PubMed Health⌕ Search

Biomedical subjects

Krishnan K Unni

Publications and source records attributed to Krishnan K Unni.

9 recordsLinked to original sources

Survivorship analysis in patients with periosteal chondrosarcoma.

UNLABELLED: To investigate outcome and identify prognostic factors, we retrospectively reviewed 24 consecutive patients with periosteal chondrosarcomas. There were 17 males and seven females with a mean age of 37.6 years (range, 15-73 years). The femur was involved in 12 patients, the proximal humerus in five, the tibia in two, and the distal fibula, ilium, pubis, metatarsal, and rib in one patient each. The mean greatest dimension of the lesions was 8.1 cm (range, 1.5-27 cm). Based on the histologic pattern, there were 18 Grade 1 tumors and six Grade 2 tumors. All patients were treated surgically. Two patients had intralesional excisions, five patients had marginal excisions, and 17 patients had wide resections. With a mean followup of 17 years (range, 28 months-47 years), seven of 24 patients (29%) had one or more local recurrences. The 5-year local recurrence-free survival was less in patients treated with intralesional or marginal excisions (25%) than for patients treated with wide resections (93%). At the latest followup, six of 24 patients (25%) had died of pulmonary metastases. The overall 5-year metastasis-free survival was 83%. The 5-year metastasis-free survival was less for patients with Grade 2 tumors (50%) than for patients with Grade 1 tumors (94%). LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series no, or historical control group). See the Guidelines for Authors for a complete description of levels of evidence.

Adolescent↗

Periosteal osteosarcoma: long-term outcome and risk of late recurrence.

The long-term outcome of periosteal osteosarcoma is not well defined. We sought to examine the disease-specific survival and risk of late recurrence or dedifferentiation in a cohort of 29 patients with average of 15.8 years followup. Disease-free survival was 83%, with five patients dying of disease at an average of 26 months after presentation. Survival was similar with respect to anatomic location, pathologic grade, and limb-salvage resection. All instances of local recurrence, metastatic disease, and death occurred within 3 years after presentation. There were no instances of dedifferentiation. Long-term disease-free survival is possible after resection of the local recurrence. Limb-salvage therapy seems to offer survival equivalent to amputation, and there does not seem to be a substantial risk of late recurrence, dedifferentiation, or disease progression.

Adolescent↗

Lateral malleolus en bloc resection and ankle reconstruction for malignant tumors.

UNLABELLED: Four children and six adults required en bloc resection of the lateral malleolus for malignant tumors. There were four osteosarcomas, three chondrosarcomas, two Ewing's sarcomas, and one adamantinoma. Surgical margins were wide in seven patients, marginal in two, and intralesional in one. A primary ankle arthrodesis was done in four adults and bracing without any reconstruction was done in four children and two adults. During a mean followup of 14.5 years (range, 3-30 years), there were two local recurrences (two of 10 patients) after a marginal excision and an intralesional excision. One patient had reoperation for a skip osteosarcoma lesion in the proximal fibula. Other complications included chronic osteomyelitis, a lateral talus subluxation and cavovarus deformity, and recurrent ankle instability and degenerative changes of the ankle. At the latest followup, all 10 patients showed no evidence of disease. Five patients who had primary or late ankle arthrodesis had a Musculoskeletal Tumor Society and International Society of Limb Salvage functional score of 28 points (92%), and two adolescents who had postoperative bracing alone had a functional score of 24 points (80%). The three remaining patients had a salvage amputation. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series--no, or historical control group). See the Guidelines for Authors for a complete description of levels of evidence.

Adolescent↗

Intratumoral administration of a 1,2-dimyristyloxypropyl-3- dimethylhydroxyethyl ammonium bromide/dioleoylphosphatidylethanolamine formulation of the human interleukin-2 gene in the treatment of metastatic renal cell carcinoma.

BACKGROUND: Leuvectin (Vical Inc., San Diego, CA) is a gene transfer product in which a plasmid encoding the human interleukin-2 (IL-2) gene is complexed with the cationic lipid 1,2-dimyristyloxypropyl-3-dimethylhydroxyethyl ammonium bromide/dioleoylphosphatidylethanolamine (DMRIE/DOPE). In the current study, the authors investigated the safety and efficacy of in situ vaccination with Leuvectin in patients with metastatic renal cell carcinoma. METHODS: Thirty-one patients with metastatic renal cell carcinoma were treated with intratumorally administered Leuvectin at doses ranging from 0.75 to 4 mg. These patients subsequently were evaluated for response and for treatment-related toxicity. RESULTS: Treatment was well tolerated: no Grade 3 or 4 toxicities were observed in association with the study agent. Documented side effects included Grade 1 pain at the injection site (20%); mild (i.e., Grade 1 or 2) constitutional symptoms, including malaise/myalgia, low-grade fever, and chills (74%); Grade 1 fatigue (19%); Grade 1 or 2 nausea (10%); and Grade 2 allergy (1 occurrence). Two patients experienced partial responses, which endured for 32 months and 6 years, respectively, and 1 patient currently is experiencing a pathologic complete response, which, to date, has persisted for 50 months; thus, the overall response rate was 10%. In addition, 7 patients (23%) experienced disease stabilization for a median of 8 months (range, 4-48 months). The median duration of survival from the start of Leuvectin treatment was 11 months (range, 2-72 months), with a 1-year survival rate of 48% and a 3-year survival rate of 19%. Laboratory analysis of tumor samples revealed the presence of IL-2 plasmid DNA in six of eight patients posttreatment, increased IL-2 expression in tumor cells in four of eight patients posttreatment, and increased tumor infiltration by CD8-positive lymphocytes in five of eight patients posttreatment. CONCLUSIONS: Immunotherapy with intratumorally administered Leuvectin is safe and can lead to durable objective responses in patients with metastatic renal cell carcinoma.

Adult↗

Chondroblastoma of the hands and feet.

OBJECTIVE: To review the imaging findings, age and gender distribution of chondroblastoma of the hands and feet. DESIGN AND PATIENTS: Twenty-five cases of pathologically proven chondroblastoma of the hands and feet were reviewed. Available imaging modalities included radiographs (n=24), CT (n=3), MRI (n=5), and radionuclide bone scintigraphy (n=1). The following imaging features for each case were tabulated: location, presence of sclerotic margin, calcification, expansion, presence of fluid/fluid levels on cross-sectional imaging and surrounding edema on MRI. The images were evaluated for skeletal maturity using closure of the physeal plate in the region as a standard. RESULTS: The average age at time of diagnosis was 23 years (range 7-57 years). Eighty-four percent (n=21) of the patients were skeletally mature. Males (20 of 25) outnumbered females by a ratio of 5:1. The bones of the foot accounted for 22 cases: calcaneus (n=8), talus (n=8), metatarsals (n=3), and the cuboid (n=3). The bones of the hand accounted for three cases: phalanx (n=1), triquetrum (n=1), and a metacarpal (n=1). Radiographically all lesions were osteolytic with identifiable calcification in 54% (13 of 24). Fluid/fluid levels were seen in four of five cases on MRI. Edema on MR images was seen in 40% (2 of 5). The size of the lesions ranged from 2 to 41 cm(2). CONCLUSION: Chondroblastomas of the hands and feet share many of the radiographic characteristics seen in the long bones, but manifest in skeletally mature patients with a higher male to female ratio than in long bone chondroblastoma. Talar and calcaneal lesions were encountered only in males. Chondroblastoma of the wrist and hand appears to be exceptionally rare.

Adolescent↗

Radiographic differentiation of enchondroma from low-grade chondrosarcoma in the fibula.

To evaluate demographic and radiographic features that may differentiate between enchondroma and low-grade chondrosarcoma of the fibula. The radiographs of ninety-three histologically-confirmed cartilaginous tumors of the fibula were retrospectively reviewed along with demographic information as to patient age and gender. Fifty-four enchondromas and thirty-nine low-grade chondrosarcomas were included in the study. Multiple previously-established radiographic features distinguishing enchondroma from chondrosarcoma were evaluated in each fibular tumor in a consensus manner by two experienced, board-certified and fellowship-trained musculoskeletal radiologists. Five radiographic features were shown to statistically favor chondrosarcoma over enchondroma in the fibula. These were soft-tissue mass ( p<0.0001), periosteal reaction ( p=0.008), cortical disruption in the juxta-articular fibula ( p=0.0133), cortical thickening ( p=0.032), and tumor size greater than 4 cm ( p=0.0046). No statistically-significant demographic differences were found between patients with enchondroma and chondrosarcoma of the fibula. When two or more of the identified features of malignancy are identified in the same patient, chondrosarcoma is 2.4 times more likely than in those patients exhibiting none of the features of malignancy. Soft-tissue mass, periosteal reaction, cortical disruption in the juxta-articular fibula, cortical thickening, and tumor size greater than 4 cm indicate chondrosarcoma over enchondroma of the fibula. Radiographs demonstrating more than one of the identified malignant features are more likely to be due to chondrosarcoma than radiographs demonstrating none or only one of the identified features. No unique malignant features of chondrosarcoma in the fibula were observed when compared to previous descriptions of these tumors in the long and short tubular bones of the appendicular skeleton.

Adolescent↗

Dedifferentiation in low-grade mucoepidermoid carcinoma of the parotid gland.

Mucoepidermoid carcinoma (MEC), a common malignant salivary gland neoplasm, is generally divided into low-, intermediate-, and high-grade types according to the histologic features. To our knowledge, the present report describes the first case of dedifferentiation occurring in a low-grade MEC. A 55-year-old man presented with a biphasic neoplasm of the right parotid gland composed of low-grade MEC and dedifferentiated high-grade anaplastic undifferentiated carcinoma. Immunohistochemically, carcinoembryonic antigen expression was restricted to the low-grade MEC portion. The Ki-67-labeling index was higher in the dedifferentiated component than in the low-grade component. On image cytometric analysis, the low-grade MEC was diploid, whereas the dedifferentiated carcinoma was aneuploid. Although the patient was alive 10 years after the initial diagnosis, the tumor has recurred twice, at 3 months and 7 months after the initial resection. It is important to recognize that dedifferentiation can occur in a low-grade MEC, similar to other low-grade salivary gland carcinomas.

Aneuploidy↗