Furthermore, King Fahd Specialist Hospital is one of the three central hospitals in Tabuk City and receives a referral from the primary healthcare centers and regional hospitals in Tabuk Region. All the records of patients who were diagnosed with cancer during the period from January 2019 to January 2021 were eligible. The study was conducted over three months, from January to April 2023. The records in the Pathology Department were well-organized and easy to access and retrieve the data. A structured checklist was used to collect demographic data. Age, sex, nationality, marital status, residence inside Tabuk, type of cancer, stage, and histopathology were recorded. In addition, the extent and behavior of malignancies were recorded.

Inclusion criteria

All adults who were diagnosed with cancer.

Exclusion criteria

Children with cancer were not included.

Ethical issues

The author strictly adheres to the Helsinki Declaration. All the information was anonymous; no private information was taken. Ethical clearance was obtained from the ethical committee of the University of Tabuk (UT-282-125-2023).

Data analysis

The data were entered into an Excel sheet and presented as percentages and mean± SD. The Statistical Package for Social Sciences (IBM, SPSS, version 20, New York).)

Results and Discussion

There were 354 patients (48% women) with malignancies; their mean age was 52.05±17.71 years, the majority were Saudis (79.4%), 48.3% were married, and 90.97% were from Tabuk City Table 1.

In the present study, the biopsy source was lymph nodes in 18.1% and breast in 14.4%. Colon in 14.1%, and thyroid in 12.1%. Lung tissue constituted 3.9%, and nasopharyngeal, stomach, and mouth biopsy represented 3.7%, 3.7%, and 3.1%, respectively. Table 2 depicts the cancer site in the study group.

In this study, nearly two-thirds (61.3%) were carcinoma in situ, 18.4% showed lymph node metastasis, and 9% distant metastasis (Table 3). Regarding the behavior of cancer, 99.4% were malignant, and 0.6% were paired sites (Table 4).

The commonest histopathological finding was carcinoma (malignant and undifferentiated), followed by adenocarcinoma in 19.8% and papillary thyroid carcinoma in 10.5% (Table 5).

There is an increasing trend of cancer in Saudi Arabia. Breast cancer was the most common cancer in this study, followed by colon cancer; our findings are in a systematic review and meta-analysis published in Saudi Arabia and included thirty-nine studies.^[10] The risk factors were various genetic polymorphism,^[11-13] a lower folate uptake,^[14] and vitamin D deficiency.^[15] The trial conducted by Yousef et al. (2013) found an association between the incidence and invasiveness of breast cancer and low vitamin D levels. However, a single trial with a small sample size cannot conclude a cause and effect. Similar studies from Mexico and Iran ^[16] concluded the association between vitamin D deficiency and breast cancer. In this study, colon cancer constituted 14.1% of all types of cancer and was second most common; the current findings are in line with previous studies conducted in Saudi Arabia ^{[17, 18]} and found colon cancer second cancer after breast cancer. The authors explained their findings by the high rate of polymorphisms. However, Al-Ghafari et al. (2019) explained the high prevalence of breast cancer by vitamin D deficiency.^[19] Aldiab et al. (2017), and Alqahtani et al. (2017) explained the high prevalence of prior ulcerative colitis and family history of Lynch syndrome. Thyroid cancer has increased substantially in the Kingdom of Saudi Arabia over the past three decades (fifteenfold in women and 22 times among men). Importantly, 2056 deaths occurred from thyroid cancer during the same period (the mortality increased three times in women and sixfold in men). In this study, thyroid cancer stands third among cancers in Tabuk City, in line with world trends ^[20] and contradicting previous observations.^[10] The higher prevalence of thyroid cancer might be explained by the increasing detection and diagnosis.^[21] Factors increasing mortality need future studies to reduce the mortality rate. A previous study conducted in Riyadh, Saudi Arabia ^[22] reported that thyroid cancer was the second most common cancer (10%); the current findings supported Hussain and colleagues' findings. However, the current findings were higher than studies conducted in the USA and reported a prevalence of 2.9%.^[23] A study conducted in the southern region of Saudi Arabia ^[24] found that breast, colonic, and liver cancers are the most dominant in line with the current observation.

The geographic and spatial variation in cancer can be explained by radiation exposure,^[25] lifestyles,^[26] and iodine deficiency.^[27] In the present study, the mean age group of the patients was 52.05±17.71 years, with an equal female/male ratio similar to Alshatwi et al. (2012).^[11]

The study limitations

The study limitation was the retrospective nature, and the study was conducted at a single tertiary center.

Conclusion

The commonest malignancies in Tabuk City were breast, colon, and thyroid, respectively; carcinoma in situ was the commonest, followed by lymph node and distant metastasis. The histopathology varied between carcinoma, adenocarcinoma, and papillary carcinoma of the thyroid. Further prospective studies investigating cancer risk factors are needed.

Acknowledgments

None.

Conflict of interest

None.

Financial support

None.

Ethics statement

The records were approached confidentially with strict adherence to the Declaration of Helsinki. No patient identities were taken. The information collected was used only for this research. The ethical approval has been obtained from the ethical committee of the University of Tabuk, Saudi Arabia (ref. number, dated April 30, 2023).