Prevalence and Partern of Early Adverse Reactions in Cancer

The major challenge in the management of cancer patients who are receiving chemotherapy regimens is the manifestation of adverse drug reactions which may be very unpleasant. The objective of this study was to determine the prevalence and pattern of early adverse reactions in cancer patients who are receiving chemotherapy at Ocean Road Cancer Institute. This was a descriptive cross-sectional hospital-based study on patients who were on chemotherapy, either alone or in combination with radiation and/ or surgery. SPSS for descriptive purposes was used to analyze the data. A total of 80 patients were recruited for the study, 64 (80%) inpatients and 16 (20%) outpatients. Seventy-six (95%) out the 80 patients developed adverse reactions. The early manifestation of adverse drug reactions which occurred within 3 days of starting chemotherapy were: fatigue in 66 (82.5%), nausea in 58 (72.5%), loss of appetite in 58 (72.5%) and mouth sores in 28 (35%) of the patients. Those after 2-3 weeks included hair loss in 39 (48.8%) and lower abdominal pain in 52 (65%) of the patients, and 50 (62.5%) of the patients developed anemia. Most of the patients on chemotherapy for cancer developed adverse reactions, which are variable in type and severity. The early detection of these ADRs helped to modify the drug dosage or the drug regimen.


Introduction
Cancer is a global problem accounting for almost 13% of all deaths worldwide. By 2020 it is estimated that there will be 17 million of new cancer cases every year, 60% of whom will be in developing countries where management of cancer patients is still a major challenge. Adverse reactions (ADRs) constitute a major clinical problem in terms of human suffering and increases healthcare costs [1]. The World Health Organization (WHO) defines an ADR as "any response to a drug which is noxious, unintended and occurs at doses used in man for prophylaxis, diagnosis or therapy" [2]. Chemotherapy is employed as part of a multimodal approach to treatment of many tumuors. The dosage, regime and method of administration of some anticancer drugs greatly affect their efficacy and toxicity [3]. The commonly used anticancer drugs at Ocean Road Cancer Institute (ORCI) in Tanzania are alkylating agents, cytotoxic antibiotics, antimetabolites, vinca alkaloids and several other anti-neoplastic drugs [4]. Chemotherapy is used for curative intent in cancer to prolong life or to palliate symptoms. These cytotoxic drugs work by impairing mitosis of fast dividing cells, causing damage to DNA and inhibition of cellular machinery involved in cell division [5]. They affect both cancer and healthy cells (i.e. those of bone marrow, digestive tract and hair follicles), thus leading to undesirable effects.
It has been estimated that about one-third of cancer patients on chemotherapy develop adverse reactions, the exact incidence of adverse reactions is not known [6]. Today, an increasingly important issue in oncology is to ensure the quality of life, (QoL) in cancer patients [7]. In 2012, ORCI Tanzania provided care for 5,500 new cancer patients and also provides over 10,000 follow-up

Material and Methods
This study was conducted at ORCI in 2014 and reviewed on 2019. The study population included patients who were on chemotherapy either alone or in combination with radiotherapy and/ or surgery, inpatients and outpatients. Data collection was done by using a structured questionnaire and analysis was done by SPSS for descriptive statistics

Results
A total of 80 patients on treatment for cancer were recruited for the study at ORCI, which is the only cancer treatment hospital in Tanzania Table 1

Treatment of Side Effects and Outcome
Thirty (40%) of the patients on chemotherapy were given injection emeset (ondesartan) as antiemetic, and all of them did not report any further vomiting. Twenty-two (27.5%) of the patients on chemotherapy were given metoclopramide and did not report anorexia anymore. Patients who had previous history or were likely to develop abnormal respiratory symptoms were given Prednisolone to prevent occurrence of adverse effects. IV dexamethasone injection was given to all patients who developed allergic reactions after chemotherapy, and this gave positive results.
Other patients were given leucovorin to prevent harmful effect of Methotrexate (MTX).

Discussion
The type and severity of adverse reactions in cancer patients who are receiving chemotherapy developed depending on the type of the drugs, the dosage, and how the drugs were given. Fatigue which was reported in 82.5%) of the patients affects mental, physical and emotional wellbeing of the patients and was caused by anaemia resulting from bone marrow suppression by chemotherapy drugs. When the effect of the drug is diminished this condition gradually resolved. These findings are similar to those reported elsewhere [8]. Nausea was reported by 72.5% and vomiting by 60% of the patients respectively. A similar study reported that only 20% of patients experienced nausea before any one chemothera-py cycle, and that up to 30% reported this anticipatory, learned, or psychological nausea by the fourth chemotherapy cycle; repeated exposure to chemotherapy was associated with an increased risk of developing nausea and vomiting [9]. Loss of appetite was reported by 72% of the patients and was associated by weight loss. A similar study reported that 80% of the patients with advanced cancers had nausea and weight loss [10]. Sores developed due to reactions of chemotherapy regimens on cells overlying the gastrointestinal tract. In a similar study, approximately 51% of the patients reported to have developed mouth sores. The severity the mouth sores was correlated with fatigue [11]. Hair loss is the most prominent ADR after 6 weeks cancer chemotherapy. However, re-growth occurs within 3 months after cessation of chemotherapy and hair growth rate returns to baseline value. Tamoxifen did not affect hair growth [12].

Conclusions
Most of the patients on chemotherapy for cancer develop adverse reaction, which are variable in type and severity. The early detection of these ADRs helps to modify the doses or the drug regimen to minimize hazardous effects. The provision of prophylaxis against some of the ADRs reduces the occurrence of adverse reactions and allows completion of the required chemotherapeutic regimen.