CNTN6 mutations are risk factors for abnormal auditory sensory perception in autism spectrum disorders.

Contactin genes CNTN5 and CNTN6 code for neuronal cell adhesion molecules that promote neurite outgrowth in sensory-motor neuronal pathways. Mutations of CNTN5 and CNTN6 have previously been reported in individuals with autism spectrum disorders (ASDs), but very little is known on their prevalence and clinical impact. In this study, we identified CNTN5 and CNTN6 deleterious variants in individuals with ASD. Among the carriers, a girl with ASD and attention-deficit/hyperactivity disorder was carrying five copies of CNTN5. For CNTN6, both deletions (6/1534 ASD vs 1/8936 controls; P=0.00006) and private coding sequence variants (18/501 ASD vs 535/33480 controls; P=0.0005) were enriched in individuals with ASD. Among the rare CNTN6 variants, two deletions were transmitted by fathers diagnosed with ASD, one stop mutation CNTN6W923X was transmitted by a mother to her two sons with ASD and one variant CNTN6P770L was found de novo in a boy with ASD. Clinical investigations of the patients carrying CNTN5 or CNTN6 variants showed that they were hypersensitive to sounds (a condition called hyperacusis) and displayed changes in wave latency within the auditory pathway. These results reinforce the hypothesis of abnormal neuronal connectivity in the pathophysiology of ASD and shed new light on the genes that increase risk for abnormal sensory perception in ASD.

Quantitative studies on the localization of the cholinergic receptor protein in the normal and denervated electroplaque from Electrophorus electricus.

Electroplaques dissected from the electric organ of Electrophorus electricus are labeled by tritiated alpha1-isotoxin from Naja nigricollis, a highly selective reagent of the cholinergic (nicotinic) receptor site. Preincubation of the cell with an excess of unlabeled alpha-toxin and with a covalent affinity reagent or labeling in the presence of 10(-4) M decamethonium reduces the binding of [3H]alpha-toxin by at least 75%. Absolute surface densities of alpha-toxin sites are estimated by high-resolution autoradiography on the basis of silver grain distribution and taking into account the complex geopmetry of the cell surface. Binding of [3H]alpha-toxin on the noninnervated face does not differ from background. Labeled sites are observed on the innervated membrane both between the synapses and under the nerve terminals but the density of sites is approx. 100 times higher at the level of the synapses than in between. Analysis of the distance of silver grains from the innervated membrane shows a symmetrical distribution centered on the postsynaptic plasma membrane under the nerve terminal. In extrasynaptic areas, the barycenter of the distribution lies approximately 0.5 micrometer inside the cell, indicating that alpha-toxin sites are present on the membrane of microinvaginations, or caveolae, abundant in the extrajunctional areas. An absolute density of 49,600 +/- 16,000 sites/micrometer2 of postsynaptic membrane is calculated; it is in the range of that found at the crest of the folds at the neuromuscular junction and expected from a close packing of receptor molecules. Electric organs were denervated for periods up to 142 days. Nerve transmission fails after 2 days, and within a week all the nerve terminals disappear and are subsequently replaced by Schwann cell processes, whereas the morphology of the electroplaque remains unaffected. The denervated electroplaque develops some of the electrophysiological changes found with denervated muscles (increases of membrane resting resistance, decrease of electrical excitability) but does not become hypersensitive to cholinergic agonists. Autoradiography of electroplaques dissected from denervated electric organs reveals, after labeling with [3H]alpha-toxin, patches of silver grains with a surface density close to that found in the normal electroplaque. The density of alpha-toxin binding sites in extrasynaptic areas remains close to that observed on innervated cells, confirming that denervation does not cause an increase in the number of cholinergic receptor sites. The patches have the same distribution, shape,and dimensions as in subneural areas of the normal electroplaque, and remnants of nerve terminal or Schwann cells are often found at the level of the patches. They most likely correspond to subsynaptic areas which persist with the same density of [3H]alpha-toxin sites up to 52 days after denervation. In the adult synapse, therefore, the receptor protein exhibits little if any tendency for lateral diffusion.

A novel calmodulin-binding protein, belonging to the WD-repeat family, is localized in dendrites of a subset of CNS neurons.

A rat brain synaptosomal protein of 110,000 M(r) present in a fraction highly enriched in adenylyl cyclase activity was microsequenced (Castets, F., G. Baillat, S. Mirzoeva, K. Mabrouk, J. Garin, J. d'Alayer, and A. Monneron. 1994. Biochemistry. 33:5063-5069). Peptide sequences were used to clone a cDNA encoding a novel, 780-amino acid protein named striatin. Striatin is a member of the WD-repeat family (Neer, E.J., C.J. Schmidt, R. Nambudripad, and T.F. Smith. 1994. Nature (Lond.). 371:297-300), the first one known to bind calmodulin (CaM) in the presence of Ca++. Subcellular fractionation shows that striatin is a membrane-associated, Lubrol-soluble protein. As analyzed by Northern blots, in situ hybridization, and immunocytochemistry, striatin is localized in the central nervous system, where it is confined to a subset of neurons, many of which are associated with the motor system. In particular, striatin is conspicuous in the dorsal part of the striatum, as well as in motoneurons. Furthermore, striatin is essentially found in dendrites, but not in axons, and is most abundant in dendritic spines. We propose that striatin interacts, through its WD-repeat domain and in a CaM/Ca(++)-dependent manner, with one or several members of a surrounding cluster of molecules engaged in a Ca(++)-signaling pathway specific to excitatory synapses.

Concurrent overproduction of synapses in diverse regions of the primate cerebral cortex.

Synapses develop concurrently and at identical rates in different layers of the visual, somatosensory, motor, and prefrontal areas of the primate cerebral cortex. This isochronic course of synaptogenesis in anatomically and functionally diverse regions indicates that the entire cerebral cortex develops as a whole and that the establishment of cell-to-cell communication in this structure may be orchestrated by a single genetic or humoral signal. This is in contrast to the traditional view of hierarchical development of the cortical regions and provides new insight into the maturation of cortical functions.

Economic implications of hepatic arterial infusion chemotherapy in treatment of nonresectable colorectal liver metastases. Meta-Analysis Group in Cancer.

BACKGROUND: Approximately 20% of patients with colorectal cancer die of metastases confined to the liver. A meta-analysis recently performed by our group confirmed that in these patients hepatic arterial infusion of 5-fluoro-2'-deoxyuridine, compared with intravenous chemotherapy with fluoropyrimidines or supportive care (including symptom palliation when necessary), improved tumor response. PURPOSE: Because of the high cost of hepatic arterial infusion, we undertook a cost-effectiveness analysis that related the cost of such therapy to its medical efficacy. METHODS: The patient population was drawn from the seven randomized clinical trials included in the meta-analysis and included individual data on 654 patients. Of these seven trials, five compared hepatic arterial infusion and intravenous chemotherapy and two compared hepatic arterial infusion and a control group in which some patients could be left untreated. Patients assigned to receive hepatic arterial infusion made up the hepatic arterial infusion group; the other patients constituted the control group. The measures of efficacy were survival and tumor response. Health-care costs (in 1995 U.S. dollars) were computed over the duration of patient follow-up and were derived from actual costs in two centers, one at Henri Mondor Hospital (Paris, France) and the other at Stanford University Medical Center (Palo Alto, CA). The total cost of treatment included the initial procedure, chemotherapy cycles, and main complications. RESULTS: The mean gain in life expectancy in the hepatic arterial infusion group compared with the control group was 3.2 months (standard error = 1.0 month). For patients treated by hepatic arterial infusion in Paris, the hepatic arterial infusion pump, initial hospitalization, and the entire process (including follow-up and complications) cost, on average, $8400, $15172, and $29562, respectively; in Palo Alto, these costs were $4700, $13784, and $25 208, respectively. For patients in the control groups in Paris and Palo Alto, the total treatment costs were, on average, $9926 and $5928. The additional costs of hepatic arterial infusion over control treatment were $19636 in Paris and $19280 in Palo Alto. The cost-effectiveness (i.e., the additional cost divided by the additional benefit) with respect to survival of the patients in the hepatic arterial infusion group compared with the patients in the control group was $73635 per life-year in Paris and $72300 per life-year in Palo Alto. CONCLUSIONS AND IMPLICATIONS: The cost-effectiveness of localized chemotherapy for colorectal liver metastases is within the range of accepted treatments for serious medical conditions, although it might be considered borderline by policy-makers in some countries. Prospective clinical trials should be conducted to more definitively answer this question.

Innervation of avian latissimus dorsi muscles and axonal outgrowth pattern in the posterior latissimus dorsi motor nerve during embryonic development.

The distribution of the innervation to the anterior latissimus dorsi (ALD) and posterior latissimus dorsi (PLD) muscles of the chicken are described on the day of hatching and 6 weeks later using electron microscopy. In the ALD muscle, there are 5,000 muscle fibres and 374,000 endplates supplied by about 169 skeletomotor axons; in the PLD muscle, there are 12,000 focally innervated muscle fibers supplied by about 20 skeletomotor axons. On the cell surface of the muscle fibers the mean total subsynaptic area contacted by each motor axon is comparable in the ALD and PLD muscles. The growth pattern of the axons in the PLD motor nerve was described from the ninth day in ovo up to 6 weeks after hatching. The axons arrive in the PLD muscle in two successive waves: first, the large somatic axons which are already present before the ninth day in ovo and second, the small autonomic axons which continue to accumulate until hatching. The total number of somatic axons decreases from the ninth day until the hatching day when it reaches its definitive value. This decrease takes place during a period when the numbers of myofibers and of endplates dramatically increase, and it coincides with the axonal segregation by the Schwann cells. The myelination of the axons starts on the 15th day in ovo and is essentially complete upon hatching. Despite the decreasing number of somatic axons in the PLD nerve, the decrease in number of nerve endings per PLD endplate and the increasing number of PLD endplates per PLD muscle, it was found that between the 16th day in ovo and 6 weeks after hatching the mean number of axonal branches per PLD motor axon does not decrease.

Tempo of neurogenesis and synaptogenesis in the primate cingulate mesocortex: comparison with the neocortex.

In the neocortex, the onset of the rapid phase (phase 3) of synaptogenesis occurs after the end of neurogenesis. However, we still do not know whether or not these two developmental events are causally related. The present study compares the time-course and tempo of neurogenesis and synaptogenesis in the anterior cingulate cortex (area 24 of Brodmann) and in the primary visual cortex (area 17) in a series of pre- and postnatal rhesus monkeys. Autoradiographic analysis of animals fetally injected with 3H-thymidine showed that all neurons destined for area 24 are generated by embryonic day 70, which is 30 days earlier than in area 17. The rapid phase of synaptogenesis in area 24 starts during the third embryonic month and continues at the same rate through the remainder of gestation and the first 2 months after birth, as has been seen in neocortical areas examined previously. Statistical analysis of the linear portions of the rapid phase indicates that, although neurogenesis in area 24 is completed 1 month earlier than in area 17, the rapid phase of synaptogenesis occurs 41 days later. Moreover, the tempo of synaptic accretion was remarkably similar to that in motor, somatosensory, visual, or associational areas. All were grouped within the same time window of about 40 days, centered at birth. After the second postnatal month, synaptic density in area 24 remains at a high level until sexual maturity. This work shows that the rapid phase of synaptogenesis in the cingulate mesocortex is not linked temporally to the end of neurogenesis. We suggest that it is regulated by the same genetic or humoral factors that control synaptogenesis in the phylogenetically newer neocortical areas.

Management of breast cancer in the elderly.

The management of breast cancer in elderly women was analysed by a retrospective study of 150 women over 70 years old referred to our department between 1984 and 1988. 80 were T1-T2, 33 were T3 and 34 were T4. 107 were N0 and 43 were N1-N2. 16 women (11%) were in poor health, preventing conventional treatment. Treatment choice varied with age: 60% of the women aged 70-79 (group 1) and 23% of the oldest women (group 2) were treated conventionally. The use of surgery decreased with age and surgical procedures were conventional in only 85% of the group 1 women and in 56% of the group 2 women. Definitive radiation therapy was used more frequently in the oldest women, as was primary hormone therapy. Quality of follow-up also varied with age. Five-year survival rates were still high in both groups while relapses were frequent. Breast cancer was consequently a frequent cause of death. The increase in the proportion of elderly people with breast cancers over the next few years will require validated guidelines. Specific protocols and specific rules of management must be drawn up.

Liver complications in lymphomas treated with a combination of chemotherapy and radiotherapy: preliminary results.

From May 1978 to May 1981, a total of 20 patients (18 patients with Non Hodgkin Lymphomas + 2 patients with Stage IV Hodgkin's disease) were treated with chemotherapy and whole or upper abdominal radiotherapy. All the patients were in complete remission at the time of irradiation. Shielding of the kidneys was effected at the start of treatment and the right lobe of the liver was shielded after a dose of 20 Gy was delivered. As of January 1982, 17 of the patients were alive and free of disease with a follow-up ranging from 6 to 32 months (mean follow-up of 18.5 months). Two patients were dead from their disease. Alterations in liver chemistry were observed in 5 patients, clinical jaundice or transient hepatomegaly along with changes in liver chemistry in 4 patients, classical veno-occlusive disease in 2 patients and 7 of the patients did not develop any complication. No death from complications were observed. The contribution of the following factors such as radiotherapy dose to the liver, drugs, nutritional status and associated medical conditions, towards the development of complications have been analyzed in detail.

A comparison between low dose rate radiotherapy and conventionally fractionated irradiation in moderately extensive cancers of the oropharynx.

We report the comparative results for local tumor control between two groups of patients treated by radiotherapy fractionated in a conventional manner at normal high dose rate (29 patients with 2 years minimum follow-up and 24 patients with 3 years minimum follow-up) and by low dose rate radiotherapy (19 patients with 2 years minimum follow-up, 14 patients with 3 years minimum follow-up) with moderately extensive cancers of the oropharynx (T2b-T3a, 3-5 cm in diameter). At 2 and 3 years follow-up, the number of local recurrences in the patients treated with low dose rate radiotherapy is half (26 and 21%) that for those treated with conventionally fractionated radiation at normal high dose rates (52 and 54%). These results require more rigorous confirmation.

Update on low dose rate irradiation for cancers of the oropharynx--May 1986.

At the conclusion of our recently published article in this Journal on low dose rate irradiation in moderately extensive cancers of the oropharynx, we updated our results in May 1986. Here we report on an expanded group of 65 patients with a 2 year minimum follow-up; 32 patients were treated by low dose rate irradiation and 33 by conventional fractionation. Forty-four percent (14/32) low dose irradiation patients survived with NED vs 8/33 (24%) conventional fractionation patients. The highly significant differences in the level of local recurrences between patients treated by low dose rate irradiation, 5/32 (16%), compared with conventional fractionation, 20/33 (61%), highlights the enhanced efficacy of the low dose rate irradiation technique in the local cure of cancers of the oropharynx. This superior local control however is achieved at the cost of a number of necrosis, 5/32 (16%).

Radiotherapy in the management of cutaneous epidemic Kaposi's sarcoma.

Between June 1986 and December 1988, we treated 149 patients who had AIDS-related epidemic Kaposi's sarcoma with cutaneous irradiation. According to Mitsayasu's staging, 34 patients (23%) had Stage I disease, 82 (55%) Stage II, 0 Stage III, and 33 (22%) Stage IV. Fifty-eight patients (39%) had previously presented with one or more opportunistic infections. Ninety-four patients (63%) had received previous treatment of their Kaposi's sarcoma: 85 (57%) with interferon and 43 (29%) with vinblastine. Among the 149 patients, we treated 88 (59%) with extended cutaneous irradiation using 4- and/or 8-MeV electron beam energy and 61 patients (41%) with localized irradiation using 45-kVp x-ray energy. The total prescribed dose was 30 Gy: 20 Gy in 2 weeks (2.5 Gy/fraction, 4 times/week), followed by 2 weeks of no irradiation, and then 10 Gy in one week by the same dose schedule. Twenty patients (13%) with edema of the lower limbs were treated using 4-Mv photon therapy with bolus. Of the 131 evaluable patients, 63% achieved a complete remission (CR) and 30% a partial remission (PR) after a mean period of 1.5 months (range: 0.5-3 months). The clinical disease stage, anatomic site, and irradiation technique did not significantly influence the remission rates, although we noticed a higher CR rate when localized irradiation was used (71% vs 55.5% for localized and extended irradiation, respectively; p = 0.08). The overall tolerance was acceptable. Complications were severe epidermitis with skin ulcerations (8% of patients), exudative epidermitis (26%), dry epidermitis (60%), and varying degrees of erythema (6%). Of the 87 patients whose AIDS remained relatively clinically stable during the observation period, recurrences occurred in 56 (64%) after an average of 5.5 months (range: 1.5-12 months). We conclude that radiotherapy is useful and can be recommended as a palliative treatment to relieve pain and physical discomfort or to achieve cosmetic improvements for patients with epidemic Kaposi's sarcoma. We also conclude that radiotherapy is most beneficial in the early stages of disease, when localized treatment is practical.

Radiotherapy in the management of epidemic Kaposi's sarcoma.

PURPOSE: This study is presented to help define the role of radiotherapy in the management of epidemic Kaposi's sarcoma. METHODS AND MATERIALS: Between June 1986 and June 1993, we treated 453 patients who had acquired immunodeficiency syndrome related Kaposi's sarcoma. Two hundred fifty-two patients (55.6%) had received previous treatment for their Kaposi's sarcoma: 228 (55.3%) with interferon, and 116 (25.6%) with Vinblastine. Depending on both tumour size and location, patients were treated with extended cutaneous irradiation using 4 MeV electron beam energy and/or localized irradiation using 45-100 kV x-ray (cutaneous lesions), or 4 MV x-ray (oral tumours). A total of 5015 courses of radiation therapy was given. The intention of the treatment was closely linked to the anatomic sites. Multiple courses of treatment ranging from 10 to 20 Gy (2.5 Gy/fraction, 4 times/week) were used for Kaposi's sarcoma involving conjunctiva (n = 32 treatments), eyelids (n = 306), lips (n = 170), hands (n = 208), feet (n = 417), penis (n = 131), oral mucosa (n = 43), and anal region (n = 5). A second group including other cutaneous sites (face, trunk, limbs) was treated with a dose of 30 Gy (20 Gy in 2 weeks followed by 2 weeks rest and then a second series of 10 Gy in 1 week). RESULTS: For the first group, tolerance was generally good excluding oral cavity irradiation, with an effective palliation of symptoms (87.8% overall rate of objective responses); an enhanced mucosal reactions was noted in patients receiving oropharyngeal irradiation. For the second group, a complete regression rate of 85% was observed; tolerance was acceptable: complications were severe epidermitis with skin ulceration (5%), exsudative epidermitis (26%), dry epidermitis (60%), and varying degrees of erythema (9%). There was a significant correlation between risk of recurrence (overall recurrence rate of 71% after an average of 7.5 months) and occurrence of opportunistic infections: 85% of recurrences appeared concomitantly with accelerated course of acquired immunodeficiency syndrome. CONCLUSIONS: We conclude that radiotherapy is an efficient treatment for epidemic Kaposi's sarcoma (EKS): doses of 15.2 Gy for oral lesions and 20 Gy for lesions involving conjunctiva, eyelids, lips, hands, feet, penis, and anal region were sufficient to produce shrinkage of the tumour and good palliation of symptoms. For the other cutaneous sites, 30 Gy local field irradiation could be safely given with better short-term response. Prophylactic measures with antifungal treatment should be systematically associated with oropharyngeal irradiation, to improve tolerance to the treatment.

Management of epistaxis in Rendu-Osler disease: is brachytherapy effective?

PURPOSE: This paper reviews the results of intranasal brachytherapy for epistaxis in 43 patients with Rendu-Osler disease treated between 1971-1991 at Henri Mondor Hospital. METHODS AND MATERIALS: 2-3 intranasal catheters were afterloaded with 192Ir sources. Computer dosimetry was performed and then the dose was prescribed to an isodose thought to cover the nasal mucosa. The dose rate ranged from 0.16 Gy/h-0.63 Gy/h with a median of 0.34 Gy/h. Dose at one application ranged from 15-35 Gy with a median of 30 Gy. The severity of epistaxis was graded 1 to 5. RESULTS: The time to recurrence of significant epistaxis ranged from 6-178 months with a median of 24 months. The dose prescribed did not correlate with control rate. The only brachytherapy complication was septal perforation in 4 patients; in one this was a result of repeated nasal coagulation. CONCLUSION: We suggest that intranasal brachytherapy is a useful modality in the management of epistaxis in Rendu-Osler disease.

The indications for total cutaneous electron beam radiation therapy of mycosis fungoides.

From 1977 to 1984, we treated 34 patients with mycosis fungoides and 9 patients with B cutaneous lymphomas. Eighteen patients with mycosis fungoides were treated with total skin electron irradiation (TSEI) and had a minimum follow-up of 15 months (range 15 months to 7 years). The lowest electron energy of the linear accelerator was 8 MeV therefore we placed a plexiglas screen between the patient and the machine; the resulting electron energy was 4 MeV. The total dose was 30 Gy delivered in 12 fractions over 40 days. There were 8 males and 10 females. The median age was 48 years (ranging from 13 to 78 years). All patients were staged as follows: Stage A = superficial lesions covering less than 50% of the body surface; Stage B = superficial lesions covering more than 50% of the body surface; Stage C = tumors involving the skin, lymph nodes and/or visceral organs. Five patients with Stage A (5/5) and 5 patients with Stage B (5/5) had a complete remission, 1 stage A patient relapsed 6 months after completion of treatment. All the Stage B patients recurred between 3 and 15 months. The recurrences were localized to the skin and were well controlled with topical nitrogen mustard or puvatherapy. Among the Stage C patients, 3 did not respond to treatment and died of their disease; the remaining 5 patients achieved complete remission but they all relapsed from 2 to 9 months following completion of treatment. The median follow-up was 32 months and the average time for relapse was 6.5 months. All relapses except one (15 months) occurred within the first year. We feel that total skin electron irradiation is indicated in Stage A and B patients. However, we feel Stage C patients should receive TSEI for palliative purposes only.

Interstitial radiation therapy for squamous cell carcinoma of the tonsillar region: the Creteil experience (1971-1981).

From July 1971 to December 1981, 33 selected patients with T1, T2 tumors of the tonsillar region were treated according to the following protocol: 1. Telecobalt therapy to the primary site and to neck nodes to a dose of 45 Gy. 2. Brachytherapy to the primary site to a dose of 30 Gy using iridium 192. 3. Boost dose to involved neck nodes with electrons, or radical neck dissection, whether N1, N2, or N3. The actuarial disease-free survival was 76% when all patient groups were included and 80% for the N0 patients. The local control rate was 100%. Disease control in the neck was 94% overall and 100% for the N0 group. These results favor the use of this protocol for superficial, minimally infiltrating tumors less than 4 cm in diameter, without obvious extension to the base of the tongue or retromolar trigone.

Radiation therapy for carcinoma of the pinna using iridium 192 wires: a series of 70 patients.

From January 1970 to November 1982, 70 patients with carcinoma of the pinna were treated by interstitial irradiation. An afterloading technique with Iridium 192 wires was used. One patient recurred and had a total pinnectomy followed by 60 Gy external radiation. This patient was alive without evidence of disease at 134 months. Three patients who had tumors greater than 4 cm in size at presentation developed late necrosis which required subsequent total pinnectomy. Cosmetic results were assessed in 55 patients and were good with few late sequelae (in 78% of cases (36/46) when the tumor measured less than 4 cm, but only in 1/9 when the tumor measured more than 4 cm). We advocate interstitial Iridium 192 irradiation for treatment of pinna tumors smaller than 4 cm. None of 39 patients with squamous cell carcinoma had biopsy proven cervical lymph node metastasis at the time of diagnosis. Four patients with squamous cell carcinoma (4/39: 10%) later developed a regional nodal metastasis after treatment of the pinna. All four relapsed in the parotid region and were managed by partial parotidectomy and neck dissection followed by external irradiation. One of these four patients died from uncontrolled cervical node disease. In our opinion, when regular follow-up is dependable, it is reasonable to save treatment of the cervical nodes for those patients who relapse with involved metastatic cervical nodes.

Second head and neck cancers following radiation therapy of T1 and T2 cancers of the oral cavity and oropharynx.

The risk of second cancer in the head and neck region following definitive radiation therapy was evaluated among 600 patients who were treated for T1 and T2 cancers of the oral cavity and oropharynx at the Henri Mondor hospital between January 1970 and March 1987. Seventy-five patients (12.5%) were managed with external irradiation only, 243 (40.5%) with RT and Iridium 192, and 282 (47%) with Iridium 192 alone. One hundred fifteen patients (19%) developed a second cancer from 3 to 183 months after initial therapy (median: 32 months), including 69 patients (11.5%) in whom the second malignancy was diagnosed in the head and neck region. An increased and constant actuarial risk of development of second head and neck cancer was found (2.7%/year of observation). Univariate analysis showed that age, sex, stage, and modality of the initial treatment did not influence the risk of second head and neck cancer; there was a greater risk of second head and neck malignancy for those patients with soft palate carcinoma (p less than 0.05). Multivariate analysis revealed that the only group of patients who developed a second head and neck cancer more frequently were those who were irradiated with Iridium 192 only (p = 0.0076). There was a trend toward a greater risk of second head and neck malignancy for those with soft palate carcinoma (p = 0.059). Radical treatment of the second head and neck malignancy by surgery and/or re-irradiation was performed for 67% of patients. Patients initially treated by Iridium 192 only could undergo salvage treatment more often than those who previously received external beam radiotherapy (79% vs 53%, p = 0.02). The overall 2-year and 5-year survivals after the diagnosis of the second head and neck cancer were 32% and 10%, respectively.

Iridium-192 curietherapy for T1 and T2 epidermoid carcinomas of the floor of mouth.

From 1970 to 1986, 117 patients with T1 (47) or T2 (70) epidermoid carcinomas of the floor of the mouth (SCC) were treated by iridium-192 implantation (192 Ir). The dose was prescribed according to the Paris System and varied over those years. Follow-up information was available on 116 patients. There were 46 T1N0, 47 T2N0, and 23 T2N1-3. Neck management varied for the 93 N0 patients consisting of surveillance (24 T1, 17 T2) or elective neck dissection (22 T1:all pN-, 30 T2: 20 pN-, 10 pN+). Cause specific survival rates were 94% for T1N0, 61.5% for T2N0, and 28% for T2N1-3 at 5 years. Primary local control was 93.5%, 74.5%, and 65%, respectively, and 98%, 79%, and 65% after salvage. Patients with gingival extension or a tumor size over 3 cm (T2b) had a local control of 50% (9/18) and 58% (15/26), respectively. Nodal control was 93.5% for Stage I, 85% for Stage II, and 48% for T2N1-3 patients. There was no difference in nodal control with regard to treatment policy for Stage I-II patients. There were few complications including three deaths: two from surgery and one from 192 Ir. Nodal status, tumor size defined as T1, T2a (less than or equal to 3 cm), T2b (greater than 3 cm), and gingival extension were the only independent prognostic factors. The management of T1N0 and T2N0 SCC by 192 Ir to a dose of 65 or 70 Gy, using the Paris System, is recommended for lesions 3 cm or less and without gingival extension.

Influence of dose rate on local control of breast carcinoma treated by external beam irradiation plus iridium 192 implant.

From 1971 to 1983, 20 T1, 267 T2, and 53 T3 biopsy-proven adenocarcinomas of breast were definitively managed by radiotherapy. The breast and regional nodes received 45 Gy of 60Co irradiation in 25 fractions over 5 weeks (45 Gy/25/5 wks). Electrons were used to deliver a further 15 Gy/7/1.5 weeks to the internal mammary chain and 25 Gy/11/2.5 weeks to the lower axilla. The primary tumor was boosted by Iridium 192 implant for a further 37 Gy prescribed at 85% of the basal dose rate (Paris system). Rigid needles were secured by templates in single plane (58/398) or double plane (340/398) geometry. Results of the 340 two-plane implants have been analyzed to look for a possible influence of dose rate on local control. Follow-up for patients free of local recurrence is 4-204 months (median: 92 months). The 340 tumors were divided into three groups according to dose rate: 0.32-0.49 Gy/hr (n = 95), 0.50-0.59 Gy/hr (n = 120), and 0.60-0.90 Gy/hr (n = 125). The three groups are statistically comparable according to age, tumor size, mean 60Co dose, mean Iridium dose, overall treatment time, and follow-up. The local failure rate in the three groups is 27% (26/95), 20% (24/120), and 13% (16/125) (p less than 0.03, Chi square). At 15 years the estimated local control (Kaplan Meier) is 60%, 72%, and 84% (p less than 0.02, Logrank), respectively. This analysis indicates that there is a significant effect of dose rate on local control for carcinoma of the breast treated by combined external beam (45 Gy) plus Iridium 192 implantation (37 Gy). To maximize local control the authors recommend an implant dose rate of greater than or equal to 0.6 Gy/hr.