Krecke K N, Gisvold J J
Department of Diagnostic Radiology, Mayo Clinic, Rochester, MN 55905.
AJR Am J Roentgenol. 1993 Nov;161(5):957-60. doi: 10.2214/ajr.161.5.8273634.
Invasive lobular carcinoma of the breast is a distinct malignant neoplasm consisting of small cells that tend to infiltrate in thin strands that are often only one cell in width. The objectives of this study were to determine if these tumors are more frequently overlooked on mammograms than are other types of invasive carcinoma and to evaluate the specific mammographic and pathologic findings of this disease at the time of diagnosis.
From 1983 through 1991, invasive, purely lobular carcinoma of the breast was diagnosed in 184 women who had screen-film mammography and biopsy at our institution. We examined the initial mammographic reports to determine the principal abnormal mammographic findings that supported or prompted biopsy and to distinguish abnormalities that were overlooked in breasts with false-negative mammographic findings. All mammograms were retrospectively examined for benign or suspicious microcalcification in the vicinity of the neoplasm and for breast parenchymal patterns. Surgical pathology reports were also reviewed.
The rate of false-negative findings on initial interpretations of mammograms was 19%. Forty-six percent of the mammograms with false-negative initial interpretation showed no evidence of malignant tumor in retrospect. Ten percent of the neoplasms showed suspicious calcification on mammograms, and 1% of patients had biopsy primarily because of worrisome calcification. Invasive lobular carcinoma tends to produce masses that are of relatively low radiographic opacity, similar to normal fibroglandular breast tissue. Forty-four percent of patients had metastases to axillary lymph nodes at the time of diagnosis. One patient had bilateral invasive lobular carcinoma.
Our results show that the false-negative rate for the diagnosis of invasive lobular carcinoma is higher than that for other invasive cancers. The reasons for this difference appear to be the low rate of suspicious calcification found with invasive lobular carcinoma and its tendency to be of low opacity. We also found a lower rate of bilateral invasive lobular carcinoma than has been generally reported. Metastases to lymph nodes were common at the time of diagnosis.
乳腺浸润性小叶癌是一种独特的恶性肿瘤，由小细胞组成，这些小细胞倾向于呈细条索状浸润，且通常仅有一个细胞的宽度。本研究的目的是确定这些肿瘤在乳房X线照片上是否比其他类型的浸润性癌更常被漏诊，并评估该疾病在诊断时的具体乳房X线照片和病理表现。
1983年至1991年期间，在我们机构对184名接受乳腺钼靶筛查和活检的女性诊断出乳腺浸润性纯小叶癌。我们检查了最初的乳房X线照片报告，以确定支持或促使活检的主要异常乳房X线照片表现，并区分在乳房X线照片结果为假阴性的乳房中被漏诊的异常情况。对所有乳房X线照片进行回顾性检查，以查找肿瘤附近的良性或可疑微钙化以及乳腺实质形态。还查阅了手术病理报告。
乳房X线照片初始解读时的假阴性率为19%。初始解读为假阴性的乳房X线照片中，46%的病例回顾时未发现恶性肿瘤迹象。10%的肿瘤在乳房X线照片上显示可疑钙化，1%的患者主要因令人担忧的钙化而接受活检。浸润性小叶癌倾向于产生在影像学上相对低密度的肿块，类似于正常的纤维腺性乳腺组织。44%的患者在诊断时出现腋窝淋巴结转移。1例患者患有双侧浸润性小叶癌。
我们的结果表明，浸润性小叶癌的诊断假阴性率高于其他浸润性癌症。这种差异的原因似乎是浸润性小叶癌发现可疑钙化的比率较低及其低密度的倾向。我们还发现双侧浸润性小叶癌的发生率低于一般报道。诊断时淋巴结转移很常见。
