Biomedical subjects

N B Kumar

Publications and source records attributed to N B Kumar.

At least 37 records · Page 2Linked to original sources

PubMed1987

Evaluation of an emergency cricothyrotomy instrument.

An emergency cricothyrotomy device was placed in 11 anesthetized dogs in order to assess airway damage and problems in placement, ventilation, and design. Posterior airway perforation without esophageal damage occurred in three animals. Submucosal hematomas or cricoid cartilage injury occurred in seven animals. As placement by an untrained operator was surprisingly difficult, prior operator training with this device is recommended. When properly installed, an excellent emergency airway was achieved. Some minor design shortcomings are noted and suggestions for improvement are made.

Airway Obstruction↗

PubMed1987

Quantification of IgG-containing plasma cells as an adjunct to histopathology in distinguishing acute self-limited colitis from active idiopathic inflammatory bowel disease.

ASLC is clinically and endoscopically similar to active idiopathic IBD, especially ulcerative colitis. While several histopathologic criteria have been described which are useful in distinguishing these conditions, the diagnosis can still be difficult. In this study, we review the use of immunofluorescence on formalin-fixed paraffin-embedded biopsies from patients with ASLC. While tissues from active IBD have a striking increase in the number of IgG- and a lesser increase in the IgA- and IgM-containing plasma cells in the lamina propria, tissues from ASLC have normal numbers of IgG-containing cells with only a slight increase in IgA- and IgM-containing cells. The use of immunofluorescence on these tissues can provide quantifiable information which may be a helpful diagnostic adjunct in distinguishing these alternatives if histopathologic evaluation is equivocal.

Colitis↗

PubMed1987

An assessment of pathologic features and treatment modalities in ovarian tumors of low malignant potential.

Sixty-eight patients with epithelial ovarian tumors of low malignant potential treated at the University of Michigan Medical Center were reviewed for clinical and pathologic features related to recurrence or death. The ovarian tumor of low malignant potential represented 12.6% of all ovarian cancers and 22% of all serous or mucinous tumors. Thirty-four patients were stage I (50%), 13 were stage II (19%), 17 were stage III (25%), two patients could not be staged, and two patients developed ovarian tumor of low malignant potential in a residual ovary. The risk of recurrence was significantly related to stage III disease (P = .023), high nuclear atypia (P = .020), and high grade (P = .017); and was unrelated to capsular status, the presence of psammoma bodies, nucleoli, cribriform pattern, stratification, cystadenofibroma, tumor size, or spillage at surgery. Therapy in all stages included observation, chemotherapy, or radiotherapy. There was one recurrence in 47 patients with stages I-II, and 11 recurrences in 17 patients with stage III disease. The ovarian tumor of low malignant potential carries an extremely favorable prognosis in stage I and II regardless of therapy. Radiotherapy appeared to extend disease-free survival in stage III disease, and future randomized studies should consider this treatment modality.

Adult↗

PubMed1986

Prognostic features of vulvar melanoma: a clinicopathologic analysis.

We studied 19 cases of vulvar melanoma to determine significant clinical and histologic prognostic predictors. The average follow-up time was 32 months. Fourteen patients died of melanoma, four patients are alive with no evidence of melanoma, and one patient is alive with residual melanoma. All disease-free survivors had clinical stage I disease and a maximum tumor thickness of 1.3 mm. The average mitotic count in this group was 5.5 per 10 high power fields (HPF) and 50% of the tumors were superficial spreading melanomas. All survivors were treated by radical vulvectomy with bilateral inguinal lymph node dissection. Of the nonsurvivors, four (28.5%) were clinical stage I, five (36%) were clinical stage II, four (28.5%) were clinical stage III, and one (7%) was clinical stage IV. The average tumor thickness for nonsurvivors was 9.5 mm (range 2.6-18 mm) and the average mitotic count was 13.3/10 HPF. Only three (21%) tumors from nonsurvivors were superficial spreading melanomas; the majority were nodular melanomas. The statistically significant prognostic predictors were clinical stage of disease and tumor thickness. Tumor type (i.e., superficial spreading, nodular, or acral lentiginous) correlated with tumor thickness and was indirectly related to prognosis. The mitotic count was also a useful prognostic feature.

Adult↗

PubMed1985

Microinvasive carcinoma of the vagina: a distinct clinical entity?

Six patients with superficially invasive squamous carcinoma of the vagina are described. All had less than 2.5 mm of invasion as measured from the surface, lacked involvement of the lymph-vascular spaces, and arose within a field of carcinoma in situ. Three of the six had previously been treated for carcinoma of the cervix. The patients with microinvasive carcinoma had a median age 10 years younger than that of patients with Stage I carcinoma of the vagina. Treatment of the six patients has been by partial or total vaginectomy. With follow-up of 51 to 172 months, there have been no recurrences. More experience is needed to define microinvasive squamous carcinoma of the vagina and to determine the optimal treatment for these lesions.

Adult↗

PubMed1985

Carcinoma of the vagina. Factors influencing treatment outcome.

A 33-year review from the University of Michigan Medical Center of 86 cases of primary carcinoma of the vagina included 68 squamous carcinomas, 13 adenocarcinomas, and 5 small cell carcinomas. There was a 26% incidence of prior cervical carcinoma and a 21% incidence of prior pelvic radiation therapy. The median interval between the diagnosis of invasive cervical and vaginal carcinoma was 20 years. Survival was strongly correlated with stage. There was no association between survival and involvement of a particular vaginal segment or the amount of vaginal surface area involved with tumor. Irradiation was the most frequently employed primary therapy for vaginal carcinoma. Local control was correlated with the mid-tumor irradiation dose, with predictable control obtained only with doses above 7500 rad. The use of interstitial therapy should facilitate local control without increasing the complication rate.

Adenocarcinoma↗

PubMed1985

Primary sarcoma of the adult vagina: a clinicopathologic study.

Combination chemotherapy has dramatically improved the results of treatment for embryonal rhabdomyosarcoma of the vagina in children, but little attention has been directed toward vaginal sarcomas in adults. This report of 17 cases of primary sarcoma of the adult vagina includes ten leiomyosarcomas, four mixed mesodermal tumors, one undifferentiated sarcoma, one stromal sarcoma, and one neurofibrosarcoma. The leiomyosarcomas, mixed mesodermal tumors, and the stromal sarcoma were morphologically similar to their uterine counterparts. Thirty-five percent of the patients had received pelvic irradiation for carcinoma of the cervix. Three of four patients treated by pelvic exenteration are alive and disease free after 84 to 161 months of observation. All 13 patients who received other forms of primary therapy died of recurrence. The pelvis was the first site of recurrence in all treatment failures and the only site of failure in 50%.

Adenocarcinoma↗

PubMed1985

Prognostic significance of groin lymph node metastases in squamous carcinoma of the vulva.

A retrospective review of the clinical and histologic findings in 48 cases of stages I, II, and III (excluding T3) squamous carcinoma of the vulva with positive groin nodes reveals the prognostic significance of the size and number of the nodal metastases. Other factors such as the morphology of the lymph nodes and the histologic features of the primary neoplasm are not nearly as significant. Patients with only one or two small nodal metastases have an excellent outlook for survival providing that adequate margins can be obtained around the primary tumor and that thorough groin node dissections can be performed. These patients do not appear to need adjuvant radiation or pelvic node dissection. A further finding is that patients with unilateral labial carcinomas do not have metastases to the opposite groin in the absence of ipsilateral groin metastases, although six of 21 patients had metastases to both groins.

Carcinoma, Squamous Cell↗

PubMed1984

The prognostic significance of tumor emboli in lymphatic or vascular spaces of the cervical stroma in Stage IB squamous cell carcinoma of the cervix.

The presence of tumor emboli in lymphatic or vascular spaces within the cervical stroma in squamous cell carcinoma of the cervix has been reported by several authors to be associated with a decrease in 5-year survival. In a 10-year review of 124 radical hysterectomies for Stage IB squamous cell carcinoma of the cervix at the University of Michigan from 1970 to 1980 the presence of tumor emboli in the cervical stroma without other known risk factors did not significantly alter the 3- and 5-year survival. With the potential risks and lack of proved benefit the use of adjuvant radiotherapy or chemotherapy in this setting is not recommended.

Adult↗

PubMed1984

Autopsy findings in patients with uterine sarcoma.

Autopsy findings were reviewed in 22 patients treated for uterine sarcoma at the University of Michigan Hospitals. Included are 11 mixed mesodermal tumors, 6 endometrial stromal sarcomas, and 5 leiomyosarcomas. Only one patient died with disease limited to the pelvis. Forty-five percent of the patients died with disease limited to the pelvis and abdomen. The most common site of the disease above the diaphragm was the lung. Lymph nodes were involved in 59% of our patients. There were no obvious differences in the patterns of spread between the tumor types.

Combined Modality Therapy↗

PubMed1984

Small cell carcinoma of the endometrium in a 23-year-old woman: light microscopic and ultrastructural study.

The case of a 23-year-old woman with a primary small cell carcinoma of the endometrium is reported. The light microscopic features were similar to those of small cell carcinoma of the lung and those of the uterine cervix. Electron microscopy revealed cytoplasmic neurosecretory type granules and indistinct cell junctions, features characteristic of neuroendocrine cells. The neoplasm behaved in a very aggressive manner, similar to that of small cell carcinoma of the lung and quite unlike that of the usual endometrial adenocarcinoma. Small cell carcinomas of the endometrium with neurosecretory type granules may have a worse prognosis than better differentiated endometrial adenocarcinoma with argyrophilic granules and thus may require adjuvant radiotherapy or chemotherapy or both.

Adult↗

PubMed1984

Benign polyps with prostatic-type epithelium of the urethra and the urinary bladder. A suggestion of histogenesis based on histologic and immunohistochemical studies.

The clinicohistologic features of seven urethral and four urinary bladder polyps with prostatic-type epithelium are described. The average age of the patients was 50 years. Seven patients had prior cystoscopies and in none of them was the lesion noted initially. Histologically the lesions were papillary or polypoid and the surface was lined predominantly by prostatic-type epithelium with interspersed transitional epithelial cells or by transitional epithelium with interspersed prostatic-type epithelial cells. The prostatic-type columnar cells contained foamy, faintly eosinophilic cytoplasm, which stained strongly for prostate specific antigen and prostatic acid phosphatase. In all the lesions, there were prostatic acini in the underlying fibrovascular stroma, which was devoid of smooth muscle. The intermingling of prostatic-type cells and transitional epithelium, on the surface of the polyps, the absence of lesions at previous cystoscopies, the coexistence of cystitis cystica glandularis (a metaplastic lesion), and the older age group of our patients suggest that the prostatic-type epithelium in the polyps of urethra and urinary bladder is an acquired lesion, most likely a metaplastic response of transitional epithelium, which embryologically was multipotential.

Acid Phosphatase↗

PubMed1984

Prognostic features of sarcomas and mixed tumors of the endometrium.

A retrospective study of 103 patients with endometrial sarcomas treated at the University of Michigan Hospital includes 47 mixed homologous tumors, 32 mixed heterologous tumors, 21 pure homologous sarcomas (endometrial stromal sarcoma), and three pure heterologous sarcomas (rhabdomyosarcomas). Clinical characteristics appeared similar among the four patient groups. Fourteen percent of the patients had received previous pelvic irradiation. Twenty-nine percent of the patients with a clinical stage I or II tumor had extrauterine disease discovered at surgery. Extent of the tumor at the time of surgery strongly correlated with outcome, and only two patients with extrauterine disease were long-term survivors. Life table survival probability at five years was 58% with surgical stage I, 33% with surgical stage II, 13% with surgical stage III, 0 with surgical stage IV, and 5% in patients referred with recurrence. Risk factors predicting treatment failure were analyzed separately in surgical stages I and II using Cox model analysis. There was no difference in risk for treatment failure between pure endometrial stromal sarcoma, mixed homologous sarcoma, or mixed heterologous sarcoma. The strongest factor correlating with a poor outcome was deep myometrial invasion (P less than .001). An adverse trend was detected in those patients with previous pelvic irradiation, with advancing patient age, and with increasing uterine size, although these differences did not reach statistical significance. Neither the presence of heterologous tumor elements nor cervical involvement were found to be adverse prognostic factors.

Actuarial Analysis↗

PubMed1983

Microinvasive squamous carcinoma of the vulva: search for a definition.

All cases of stage I squamous cell carcinoma of the vulva from the University of Michigan Tumor Registry from 1935 to 1981 were reviewed. Seventeen of 90 (19%) patients had nodal metastases. All had a depth of invasion of more than 2 mm and all exhibited histologic confluence. The risk of nodal metastases varied with depth of invasion, size of lesion, and histologic grade, although the association with grade was not statistically significant. The size of the lesion influenced the incidence of nodal metastases only in that it was associated with the depth of invasion. Lymphovascular invasion was present in only four patients, but three of them had nodal metastases, including one patient with only 3 mm depth of invasion.

Carcinoma, Squamous Cell↗

PubMed1982

Metastases to the uterine corpus from extragenital cancers. A clinicopathologic study of 63 cases.

This report is an analysis of 63 cases of metastatic cancers to the uterine corpus from extragenital neoplasms. The patients' ages ranged from 34-88 years (mean, 59.7 years). Twenty lesions were discovered in surgical specimens and 43 were detected at autopsy. The primary tumors arose in the breast (42.9%), colon (17.5%), stomach (11.1%), pancreas (11.1%), gallbladder (4.8%), lung (4.8%), cutaneous melanoma (3.2%), urinary bladder (3.2%), and thyroid (1.6%). In five (25%) of the surgical cases, uterine metastases were the first indication of the presence of an extragenital primary cancer. Metastases to leiomyomas were found in 13 instances. The myometrium was more often involved than the endometrium, but endometrial curettings contained the metastatic tumor in numerous cases. Metastases to the ovaries were detected in almost two thirds of cases. Although an infrequent event, abnormal uterine bleeding may result from secondary spread to the uterine corpus from an extragenital primary neoplasm.

Adult↗

PubMed1982

The histopathologic spectrum of acute self-limited colitis (acute infectious-type colitis).

Acute self-limited colitis (ASLC) is a self-limiting diarrheal illness which is often caused by known infectious agents (Campylobacter, Salmonella, and Shigella), but many cases are of unknown etiology. This report describes the histopathologic features of acute self-limited colitis as related to its natural history. The extent of inflammation and regeneration varies with the duration of the disease. In the peak activity stage (within 0-4 days of onset of bloody diarrhea) there is mucosal edema, cryptitis, crypt ulcers, and abscesses. At the time of resolution (within 6-9 days of onset of bloody diarrhea), regenerative features become apparent along with residual focal neutrophilic cryptitis. In the latter stages of resolution, along with some regenerative features, occasional crypts with transmigrating lymphocytes may be present. A rectal biopsy is diagnostic only in the early stages of the disease. Later in the course, the rectal biopsy from patients with ASLC may be nondiagnostic or may be confused with Crohn's disease due to the persistence of focal cryptitis. In our experience, the presence of crypt distortion and basal plasmacytosis are the two most useful criteria to differentiate chronic ulcerative colitis from ASLC.

Acute Disease↗

PubMed1980

Megakaryocytes in pleural and peritoneal fluids: prevalence, significance, morphology, and cytohistological correlation.

Over a period of 22 years, 4844 pleural and peritoneal fluids from 3279 patients were examined cytologically. Megakaryocytes were found in the fluids from five patients. The clinical diagnoses in the five patients were agnogenic myeloid metaplasia, chronic myeloid leukaemia, and lymphocytic lymphoma. All of these patients had persistent serous effusions. Megakaryocytes in serous fluids occurred in three forms: (1) a large type with abundant cytoplasm and multilobed nuclei, (2) a smaller type with a high nucleocytoplasmic ratio and unlobed nuclei, and (3) anucleate cytoplasmic masses. Foci of agnogenic myeloid metaplasia found on the serous surfaces at necropsy of two patients contained megakaryocytes similar to those in the corresponding effusions. The clinical course of our patients confirmed that the presence of megakaryocytes in serous fluids signifies an advanced haematopoietic malignancy.

Aged↗

PubMedDate not supplied

The effect of duration of intervention and locus of control on dietary change.

Scientific evidence supports a relationship between diet and the incidence of cancer. This finding has resulted in dietary recommendations that have been disseminated to the public. To reduce actual cancer incidence, these recommendations must lead to dietary changes among the population. We compared two brief dietary interventions with a longer term intervention and found that all three interventions produced significant reductions of calories, fat, fiber intake, and weight. The duration of the intervention did not significantly affect the magnitude of these reductions. We also found that health locus of control did not affect dietary change. Participants who initially were found to have an internal locus of control, or who subsequently internalized their locus of control during the period of observation, did not demonstrate a significant change in their intake of any of the nutrients measured when compared to participants with an external locus of control. Thus, we suggest a brief dietary intervention as a feasible and effective mechanism to produce progressive incremental dietary changes in a large population.

Adult↗