors with associated cervical lymph node metastases developed after injection of tumor cells into buccal pads of inbred guinea pigs. Intralesional injection of living BCG or BCG cell walls (CW) caused regression of established tumors, prevented the development of cervical lymph node metastases and led to the development of host resistance to the growth of subsequent tumor transplant.

Further observations on the inhibition of tumor growth by C. parvum with cyclophosphamide. VII. Effect of treatment prior to primary tumor removal on the growth of distant tumor

The present investigations were directed toward determining whether primary tumor manipulation prior to its removal is advantageous for the control of metastases and survival. Studies were carried out to ascertain whether 1) there is justification for delaying surgical removal of a primary tumor to permit preoperative administration of cyclophosphamide (CY) and/or C. parvum (CP) and 2) there is an advantage to administering the immunotherapy directly into a primary tumor. After operation, in all investigations, systemic CP and CY was used. Despite the putative similarity of animals, tumors and treatment regimens there was marked variation in response of tumors to therapy. No benefit was derived from administering preoperative immunotherapy alone. When operation was delayed to employ systemic immuno-chemotherapy, a slight improvement in the control of distant tumor was noted. The employment of preoperative intratumor immunotherapy led to a greater prolongation of survival and more inhibition of distant tumor growth than did immediate primary tumor removal or the use of preoperative systemic immunotherapy. The results suggest that there may be an advantage to delaying removal of a primary tumor so that it may be employed in therapeutic strategies directed toward control of metastatic disease.

Safety and efficacy of living BCG or BCG cell walls (CW) in the treatment of guinea pig hepatoma

Guinea pigs with established intradermal tumors and microscopic lymph node metastases were treated by intralesional injection of graded doses of living BCG or BCG CW. The lowest dose of living BCG used produced a significant cure rate and no grossly evident toxicity. An intermediate and the highest dose of living BCG used cured some animals but others lost weight and a significant number died as a result of the treatment. Histologic examination of animals with significant weight loss showed fatty degeneration of the liver, granulomatous hepatitis and histiocytic infiltration of the spleen. None of the doses of BCG CW used was toxic and they were at least as effective as living BCG in intralesional treatment. In some experiments in which treatment was delayed it was found that the extent of disease required to render treatment ineffective was about the same for living BCG and for BCG CW.

Adjuvant immunotherapy with BCG in squamous-cell bronchial carcinoma. Immune-reactivity in relation to immunostimulation (preliminary results in a controlled trial)

Jansen, H M, The, T H, de Gast, G C, Esselink, M T, van der Wal, A M, and Orie, N G M (1978).Thorax, 33, 429-438. Adjuvant immunotherapy with BCG in squamous-cell bronchial carcinoma. Immune-reactivity in relation to immunostimulation (preliminary results in a controlled trial). Twenty-nine patients with, at operation, evidence of locally advanced primary squamous-cell bronchial carcinoma (stage II, UICC, Geneva, 1974) had lung resection to remove all the visible tumour. Postoperatively a randomly chosen group of 16 patients received adjuvant BCG immunostimulation by scarifications, while the control group received no adjuvant treatment. Follow-up studies were done from three to 23 months. Immune-reactivity in vivo with PPD and DNCB skin tests, and in vitro with E-rosetting tests and lymphocyte transformation tests with PHA, Con A, diphtheria toxoid, and PPD was monitored in 10 treated and in seven untreated patients. Recurrence rates decreased appreciably in the BCG-stimulated group after a six to 23 months' follow-up (p<0·005). A pronounced increase in both in-vivo and in-vitro immune-reactivity went in parallel with a more favourable clinical outcome in the BCG-treated group. In these cases there was a significant increase in skin reactivity to PPD three months after surgery (p<0·025) and a statistically significant rise in lymphocyte reactivity to Con A (p<0·05), diphtheria toxoid (p<0·01), and PPD (p<0·05) but not to PHA 12 months after surgery. DNCB skin reactivity increased as well in the BCG-treated group, but the number of individuals was too small for statistical evaluation. Increase in immune responsiveness did not occur in the control group and appeared to be independent of the initial immune state of the patients. No differences were found in the numbers of E-rosetting lymphocytes in relation to immunotherapy. It is concluded that adjuvant BCG immunotherapy used in patients with minimal residual bronchial carcinoma improves the prognosis and a favourable clinical outcome is mirrored by an increase in cellular immune reactivity.

Clinical and immunologic studies of disseminated BCG infection

Eight patients with disseminated BCG infection following injection of BCG into primary melanomas have been studied. These patients developed persistent fevers beginning 9 to 20 days following BCG injection. Severe liver function abnormalities occurred in all patients and peaked approximately 20 days following BCG injection. The persistent fevers, and clinical signs and symptoms of disseminated BCG infection lasted from 7 to 22 days before subsiding. Liver function abnormalities sometimes took six months to return to normal. Evidence of granulomas in liver and bone marrow were present. The natural course of this disease did not appear to be affected by therapy with isoniazid (INH). In vitro immunologic studies revealed a severe depression of lymphocyte reactivity in five of six patients sequentially tested. Wide dissemination of BCG from the site of injection is a severe complication of BCG therapy. The clinical course of this disease and suggestions for management are described in this paper.