Search PubMed⌕ Search

Biomedical subjects

J J Jenkins

Publications and source records attributed to J J Jenkins.

At least 73 records · Page 4Linked to original sources
PubMed1996

Medulloblastoma with brain stem involvement: the impact of gross total resection on outcome.

We studied the impact of gross total resection on progression-free survival (PFS) and postoperative morbidity in 40 children with locally advanced medulloblastoma characterized by tumor invading the brain stem. These patients represented 40% of children treated for newly diagnosed medulloblastoma at a pediatric oncology center over a 10-year period. All patients underwent aggressive initial surgical resection. Review of surgical and neuroimaging findings documented gross total resection in 13 cases, near-total resection (< 1.5 cm2 residual tumor on imaging) in 14 cases, and subtotal resection (> than 50% resection with > or = 1.5 cm2 residual) in 13 cases. Overall, 85% of patients had a > 90% resection. Subsequent therapy comprised craniospinal irradiation in all cases and chemotherapy on institutional or cooperative group protocols in 35 cases. At a median follow-up of 4 years, postirradiation PFS is 61% (SE = 10%). There was no difference in PFS for patients who underwent gross total resection compared to those with any detectable residual tumor (p > 0.70). The posterior fossa syndrome occurred in 25% of cases, and had no apparent relationship to the extent of resection (p > 0.5, exact test). In this series, true gross total resection was not associated with a PFS advantage when compared to strictly defined near-total and subtotal resection. Although there was no operative mortality, the frequency of the posterior fossa syndrome is of concern and emphasizes the need for careful consideration of the risk/benefit ratio in the surgical approach to this subgroup of patients.

Brain Neoplasms↗
PubMed1996

Fractures in children treated with radiotherapy for soft tissue sarcoma.

There is a clear association between multimodal therapy for bone tumors and the development of skeletal complications; however, this has not been addressed in children with soft tissue sarcomas. We reviewed records of the 70 children treated for soft tissue sarcoma of the lower extremity at St. Jude Children's Research Hospital between 1962 and 1991. Of the 12 patients who received radiation after surgical excision of their tumors, three subsequently developed fractures. Two of the three had also received chemotherapy. Our findings indicate that, although the risk of fracture after therapy for soft tissue sarcoma may be multifactorial, radiation may play a significant role. Minimizing the size of surgical incisions, improving radiotherapy techniques, maximizing chemotherapy, and emphasizing physical therapy and appropriate follow up can all serve to decrease long-term toxicities. Such optimal use of therapy could subsequently reduce side effects, such as osteoporosis and muscle and bone atrophy, that predispose patients to fractures.

Adolescent↗
PubMed1995

A phase II evaluation of thiotepa followed by other multiagent chemotherapy regimens in infants and young children with malignant brain tumors.

BACKGROUND: Chemotherapy may be used to delay the need for cranial irradiation in infants and young children with malignant central nervous system (CNS) tumors. The polyfunctional alkylator thiotepa (TT) possesses significant in vitro and in vivo activity in many central nervous system tumors. Before the introduction of a multiagent chemotherapy previously shown to be active in such tumors, thiotepa alone was evaluated in an upfront therapeutic window. METHODS: Twenty young children with CNS tumors (19 newly diagnosed, 1 recurrent) were treated with two cycles of TT before response evaluation. Patients on thiotepa without disease progression went on to receive further chemotherapy consisting of alternating cycles of cyclophosphamide plus vincristine, cisplatin plus etoposide, and further TT. Patients with disease progression received radiation therapy. RESULTS: Low objective rates of response and poor survival led to early study termination. Of 17 patients evaluable for response, 6 (35%) demonstrated disease progression during initial TT therapy. Only two objective responses were noted, both in patients with medulloblastoma. Among the 19 patients evaluable for survival, the overall and progression free survivals were 45% and 20%, respectively, at 3 years postdiagnosis. Myelosuppression was the dominant treatment-related toxicity. CONCLUSIONS: Although the numbers of patients were small, thiotepa as used in this study was associated with a poor objective response rate and an unacceptably high rate of disease progression. These results may be partly related to TT's significant myelosuppressive effects and the postponement of more effective chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

Unusual cutaneous toxicity following treatment with dactinomycin: a report of two cases.

Dactinomycin-induced cutaneous toxicity is rare in pediatric patients not receiving radiation therapy. We describe dactinomycin-related lesions in the axilla, groin, and central line exit site of two children treated for rhabdomyosarcoma, neither of whom had received radiation treatment. One patient was initially treated with systemic antifungal therapy, and developed recurrent lesions on reexposure to the drug. The other was noted to have mild, diffuse hyperpigmentation. Skin biopsies revealed interface dermatitis with syringometaplasia in both cases. Both children recovered uneventfully within 4 weeks. Recognition of unusual rashes with a characteristic distribution in patients receiving dactinomycin should aid in diagnosis, and help avoid unnecessary therapeutic procedures.

Child↗
PubMed1995

Imaging features of ovarian metastases from colonic adenocarcinoma in adolescents.

This paper describes the imaging features of ovarian metastases from adenocarcinoma of the colon in adolescent females. We reviewed retrospectively abdominal and pelvic computed tomographic and pelvic ultrasound examinations, histologic slices, and clinical charts of six adolescent females with ovarian metastases secondary to adenocarcinoma of the colon. One patient had ovarian metastasis at presentation and was presumed to have a primary ovarian tumor. The ovarian metastases were either solid (n = 3), complex with both solid and cystic components (n = 2), or multilocular cysts (n = 1). The ovarian lesions were large, ranging from 6 cm to 18 cm in diameter. Colorectal carcinoma in adolescent females is frequently associated with ovarian metastases. One imaging characteristic differs in adult and adolescent ovarian metastases, although they do have features in common: in adolescents, a smaller proportion of colorectal ovarian metastases are multicystic (17%) compared with the adult series (45%). These lesions are frequently large and may be complex, multicystic, or solid. Although it is a rare disease, the differential diagnosis of adnexal masses in adolescent females should include ovarian metastases from adenocarcinoma of the colon.

Adenocarcinoma↗
PubMed1995

Preirradiation chemotherapy with carboplatin and etoposide in newly diagnosed embryonal pediatric CNS tumors.

PURPOSE: We evaluated the clinical efficacy of preirradiation carboplatin (CARBO) and etoposide (VP-16) in 25 patients with newly diagnosed embryonal CNS tumors. PATIENTS AND METHODS: Sixteen patients with high-risk medulloblastoma and nine with other embryonal tumors were treated with two daily doses of CARBO 350 mg/m2 and VP-16 100 mg/m2 (CARBO/VP) every 21 days for four cycles before standard craniospinal irradiation. Patients with disease progression (PD) before radiation therapy were additionally treated with intensive postirradiation cyclophosphamide (CYCLO) and vincristine (VINC). RESULTS: Among 23 assessable patients, 48% (95% confidence interval, 27% to 69%) had a complete response (CR) or partial response (PR) to CARBO/VP; eight had PD. Among the subgroup of 15 assessable patients with medulloblastoma, 53% had a CR or PR (95% confidence interval, 27% to 79%) and five PD. The toxicity of CARBO/VP was predominantly hematologic; although grade IV neutropenia was common, only five episodes of febrile neutropenia occurred. Only thrombocytopenia was a more common toxicity than in other reported chemotherapy regimens; ototoxicity was less common than in cisplatin (CDDP) regimens. CONCLUSION: The responses and survival associated with neoadjuvant CARBO/VP are similar to those with CDDP-containing and other neoadjuvant drug regimens. Although the rate of progression with this regimen may be higher than with similar CDDP-containing regimens, the numbers of patients in other published studies of these agents are too small to detect meaningful statistical differences. Future studies must balance the apparently comparable efficacy of CARBO and CDDP with their differing toxicities.

Adolescent↗
PubMed1995

Low-grade astrocytoma with neuraxis dissemination at diagnosis.

Little is known about low-grade astrocytoma with neuraxis dissemination at diagnosis. A review of medical records identified this phenomenon in eight of 150 pediatric patients evaluated between 1985 and 1994 for histologically confirmed low-grade astrocytoma. These patients (five male and three female) ranged in age from 5 months to 20 years (median 8 years). Symptoms of neuraxis disease were minimal or absent. Primary tumor sites were the hypothalamus in four cases, brainstem/spinal cord in three, and temporal lobe in one. Patterns of dissemination (evaluated by computerized tomography and/or magnetic resonance imaging techniques) appeared to be related to the primary site: hypothalamic tumors metastasized along the ventricular cerebrospinal fluid pathways, and tumors in other locations disseminated along subarachnoid pathways. Following initial treatment with chemotherapy (in three), partial resection (in one), radiation therapy (in three), and chemotherapy plus irradiation (in one), four patients required salvage therapy for progressive or recurrent disease. Seven of the eight patients are alive with stable or progressive disease 6 to 105 months postdiagnosis (median 15 months). Low-grade astrocytoma with initial neuraxis dissemination is responsive to chemotherapy and radiation, a proportion showing periods of stable disease. The optimum therapy or combination of therapies remains unclear.

Adolescent↗
PubMed1995

Nonrhabdomyosarcomatous soft tissue sarcomas of childhood: formulation of a simplified system for grading.

Because of the rarity of pediatric nonrhabdomyosarcomatous soft tissue sarcomas, it is difficult to test standardized treatment protocols for individual tumor entities. Grading has been used successfully to predict outcome of adult sarcomas, but pediatric soft tissue tumors display a notable difference in clinical behavior when compared to older patients. To test systematically a standardized treatment strategy for pediatric nonrhabdomyosarcomastous soft tissue sarcomas devised by the Pediatric Oncology Group, the authors devised a grading schema using concepts of adult grading systems and integrating the unique clinical and morphologic features of pediatric sarcomas. Three grading tiers were devised: Grade I, which includes certain pediatric tumors with little propensity for malignancy; Grade II, which is composed of tumors excluded from Grades I or III by virtue of histologic diagnosis and having <5 mitoses/10 high-power fields or <15% geographic necrosis; and Grade III, which comprises certain tumors known to be clinically aggressive by virtue of histologic diagnosis and non-Grade I tumors with >4 mitoses/10 high-power fields or > 15% necrosis. An initial retrospective analysis on a series of lesions treated at a single institution indicated a strong predictive value for grading. Subsequent prospective studies by the Pediatric Oncology Group continue to verify the prognostic value of pediatric nonrhabdomyosarcomatous soft tissue sarcoma grading, and studies on individual pediatric nonrhabdomyosarcomatous soft tissue sarcomas, such as synovial sarcoma, also indicate the relatively poor outcome of higher grade lesions. Grade can be used to predict outcome of pediatric nonrhabdomyosarcomatous soft tissue sarcomas and to devise treatment strategies for experimental protocols.

Adolescent↗
PubMed1994

Thymic carcinoma with a defective Epstein-Barr virus encoding the BZLF1 trans-activator.

The diagnosis of Epstein-Barr virus (EBV)-associated carcinomas is often heralded by high antibody titers to the viral replicative antigens, suggesting EBV reactivation may be a factor in tumor evolution. EBV DNA and nuclear antigen was detected in a newly diagnosed thymic carcinoma. Polymerase chain reaction analysis revealed the presence of a rearranged EBV DNA fragment, BamHI WZhet. This rearrangement is found in a defective EBV that up-regulates the BZLF1 (BamHI Z leftward reading frame) gene product in vitro and induces the EBV lytic cycle. Molecular analysis of the EBV termini demonstrated low levels of the lytic (linear) genomic configuration among a predominantly latent (episomal) population at diagnosis. The episomal populations were of uniform molecular weight at diagnosis and relapse, indicating clonal tumor expansion from a single EBV-infected progenitor. The presence within malignant epithelium of defective virus that can disrupt EBV latency, and perhaps cellular gene regulation, suggests a potential mechanism for EBV reactivation and concurrent malignant progression.

Adolescent↗
PubMed1994

Vowel identification in mixed-speaker silent-center syllables.

Strange [J. Acoust. Soc. Am. 85, 2135-2153 (1989b)] has demonstrated that there is sufficient information in the onsets and offsets of syllables, spoken in sentence context, to provide accurate identification of the vowel in the syllable. Verbrugge and Rakerd [Language Speech 29, 39-57 (1986)] and Andruski and Nearey [J. Acoust. Soc. Am. 91, 390-490 (1992)] have shown that such information is present in citation-form syllables even when the syllables begin with one speaker and end with another. These studies of "hybrid syllables," however, reported relatively high error rates. In a perceptual experiment using /dVd/ syllables spoken in sentence context by a male and a female speaker, relatively low error rates were obtained for both "silent-center" syllables and "hybrid silent-center" syllables. It was concluded that the information specified over syllable onsets and offsets together for identification of vowels is speaker independent and that it was sufficient in most cases to specify the vowel. The acoustic patterns, represented as functions of log (F2/F1) over time, revealed potentially useful dynamic acoustic characteristics of co-articulated vowels.

Adult↗
PubMed1994

Predominance of pilocytic histology in dorsally exophytic brain stem tumors.

We report the magnetic resonance imaging (MRI) and clinico-histologic characterization of dorsally exophytic brain stem gliomas (DEBSGs). Between 1983 and 1991, 12 of 51 patients evaluated for the diagnosis of brain stem glioma were found to have DEBSGs emanating from the pons, pontomedullary junction or medulla. Eleven of the 12 patients had classic juvenile pilocytic astrocytomas. Unlike most other brain stem tumors, these patients were young (median 38 months, range 17-75), had a relatively long duration of symptoms (median 7 months, range 2-24) and displayed signs of increased intracranial pressure with limited cranial nerve paresis, absence of pyramidal tract findings, and near normal brain stem auditory-evoked potentials. MRI characteristically showed sharply demarcated lesions with decreased signal intensity on T1, and increased intensity on T2 sequences. Except for cystic areas, these tumors showed bright, uniform enhancement after gadolinium-DTPA. In all patients, 50-100% of the tumor volume could be resected. Three of 10 patients who received no immediate postoperative treatment eventually demonstrated disease progression, and 2 patients with subtotal resections who were treated with radiation and/or chemotherapy postoperatively remain disease-free for extended periods of time. The only death occurred in the 1 patient treated with chemotherapy who died of secondary leukemia. The overall and progression-free survival of these patients at 2 years is 100 and 67% as compared to 18 and 21%, respectively, for other concomitantly treated nonexophytic brain stem gliomas.2+ the ability to achieve significant degrees of resection.

Astrocytoma↗
PubMed1994

Medulloblastoma in very young children: outcome of definitive craniospinal irradiation following incomplete response to chemotherapy.

PURPOSE: To evaluate survival and neurodevelopmental outcomes following radiation therapy in infants and young children with residual or progressive medulloblastoma after primary chemotherapy. PATIENTS AND METHODS: Thirteen young patients (< or = 36 months old) with medulloblastoma were treated with preirradiation multiagent chemotherapy and maximal surgical resection. Patients were scheduled to receive radiation therapy at the time of documented disease progression or upon completion of chemotherapy with residual disease. All patients underwent neurodevelopmental evaluation at the time of diagnosis, before receiving radiation therapy, and at yearly intervals posttreatment. RESULTS: Two patients completed the scheduled chemotherapy with residual disease and received delayed radiation therapy. The remaining 11 patients had either local or leptomeningeal progression during chemotherapy (median time to progression, 5 months). Six patients had a complete response (CR) to radiation therapy, and three of these children are alive 48 to 104 months postdiagnosis. Of the five patients who had progressive disease (PD) during radiation therapy or residual imaging abnormalities after treatment, only one is alive (with stable enhancing leptomeningeal abnormalities) 48 months postirradiation. Two additional survivors were rendered disease-free by surgical resection before radiation therapy and are without evidence of disease at 91 and 107 months after diagnosis. Thus, six of 13 patients are alive at 48 to 107 months postdiagnosis. Neurodevelopmental scores tended to be below age norms at diagnosis; scores improved during chemotherapy, but then decreased during posttreatment follow-up evaluation. CONCLUSION: Radiation therapy appears to produce long-term disease-free survival in a proportion of very young patients who have progressive or residual medulloblastoma during or after primary chemotherapy. However, neurodevelopmental deficits are frequent among long-term survivors.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Persistent hyperplastic primary vitreous of the eye: imaging findings with pathologic correlation.

Persistent hyperplastic primary vitreous is a rare benign developmental disorder of the globe in which the embryonic hyaloid artery fails to regress normally, resulting in abnormal lenticular development and secondary changes of the retina and globe. This entity often presents a diagnostic challenge as it is the most common intraocular abnormality to be confused with retinoblastoma. Sonography, CT, and MR imaging have been used alone and in combination to diagnose this condition. This essay illustrates the imaging characteristics of persistent hyperplastic primary vitreous in two children with unilateral disease and in one child with bilateral disease as representative cases (Figs. 1-3). Available pathologic correlates also are presented.

Diagnosis, Differential↗
PubMed1994

Abnormal odontogenesis in children treated with radiation and chemotherapy: imaging findings.

Contemporary oncotherapy has improved survival of children with malignant diseases, but chemotherapy and radiotherapy also have deleterious effects. This essay illustrates the effects of chemotherapy and radiotherapy on dentition in children and adolescents. The illustrated abnormalities were seen on panoramic radiographs obtained before, during, and after treatment. Included are examples of hypodontia (partial anodontia), microdontia, altered eruption patterns, and root stunting. Comparison is made with normal dental development (Fig. 1).

Adolescent↗