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Biomedical subjects

T E Larsen

Publications and source records attributed to T E Larsen.

At least 19 recordsLinked to original sources
PubMed1990

The inhibiting effect of PABA on photocarcinogenesis.

The efficacy of a 5% solution of para-aminobenzoic acid (PABA) to protect against photocarcinogenesis was tested in 6 groups, each of which contained 30 light pigmented hairless mice. The light source was a Phillips TL 40 W/12, which mainly emits UVB. PABA significantly retarded the tumor induction time (p less than 0.05) and reduced both tumor yield and carcinoma yield (p less than 0.05). The dorsal skin of the mice was removed and weighed. The mean weight of UVR-exposed mice skin protected with PABA did not differ from that of the controls, but in the non-protected UVR-exposed mice the skin samples were significantly heavier (p less than 0.05).

4-Aminobenzoic Acid↗
PubMed1990

Serum carotene concentrations in normal infants and children.

The blood of 444 healthy Canadian children (246 males and 198 females) aged 6 days to 18 years was analyzed to determine the concentration of serum carotene. The serum carotene concentration was very low in the first six months of life. In the first three months of life, breast fed infants had significantly higher serum carotene concentration than infants who were formula fed. Infants 7 to 12 months of age had the highest serum carotene concentration. The serum carotene concentration dropped off after the age of one year and remained low until two years of age. After two years of age, the serum carotene concentration showed a progressive and small rise until the age of six to seven years and then fell until the age of 14 to 18 years. The serum carotene concentration did not appear to vary according to the sex of the child except for infants 7 to 12 months of age. In infants 7 to 12 months of age, girls had a higher serum carotene concentration. The measurement of the serum carotene concentration is a simple screening test for fat malabsorption. Our study provides the normal range of serum carotene concentration for children of various age groups.

Adolescent↗
PubMed1990

Seasonal variations of pigmented naevi. Intercorrelations of clinical and histological variables with special reference to seasonal variation.

During 1984, junctional and compound naevi were registered significantly more often during the summer half-year (May-October) than the total number of naevi, which showed no seasonal variation. A series of 342 of these junctional and compound naevi have been the subject of a blind histological classification. Clinical information was obtained by a questionnaire mailed to the patients. The intercorrelations of 19 histological and 10 clinical variables were studied by chi 2-test. The seasonal variation of these variables was further studied by chi 2-test and by Hewitt's test. Patient's hair colour, eye colour and sex as well as mitoses and localization showed a significant correlation to season of the year. The trends of these findings, compared with the information about tumour duration, indicate a short-term latency effect of UV light on naevi which are excised during the summer half-year.

Adolescent↗
PubMed1979

Scleroderma with massive regional lymphadenopathy.

Scleroderma in a two-year-old boy with gross enlargement of the right inguinal lymph nodes, as an early sign, is reported. Repeated lymph node biopsies revealed non-characteristic reactive changes and hyperplasia, but eventually histological examination of skin and muscle from the right leg were diagnostic. The effect of one year of D-penicillamine therapy is briefly mentioned.

Child, Preschool↗
PubMed1979

A retrospective histological study of 669 cases of primary cutaneous malignant melanoma in clinical stage I. The consequences of a reclassification of the original group of lentigo maligna melanomas.

A selected series of primary malignant melanoma of the skin, clinical stage I, was originally classified according to Clark's system. The consistency of this classification was tested by two Brisbane pathologists who indicated that we had misinterpreted some cases of superficial spreading malignant melanoma as lentigo maligna melanoma. We have therefore reclassified the original group of 86 lentigo maligna melanomas. This resulted in a total series of 37 (5.5%) lentigo maligna melanomas, 301 (45%) superficial spreading malignant melanomas, 194 (29%) nodular malignant melanomas (unchanged) and 137 (20.5%) unclassifiable malignant melanomas. The diagnosis of lentigo maligna melanoma was not made unless the epidermis was atrophic and dermal solar elastosis was present. The new group of lentigo maligna melanomas is dominated by cases on the head among patients over 50 years of age (especially women). This is in better agreement with other studies than our previous findings. The relationship with tumour cell type, pigmentation, mitotic count, atypia, transsectional profile, level of invasion, ulceration, vascular invasion, lymphocyte infiltration and prognosis shown by the new groups of lentigo maligna melanoma and superficial spreading malignant melanoma indicates that the cases by which the diagnosis has been changed are relatively benign. Our previous conclusions are still valid. The lentigo maligna melanoma is still the most benign type and nodular malignant melanoma still the most malignant type of melanoma. The superficial spreading malignant melanoma still represents an intermediate tumour type, although it has deviated in the benign direction.

Adult↗
PubMed1979

A retrospective histological study of 669 cases of primary cutaneous malignant melanoma in clinical stage I. 4. The relation of cross-sectional profile, level of invasion, ulceration and vascular invasion to tumour type and prognosis.

A selected series of 669 primary cutaneous malignant melanomas, stage I, was studied. The series includes 86 lentigo maligna melanomas, 259 superficial spreading malignant melanomas, 194 nodular malignant melanomas and 130 unclassifiable malignant melanomas. The cross-sectional profile, level of invasion, ulceration and vascular invasion were graded. The relation of these features to each other and to tumour type was studied by X2 tests. The prognostic value was also studied. The most common finding was a slightly elevated surface, level III of invasion, no ulceration and no vascular invasion. Most of these tumours were superficial spreading malignant melanomas. A good prognosis was associated with a flat cross-sectional profile, level II of invasion, no ulceration and no vascular invasion. A poor prognosis was associated with marked protrusion of the surface, level IV--V of invasion, ulceration and vascular invasion. Lentigo maligna melanomas tended to be more benign while nodular malignant melanomas tended to be more malignant than the average. A superficial spreading malignant melanoma could vary in either direction. The prognostic value of level of invasion and ulceration was found to be greater than that of tumour type. The prognostic importance of invasion no further than level III is stressed. Level of invasion ought to be reported to the clinician as well as the tumour type.

Blood Vessels↗
PubMed1979

A retrosepctive histological study of 669 cases of primary cutaneous malignant melanoma in clinical stage I. 6. The relation of dermal solar elastosis to sex, age and survival of the patient and to localization, histological type and level of invasion of the tumour.

A selected series of primary malignant melanoma of the skin, clinical stage I, was studied. The series includes 37 lentigo maligna melanomas, 301 superficial spreading malignant melanomas, 194 nodular malignant melanomas and 137 unclassifiable malignant melanomas. Dermal solar elastosis was graded. The most common finding was lack of solar elastosis which together with slight elastosis was mostly found on the trunks of young men and on the legs of young women in cases of superficial spreading malignant melanoma. Marked and moderate elastosis was found almost exclusively on the head, especially in old women with lentigo maligna melanoma. Nodular malignant melanoma was related neither to any special grade of solar elastosis, nor to localization, but showed some relation to the male sex after 50 years of age. The present study does not permit any conclusions to be made about a possible causal relationship between the three types of malignant melanoma and previous sun-exposure, because of lack of clinical information and a control series concerning solar elastosis in the normal population. Level of invasion and prognosis of the patient did not show any covariation with grade of solar elastosis.

Adult↗
PubMed1978

Mucocele of the paranasal sinuses. A retrospective clinical and histological study.

Clinical and radiological findings in 112 patients with muco/pyocele in the paranasal sinuses are presented. The modified Lynch-Howarth operation gave a primary cure rate of 82% which is satisfactory compared with other reports. Histological examination of the mucocele membranes and anamnestic information support the theory that a mucocele develops secondary to obstruction of the sinus outlet.

Adolescent↗
PubMed1978

Transient intestinal lymphangiectasia.

Intestinal lymphangiectasia may be more protean in clinical manifestations and less rare than earlier suspected. A recent report points out that there are two types of the disorder, one congenital and the other acquired and transitory. A case is reported which fulfills the current clinical, laboratory, radiological and histological criteria for the diagnosis of the disease, and represents the first report in Scandinavia of transient intestinal lymphangiectasis with rapid and complete recovery within a few months after initiation of MCT diet.

Child↗
PubMed1978

A retrospective histological study of 669 cases of primary cutaneous malignant melanoma in clinical stage I. I. Histological classification, sex and age of the patients, localization of tumour and prognosis.

A selected series of 669 primary malignant melanomas of the skin, stage I, has been classified according to Clark's system into lentigo maligna melanoma (86), superficial spreading malignant melanoma (259), nodular malignant melanoma (194) and unclassifiable malignant melanoma (130). It was often difficult to distinguish between lentigo maligna melanoma and superficial spreading malignant melanoma, and sometimes also between this last type and nodular melanoma. There seem to be borderline cases between the respective types. The 10-year specific cumulative survival rate (approximately the cure rate) was 98.3% for the lentigo maligna melanomas, 78.6% for nodular malignant melanomas and 76.7% for the unclassifiable group of melanomas. The 5-year observed prognosis ofthe 3 main types is satisfactory compared with other investigations. As the prognosis of the 3 types of cutaneous malignant melanoma differs considerably the use of this classification is recommended. The number of unclassifiable cases is likely to be reduced in the routine work when several sections of each tumour are studied.

Adolescent↗
PubMed1978

The classification of primary cutaneous malignant melanoma. A prospective study of 60 cases using Clark's classification.

A series of 60 primary cutaneous malignant melanomas has been studied by serial block technique. The resulting 492 sections have been classified as junctional naevus with or without atypia and preinvasive or invasive malignant melanoma according to Clark (1967). No sections showed lentigo maligna (melanoma). The overall classification resultedin 49 superficial spreading malignant melanomas, 6 nodular malignant melanomas and 5 unclassifiable malignant melanomas. In 3 cases (5%) there was inconsistency between the classification of the central section and the overall classification of the tumour. Five theoretical growth patterns have been postulated ranging from thatof the pure superficial spreading malignant melanoma completely surrounded by a preinvasive area to the pure nodular malignant melanoma which completely lacks any such area. Borderline cases between these two types certainly seem to exist. Features such as intraepidermal Pagetoid growth of tumour cells, co-existence of a benign melanocytic component and histological changes indicating tumour regression have been discussed. It is recommended that at least 3 tissue blocks should be taken from all malignant melanomas up to 25 mm in diameter and more if the tumour is larger.

Adolescent↗
PubMed1978

A retrospective histological study of 669 cases of primary cutaneous malignant melanoma in clinical stage I. 2. The relation of cell type, pigmentation, atypia and mitotic count to histological type and prognosis.

A selected series of 669 primary malignant melanomas of the skin, stage I, was studied. The series includes 86 lentigo maligna melanomas, 259 superficial spreading malignant melanomas, 194 nodular malignant melanomas and 130 unclassifiable malignant melanomas. The tumour cell type was classified and the tumour cell pigmentation, the cellular atypia and the mitotic count was graded. The relation of these four tumour cell features to each other and to the tumour type was studied by X2tests. The prognostic value of these features in relation to the total series as well as to each tumour type was also examined. The most common features were mixed cellularity, little pigment, moderate atypia and low mitotic count. Most of these tumours were superficial spreading malignant melanomas. A good prognosis was related to spindle-shaped tumour cells, marked pigmentation, slight atypia and few mitoses. A bad prognosis was related to epithelioid tumour cells, little pigment, marked atypia and many mitoses. Variations of lentigo maligna melanoma tended to be more benign while variations of nodular malignant melanoma tended to be more malignant than the average. A superficial spreading malignant melanoma might vary in either direction.

Humans↗
PubMed1978

Remissions of mycosis fungoides induced by nitrogen mustard (HN2). Topical treatment and hydration of tumours and plaques with HN2. Topical desensitization to HN2. A clinical and histopathological controlled study.

In this study 12 patients with mycosis fungoides were treated with whole body topical application of HN2. In addition 4 of these patients had gauzes moistened with the same HN2 solution placed upon plaques and tumours. 4 patients developed in allergic contact dermatitis, and this complication was overcome by percutaneous desensitizing in 3 of them. After starting hydration of plaques and tumours with HN2, the average time to obtain complete clinical remission was shorted from 4.4 to 2.5 months. A little later at the optimal histologic response, there was no or almost no cellular infiltration in 5 cases, while in 6 cases there was only a slight, unspecific, lymphocytic infiltrate in the dermis.

Administration, Topical↗
PubMed1978

A retrospective histological study of 669 cases of primary cutaneous malignant melanoma in clinical stage I. 3. The relation between the tumour-associated lymphocyte infiltration and age and sex, tumour cell type, pigmentation, cellular atypia, mitotic count, depth of invasion, ulceration, tumour type and prognosis.

A selected series of 669 primary malignant melanoma of the skin, stage I, was studied. The series included 86 lentigo maligna melanomas, 259 superficial spreading malignant melanomas, 194 nodular malignant melanomas and 130 unclassifiable malignant melanomas. The adjacent lymphocyte infiltration was graded and its prognostic value and its relation to the sex and age of the patient, tumour cell type, pigmentation, cellular atypia, mitotic count, depth of dermal invasion, tumour type and ulceration was studied. There was no significant relationship between lymphocyte response and sex and age of the patient and the tumour cell type. There was a highly significant relationship between a dense lymphocyte infiltration and superficial tumour invasion as far as the papillary-reticular interface in contrast to the weak response associated with deeper invasion. When only tumours with invasion of the papillary-reticular interface were considered, there was no significant relationship between lymphocyte infiltration and pigmentation, cellular atypia, mitotic count, tumour type and ulceration. At the same level of invasion there was no difference in prognosis in relation to the density of lymphocyte infiltration. Nodular malignant melanomas surrounded by a dense lymphocyte infiltration had a significantly worse prognosis than was associated with a simular lymphocyte response against the two other types of melanoma.

Age Factors↗
PubMed1977

Squamous cell carcinoma appearing in X-ray-treated mycosis fungoides.

Two patients with mycosis fungoides developed a squamous cell carcinoma of the skin on the neck. Upon verification by routine biopsy testing of material taken from a suppurating infiltrate of the neck, both patients were treated intermittently with X-rays. Both had developed the squamous cell carcinoma on a sun-exposed area. Patient 1 had been treated with Grenz-ray irradiation totalling 10 kilovolt (kV) 4400 rad. and Dermopan step IV (50 kV) 5200 rad.; while patient 2 recieved altogether: Grenz-rays 4600 rad., Dermopan step IV 400 rad., and soft X-rays (150 kV) 800 r. The latency period was, respectively, 3 and 10 years.

Carcinoma, Squamous Cell↗
PubMed1977

Reticular erythematous mucinosis syndrome: report of a case.

A 47-year-old man with erythematous, maculopapular rash on the chest and the back. Histology showed perivascular infiltration of lymphocytes, especially around hair follicles, and alcian green positive deposits in the dermis. Some improvement was achieved by treatment with 200 mg oxychloroquine sulphate (Plaquenil, Winthrop) twice daily.

Erythema↗