A health watchdog says changes have been made to how people with thyroid problems are assessed, following slack care in the case of a woman who was eventually found to have cancer.
She required extensive surgery and radiotherapy, according to a decision published today by Health and Disability Commissioner Anthony Hill.
The woman had gone to a GP in 2011 about a 2cm lump in her neck. Blood tests were normal and she had an ultrasound scan at Pacific Radiology.
The sonographer - scan operator "Mr B" - did not scan the lymph nodes near the thyroid.
Radiologist "Dr C" thought at the time that the scan suggested goitre, an enlargement of the thyroid gland, but "he now feels that the right lower lobe nodule shows findings that are suspicious, and he should have recommended a biopsy at the time", Hill's report says.
The woman had a number of primary care consultations over the following two years and sought referral to a specialist, which led to scans and biopsies (tissue samples).
The biopsies confirmed papillary thyroid carcinoma in the nodule of the right lobe of the thyroid and also in an adjacent mass.
Pacific and the two Pacific health workers breached of the code of patients' rights, Hill ruled.
The company's protocol did not explicitly refer to the need to assess and/or scan lymph nodes adjacent to the thyroid, Hill said, but it was accepted professional practice to do the wider scan. Mr B's work was "sub-optimal" because he did not follow that accepted professional practice.
"Pacific Radiology Limited was aware of Mr B's practice to adequately fulfil the minimum requirements of an examination, but did not take action to ensure that he extended his examinations, in order to be consistent with accepted practice."
Hill said Pacific had changed its protocols to include the requirement that sonographers assess and/or scan adjacent lymph nodes when scanning the thyroid.
He wants the sonographers' registration authority to ensure a "consistent approach to ultrasound scanning of the thyroid, including the adjacent lymph nodes".
He criticised Dr C's failure to query the lack of imaging of the woman's local lymph nodes - and his failure to interpret the 2011 scan as showing suspicious findings.