Seasonal variations in the presentation and growth of thyroid cancer

Abstract

Summary Seasonal variation has been described in the presentation and growth of several malignant tumours, including cancers of the breast, uterus, uterine cervix, urinary bladder, liver, lymphatic system and skin, although the mechanisms are not known. We herein describe a circannual rhythm for thyroid cancer (total = 2627), with significantly more cases presenting during the late autumn and winter. In a subset of these cases (127 papillary carcinomas), significant seasonal variations with highest values in autumn-winter were found for tumour diameter and proliferation indicators (S-and G2M-phase fractions). These results indicate the likelihood of a seasonal factor (or factors) of importance for the regulation and modification of tumour cell proliferation. When further clarified, this might be of relevance for the planning of diagnostic and therapeutic strategies.Keywords: thyroid cancer; season; tumour diameter; proliferation; %S-phase-%G2M-phase Biological rhythms, especially circadian (24 h) and circannual (12 months), have been found in a wide range of physiological parameters and normal tissues (Aschoff, 1981; Shifrine et al, 1982;Halberg et al, 1983;Lerum et al, 1988;Sothem et al, 1995). Regarding seasonal variations, higher incidence of female breast cancer has been reported for the spring and summer (Cohen et al, 1983;Mason et al, 1985), and circannual contrasts have also been found for other tumours (Newell et al, 1985;Swerdlow, 1985; Hermida and Ayala, 1996). As for the thyroid, some studies have reported seasonal variations in endocrine parameters, with variables such as T3, T4 and thyroid-stimulating hormone (TSH) being higher in the autumn or winter (Halberg et al, 1981;Nicolau et al, 1987;Haus et al, 1988). As seasonal variations might be of potential interest for the detection and management of thyroid carcinomas, we wanted to review this group of tumours, most of which are slowly growing and have a good prognosis. MATERIALS AND METHODS PatientsDuring the period 1970-85, 2627 patients with thyroid cancer were reported to the Cancer Registry of Norway. Of these, 10% (n = 263) were surgically treated at the Department of Surgery, Haukeland University Hospital, in the period 1971-85. There were no major differences in the distribution of sex, age and histological types between our hospital cases and cases in the population-based Cancer Registry (Akslen and Myking, 1992 subtyping of malignant tumours according to the 1988 WHO criteria, 127 of these cases were found to represent papillary thyroid carcinomas with a diameter greater than 10 mm (microcarcinomas < 10 mm were excluded). These 127 cases were included for further studies of seasonal variations with reference to time (month) of diagnosis, largest diameter of the primary tumour and proliferation indicators (S-phase and G2M-phase fractions). Most of these patients (93%) were treated with total or near-total thyroidectomy. Regarding time of diagnosis, the date of initial histological/cytological diagnosis was used for both the registry (n = 26...

Circannual variation of efficacy outcomes in patients with newly diagnosed metastatic colorectal cancer and treated with first-line chemotherapy

“…Finally, it has been shown a circannual variation in tumor cell proliferation in non-Hodgkin's lymphomas (Smaaland R et al, 1993) and in thyroid tumors (Akslen LA & Sothern RB, 1998), with acrophases in winter for both studies. Consequently, we may further hypothesize that chemotherapy is more active in wintertime as tumor cells are more proliferating.…”

Effect of seasonal variation on the clinical course of chronic hepatitis B

“…[11][12][13][14][15][16] Such seasonality has been found not only in animals 16,19,33,34 but also in normal humans 18,20,35,36 and associated with some diseases. [5][6][7][8]17,37,38 These previous studies have suggested that seasonal variation of the immune function might also affect the clinical course of chronic liver diseases.…”

“…Any factors that may affect any of these can affect the clinical course of chronic hepatitis B. 3 Seasonal variation has been documented in the exacerbation and attributable mortality of a number of illnesses, [4][5][6] including some liver diseases. 7,8 Whether similar trends exist in chronic hepatitis B is not definitively known.…”

Global breast cancer seasonality

“…Cancer incidence, in general, and breast cancer incidence, in particular, are not randomly distributed throughout the year [1][2][3][4][5][6][7][8][9][10][11]. Abundant epidemiologic literature suggests that human breast cancer is diagnosed more often during spring, both in the Northern and Southern Hemispheres [1,3,4,8,[11][12][13][14][15][16][17].…”