Maturation of tumours of the sympathetic nervous system

Refractory Stage M Ganglioneuroblastoma With Bone Metastases and a Favorable, Chronic Course of Disease: Description of a Patient Cohort

Refractory stage M neuroblastoma (NB) is associated with a poor prognosis and a progressive course of disease. Here, we describe a unique group of patients with a discrepant clinical course. Seven histologically confirmed ganglioneuroblastoma (GNB) (n=6) and differentiating NB (n=1) patients were identified who were diagnosed with stage M disease based on iodine-123-metaiodobenzylguanidine avid bone metastases. Six patients started on high-risk treatment, without tumor response (stable disease). Treatment was discontinued before the start of consolidation treatment because of refractory response in all patients. Unexpectedly, after cessation of treatment no progression of disease occurred. In 2 patients, the primary tumors expanded (>25%) very slowly during 1.5 and 3 years, and remained stable thereafter. Metabolically, a slow decrease of urinary homovanillic acid and vanillylmandelic acid levels and iodine-123-metaiodobenzylguanidine avidity was observed. All patients are alive with presence of metastatic disease after a median follow-up of 17 years (range: 6.7 to 27 y). Interestingly, at diagnosis, 6 patients were asymptomatic, 6 patients had GNB morphology, and 5 patients had meningeal metastases. These are all features seen in only a small minority of stage M patients. This GNB entity illustrates the clinical heterogeneity of neuroblastic tumors and can be used to further study the developmental origin of different NB subtypes.

Nonrandom distribution of metastases in neuroblastic tumors

Metastatic behavior of neuroblastic tumors was analyzed to determine whether the secondary distribution of tumor was random, or whether the pattern of metastases was predictable and related to tumor type. The authors reviewed the 64 patients subjected to complete autopsy who had metastases from a neuroblastoma, retinoblastoma, medulloblastoma, or pinealoblastoma. The organ and tissue distribution of metastases was recorded in relation to location of primary tumor, type of therapy, survival, and presence of central nervous system metastases. Data were analyzed using chi-square contingency tables, correlation coefficients, and cluster analysis. The results indicate that: (1) the development of central nervous system metastases from neuroblastoma correlates with the pattern of extracentral nervous system metastases; (2) the pattern of tumor metastases is altered by chemotherapy and/or radiation; and (3) regardless of the site of origin, neuroblastic tumors behave in a uniform manner with a nonrandom metastatic distribution in particular tissues within the central nervous system. Cluster analysis demonstrated patterns of neuroblastoma tumor metastases which were consistent with both Hutchison and Pepper syndromes. The findings suggest that a random distribution, as might be secondary to blood flow, does not account for metastatic patterns, but rather that there are preferential patterns of growth, possibly reflecting trophic tendencies in neoplasms.

Primary pulmonary ganglioneuroblastoma in an adult: maturation, involution and the immune response

The features of a primary pulmonary ganglioneuroblastoma occurring in an adult are presented. The tumour showed evidence of both maturation and involution. Maturation appeared to be occurring in a centrifugal manner, a rim of mature ganglioneuromatous tissue enclosing the primitive neuroblastoma. Necrosis of the neuroblastomatous element was widespread and associated with deposition in the walls of numerous small vessels of an amorphous eosinophilic amyloid-like material. Accumulation of this material had led to occlusion of some vessels with resultant necrosis of related tumour. A collarette of lymphocytes surrounded the tumour, and lymphocytic aggregates were prominent at the interface between neuroblastoma and ganglioneuroma. Despite widespread vascular invasion, the patient remains well and apparently tumour-free, 2 1/2 years post-resection. The appearances may represent a combined cellular and humoral host response, and a possible relationship of this response to tumour maturation is suggested. The potential role of immunostimulation in the treatment of neuroblastoma is discussed.

Maturing neuroblastoma and ganglioneuroblastoma: a study of four cases with long survival

A retrospective study of four tumours of the peripheral nervous system originally diagnosed as neuroblastomas or ganglioneuroblastomas has been made. The patients have all survived since the original diagnosis. Evidence of residual tumour was seen only in one patient, and was associated with evidence of increasing histological differentiation over a period of time. Maturation of primitive cell types is known to alter the prognosis of neuroblastic tumours. It is suggested first, that even minimal evidence of maturation indicates a better prognosis. Second, that evidence of maturation may be uneven, small areas occurring in otherwise totally undifferentiated tumours, or, immature areas remaining even in apparently benign fully mature tumours; if these areas show maturation the prognosis remains good and the tumour should not be confused with a composite ganglioneuroblastoma. Third, that maturing tumours may behave in a malignant fashion, invade and metastasise, but but with maturation of the primary tumour and its metastases the ultimate prognosis may be better than the initial behaviour suggests.

Why are ovarian teratomas benign whilst teratomas of the testis are malignant?

A mechanism is suggested to account for the fact that most ovarian teratomas are benign (dermoid cysts) whereas testicular teratomas are almost always malignant. The mechanism advanced assumes that malignancy is cause by a recessive mutation, and then shows that the known facts of germ-cell development will produce the homozygous (malignant) state in the male but the heterozygous counterpart in the female. It is proposed that the benign nature of ovarian teratomas is a reflection of this heterozygous genotype.

Neurogenic tumours with an intrathoracic localization

This paper is a clinicopathological review of patients suffering from intrathoracic neurogenic tumours.