1/439. Complete remission of a diffuse pontine glioma. A patient is described in whom a large diffuse glioma of the pons extending into the midbrain was diagnosed at the age of 2 years. biopsy showed a fibrillary astrocytoma. After shunting of a hydrocephalus, the clinical symptoms abated without conventional therapy. Repeated MRI studies showed a continuous decrease of the tumour which was no longer visible when the patient was 6.6 years old. In reviews on spontaneous remissions of oncologic disorders we were unable to find a case of a biologically benign brain stem tumour. There is one isolated report on a similar case, though without histologic documentation. ( info) |
| We report a case of a 20-year-old Japanese female with recurrent anaplastic large cell lymphoma (ALCL) associated with sjogren's syndrome (SjS). She was first diagnosed to have ALCL presenting with axillary lymphadenopathy, which within a month underwent spontaneous remission, at the age of 12 years. Eight years later she developed left inguinal lymphadenopathy with clinical overt sicca symptoms associated with elevated serum IgG, interleukin (IL)-1beta and IL-6 levels. Lymph node biopsy was now diagnostic of ALCL characterized by large pleomorphic CD30 blast cells with the specific chromosomal abnormality, t(2;5)(p23;q35). In contrast to this the salivary gland and renal biopsy revealed infiltration of small lymphocytes, morphologically and cytogenetically distinct from the ALCL cells. Interestingly, SjS symptomatology correlated with disease activity of ALCL and based on an association with elevated IgG and IL-6 levels, suggesting that the concurrence of these two diseases could be more than coincidental. To the best of our knowledge, this is the first reported case of ALCL presenting concurrently with SjS. ( info) |
3/439. A natural cytotoxic T cell response in a spontaneously regressing human melanoma targets a neoantigen resulting from a somatic point mutation. We have studied a case of human primary melanoma displaying the classical signs of a spontaneous regression in order to characterize potentially efficient anti-tumor T cell responses. In a previous series of experiments a unique TCR Vbeta16 T cell was shown to be highly expanded at the tumor site. The corresponding clone was isolated in vitro and found to be a CD8 cytotoxic T lymphocyte with a strong and selective cytolytic activity against the autologous tumor cell line. Here, we demonstrate that this predominant Vbeta16 tumor-infiltrating lymphocyte recognizes a peptide encoded by a novel unconventional myosin class I gene. This peptide includes a mutation due to a single nucleotide substitution. The resulting Glu-->Lys replacement at position 911 of the coding sequence is critical to generate the recognized T cell epitope. These experiments demonstrate the existence of a natural tumor-specific cytolytic T cell response in a primary regressing human melanoma lesion. ( info) |
4/439. A MAGE-6-encoded peptide is recognized by expanded lymphocytes infiltrating a spontaneously regressing human primary melanoma lesion. In recent years, experiments based on the in vitro stimulation of either autologous peripheral blood lymphocytes or tumor-infiltrating lymphocytes with melanoma cells have shown that distinct members of the large MAGE gene family encode tumor-associated antigenic peptides. However, little is still known about natural anti-MAGE responses in vivo. We have studied a case of spontaneously regressing human melanoma, hypothesizing that in this unique situation, the host immune system had developed an efficient cytotoxic T lymphocyte (CTL) response against the cancer cells. Amongst the dense tumor infiltrate, certain clonal populations of T cells were shown to be amplified, thereby suggesting that an antigen-driven selection had occurred at the tumor site. One of the expanded tumor-infiltrating lymphocytes was shown to be a Vbeta13 CD8 CTL displaying a strong and selective cytotoxic activity against the autologous melanoma cells. Here we show that this cytotoxic T cell clone recognizes a MAGE-6-encoded peptide. MAGE-6 is therefore the fourth gene of the MAGE family shown to encode antigenic peptide recognized by T cells. Together, these data provide further evidence that T cell responses against MAGE antigens may naturally develop in vivo. ( info) |
5/439. Spontaneous partial fibrotic regression of a primary renal carcinoma: a case report. Spontaneous regression of non metastatic renal carcinoma is a very unusual finding in daily urologic practice. Furthermore this is the first case of a partial primary renal cancer remission documented by hystopathological specimens. Current hypothesis were discussed. ( info) |
6/439. Spontaneous remission of chiasmatic/hypothalamic masses in neurofibromatosis type 1: report of two cases. We report two children with neurofibromatosis type 1 showing enhancing masses on MRI suggesting neoplasms in the chiasm and hypothalamic region. In both patients no visual or endocrinal dysfunction was present. On serial MRI spontaneous partial remission was found, implying that a cautious approach to therapeutic management of similar cases should be taken. ( info) |
7/439. Spontaneous regression of a residual pineal tumor after resection of a cerebellar vermian germinoma. A case of multiple intracranial germ cell tumor in which a pineal tumor regressed spontaneously after resection of the cerebellar mass is reported. Immunohistochemical staining of the cerebellar mass showed that most of the infiltrating lymphocytes were positive for CD3 and CD8. The anti-Ki-67 monoclonal antibody MIB-1 staining of the resected tumor revealed a high MIB-1 positivity ratio (36.1%) among the large tumor cells, and TUNEL staining demonstrated that positivity in up to 6% of the tumor cells. Possible mechanisms responsible for this spontaneous regression including immunological responses and apoptosis induced by T lymphocytes are discussed. ( info) |
8/439. Regression of cancer following surgery. Postsurgical tumor regressions are rare but well-recognized entities. The causes of such phenomena are unknown but probably are multiple. Regression of any tumor must ultimately come about by changes in the host-tumor interaction which suddenly becomes unfavorable for tumor growth. This is likely a manifestation of changes in the immunocompetence of the host. There are many variables influencing the host-tumor interaction, and the study of tumor immunology is stil in its infancy. It is through the exploration and investigation of basic mechanisms of the immunology of cancer that the most potentially fruitful associations between tumor growth or regression and surgical manipulations may be made and applied to the treatment of cancer patients. ( info) |
9/439. Spontaneous regression of neuroblastoma. Case of spontaneous regression of neuroblastoma continue to occur in the present multimodal therapy era at institutions where physicians are prepared to withhold treatment on certain patients with residual primary or metastatic disease. From a survey of the 22 member institutions of Children's Cancer Study Group, seven hospitals submitted data on 24 neuroblastoma patients whose disease underwent regression after minimal, unusual, or no treatment. An analysis of these patients and of 33 patients form two large series in the literature shows that the majority of patients are infants with Stage II or Stage IVS disease. The spontaneous regression usually consists of complete disappearance of the disease, but in some neuroblastomas, maturation to ganglioneuroma takes place. The various factors that may influence regression are discussed. ( info) |
10/439. Eruptive widespread Spitz nevi: can pregnancy be a stimulating factor? Spitz nevus is most commonly a benign solitary lesion. Agminated or disseminated Spitz nevi represent an uncommon manifestation of this nevus. We report an unusual case of Spitz nevi arising and disseminating during pregnancy. ( info) |